Power control for a network of access points

Power control for access point networks

Claim priority

This patent application claims that the jointly owned U.S. Provisional Patent Application No. 61/386,278 filed on September 24, 2010 and assigned agency case No. 102987P1, and filed on September 28, 2010 and was filed The rights and priority of US Provisional Patent Application No. 61/387,433 with agency case No. 102910P1 are assigned, and the disclosures of each of these two applications are incorporated herein by reference.

Generally speaking, this case is about wireless communication, and it is specific and not exclusive. This case is about improving communication performance.

A wireless communication network can be deployed on a defined geographic area to provide users in the geographic area with various types of services (for example, voice, data, multimedia services, etc.). In a typical implementation, access points (for example, corresponding to different cell service areas) are spread over the network to provide access to access terminals (for example, cellular phones) operating in the geographic area served by the network. Provide wireless connection.

With the rapid growth in demand for high-speed and multimedia data services, the realization of an efficient and robust communication system with enhanced performance is facing challenges. In order to supplement general network access points (for example, macro access points), small coverage access points (for example, with 20 dBm or less transmit power) can be deployed to provide more robust coverage for the access terminal. For example, a small coverage access point installed in a users home or a corporate environment (for example, a commercial building) can provide voice and access terminals for access terminals that support cellular radio communications (for example, CDMA, WCDMA, UMTS, LTE, etc.) High-speed data service.

Conventionally, for example, a small coverage access point may be called a femtocell service area, a femto access point, a home node B, a home eNodeB, or an access point base station. Usually, such a small coverage access point is connected to the Internet or mobile service provider's network via a DSL router or cable modem. For convenience, in the following discussion, the small coverage access point may be referred to as a femtocell service area or a femto access point.

In practice, it may be necessary to provide sufficient femtocell service area radio frequency (RF) coverage and limit interference to other access points (for example, the nearby macrocell service area) for users in the femtocell service area. A compromise is made between the interference of the users of these other access points. For example, for a femtocell service area deployed indoors, it may be desirable to restrict outdoor leakage (otherwise the outdoor leakage may interfere with the uplink and/or downlink communications of nearby access points) while simultaneously operating in the entire building Provide good indoor RF coverage inside.

Interference is caused in many ways. Due to the scarcity of spectrum resources, the femtocell service area often shares the frequency channel used by the macrocell service area, or is deployed on adjacent channels with a limited guard band. In any of these cases, the femtocell service area and the macrocell service area may interfere with each other on these channels.

Another cause of interference is beacon transmission. The macro cell service area usually operates on multiple frequencies. In order to attract users of the macro cell service area to their service channels, the femtocell service area sends out beacons (for example, including pilot frequency, paging, and synchronization channel) on the frequency of the macro cell service area. If there is no effective delivery support between the macro cell service area and the femto cell service area, these beacons will interfere with the macro network. This interference may affect the voice dialing quality of users receiving effective services on the frequency of the macro cell service area, and in some cases, cause the call to be interrupted.

In view of this, it is desirable to calibrate the transmit power of the femtocell service area service channel and the femtocell service area beacon channel to provide adequate coverage while reducing interference to the macro network. In some aspects, the desired power level depends on the indoor area and propagation environment, as well as the general macro network conditions. For example, the traditional interference mitigation technology can use the network monitoring module (NLM) to detect the channel quality of the surrounding macro cell service area, and calibrate the femto cell service area transmit power based on the detected channel quality. Generally, NLM includes receiver components that are configured to acquire forward link signals transmitted by nearby access points. However, these methods are usually based on overly simple assumptions related to interference changes in the coverage area and the macro cell service area, and therefore cannot provide the desired level of coverage. Therefore, there is a need for improved RF coverage control for wireless networks.

The following provides an overview of several exemplary aspects of the disclosure of this case. This summary is provided for the convenience of readers, and is not a comprehensive limit to the scope of the content disclosed in this case. For convenience, the term certain aspects may be used in this case to represent a single aspect or multiple aspects of the content disclosed in this case.

The disclosure in this case involves controlling the transmit power of the femtocell service area network in some aspects. In a typical implementation, the femtocell service area is deployed in an enterprise environment (e.g., in a building) or in a residence.

The disclosure of this case involves a power calibration scheme in some aspects. The power calibration scheme is based on the macro cell service area signals observed at different points in and around the coverage area, and is based on the mutual position of the femtocell service area ( For example, the power level of the femtocell service area is adjusted based on the femtocell service area signals observed at these points. In this way, the power calibration scheme promotes a good balance between providing a desired level of coverage and mitigating interference to nearby macro cell service areas and femto cell service areas. Such a power calibration scheme can be used to control the transmit power of the femtocell service area service channel (hereinafter referred to as the femtocell service area forward link (FL)) and/or the femtocell service area beacon channel transmit power.

The disclosure of this case involved a multi-stage calibration procedure in some aspects. The multi-stage calibration procedure includes two or more of the following: an initialization stage, a power adjustment stage, and a power optimization stage.

In some aspects, during the initialization phase, the power level of the femtocell service area is set by using a network monitoring program. Initially, each femto cell service area belonging to the femto cell service area network (for example, a group or cluster) listens to the macro cell service area signals, and determines the maximum transmission power based on the signals. In an attempt to provide similar coverage areas for these femtocell service areas, each femtocell service area may be assigned substantially the same transmit power level (for example, the same or within a defined delta). In some cases, the allocated transmit power level corresponds to the highest maximum power level determined by any femto cell service area in the femto network during the network monitoring procedure. Correspondingly, in some aspects, the power control scheme includes: receiving transmission power values determined by a plurality of femtocell service areas based on monitoring macro cell service area signals; The pico cell service area determines at least one transmission power value; and at least one femto cell service area in the femto cell service areas is configured to use the determined at least one transmission power value.

In some aspects, during the power adjustment phase, the transmit power of each femtocell service area is determined during a walk-based test procedure in which each femtocell service area moves from The measurement report is received through a specific access terminal (e.g., mobile device) in the coverage area of the femtocell service area (e.g., a craftsman with a cellular phone walks through a building). For example, the measurement reports include indications of received signal strength or signal quality of signals received from the femtocell service area and any nearby macrocell service areas observed by the access terminal at various locations. Correspondingly, in some aspects, the power control scheme includes: sending at least one measurement report request to a designated access terminal; receiving the requested measurement report at the femtocell service area, wherein the measurement report Be associated with a plurality of locations of the designated access terminal; and control the transmit power of the femtocell service area based on the received measurement report, wherein the transmit power is controlled to be in one or more of the locations The location satisfies at least one criterion (for example, a signal-to-noise ratio (SNR) criterion, a handover criterion, a macro cell service area protection criterion, a pilot frequency signal quality criterion, an adjacent channel protection criterion, etc.).

In some aspects, the transmit power of each femtocell service area is adjusted based on the received measurement report to cause each measurement report location in the femtocell service area to receive the highest signal quality of the femtocell service area Where specified criteria (for example, SNR criteria or handover criteria) are met. In some cases, the femtocell service area will filter the received measurement reports to remove any reports received from the femtocell service area that did not cause the highest reception signal quality of the femtocell service area. Correspondingly, in some aspects, the power control scheme includes: receiving a plurality of measurement reports in the first femtocell service area; filtering the measurement reports to eliminate the identification of another femtocell service area as a Any measurement report associated with the received signal quality of the first femtocell service area with higher received signal quality; and controlling the transmit power of the first femtocell service area based on the filtered measurement report.

In some aspects, during the power optimization phase, the reconfiguration of the femtocell service area is triggered based on information obtained as a result of an initial or subsequent training walk-based calibration procedure performed for the femtocell service area (For example, changing the location of the femtocell service area or changing the number of femtocell service areas). For example, in determining: 1) the power difference between the femtocell service areas is too large; 2) too many reports indicate high path loss to the femtocell service area; 3) the femtocell service area operates at maximum power; or 4 ) After the coverage hole exists, an instruction to reconfigure the service area of the femto cell can be generated. Correspondingly, in some aspects, the power control scheme includes: receiving information obtained as a result of a training walk calibration procedure performed for a plurality of femtocell service areas; identifying reconfiguration trigger conditions based on the received information; and As a result of recognizing the reconfiguration trigger condition, an instruction to reconfigure the femtocell service area is generated.

The power calibration scheme can be adopted in a non-centralized (e.g., decentralized) deployment or in a centralized deployment. Taking decentralized deployment as an example, each femto cell service area in the femto cell service area network can obtain measurement reports, and can be independent of the power calibration of other femto cell service areas in the network (for example, , With little coordination with other femtocell service areas or no coordination with other femtocell service areas) to calibrate its transmit power. Taking centralized deployment as an example, an entity (for example, a designated femto cell service area in a femto cell service area, or a network entity such as a base station controller (BSC), etc.) acquires a network femto cell The measurement report obtained by the service area, and the transmit power of the femtocell service area is calibrated accordingly.

The following describes the various aspects of the disclosure of this case. It is obvious that the teachings herein can be implemented in a variety of forms, and any specific structure, function, or both disclosed herein are only representative. Based on the teachings in this article, those skilled in the art should understand that the aspects disclosed herein can be implemented independently of any other aspects, and two or more of these aspects can be combined in various ways. For example, a device can be implemented or a method can be implemented using any number of aspects set forth herein. In addition, using other structures, functions, or structures and functions other than one or more aspects set forth herein, or structures and functions different from one or more aspects set forth herein, can realize such a device or achieve this method. In addition, an aspect may include at least one element of the requested item.

Figure 1 illustrates several nodes of an exemplary communication system 100 (e.g., part of a communication network). For the purpose of illustration, various aspects of the disclosure of this case will be described in the context of one or more access terminals, access points, and network entities that communicate with each other. However, it should be recognized that the teachings of this case can be applied to other types of devices or other similar devices mentioned using other terms. For example, in various implementations, an access point can be called or implemented as a base station, Node B, eNodeB, femto cell service area, home Node B, home eNodeB, etc., and an access terminal can be called or implemented as a base station, Node B, eNodeB, etc. User equipment (UEs), mobile stations, etc.

The access point in the system 100 provides access to one or more services (for example, network connection) for one or more wireless terminals (for example, the access terminal 102), and the wireless terminals can be installed in the system 100. In the coverage area of the system, or roaming in the entire coverage area of the system 100. For example, at various points in time, the access terminal 102 may be connected to the access point 104, the access point 106, the access point 108, the access point 110, or an access point in the system 100 (not shown). Each of these access points can communicate with one or more network entities (represented by network entity 112 for convenience) to facilitate wide area network connections.

The network entity may take various forms such as one or more radio network entities and/or core network entities. Therefore, in various implementations, a network entity can represent functions such as at least one of the following: network management (for example, via operation, operation, management, and configuration entities), dialing control, communication period management, mobility management, Gateway function, interconnection function, or some other appropriate network function. In some aspects, mobility management involves: tracking the current location of an access terminal through the use of tracking areas, location areas, routing areas, or some other appropriate technology; controlling the paging of the access terminal; and providing for the access terminal Access control. In addition, two or more of the network entities may be co-located, and/or two or more of the network entities may be distributed in the entire network.

The power control scheme taught in this case is used to control the transmit power of the access points 104-108. In a typical implementation, the access points 104-108 are femtocell service areas.

At least one of the entities in FIG. 1 includes functions for power calibration coordination 114 based on network listening, power calibration 116 based on training walking, and power optimization 118. In order to reduce the complexity of FIG. 1, this function is only illustrated for the access point 104 (for example, the designated cluster head of the femtocell service area cluster). In practice, at least a part of this function (for example, performing network monitoring measurements and receiving measurement reports from the access terminal 102) is performed in each of the access points 104-108. The rest of the function (for example, calculating the transmit power value based on the information collected by the access points 104-108) can be implemented by the access points 104-108 in a decentralized manner, or by such as those in the access points 104-108 A single entity such as a designated access point (for example, a designated cluster head of a femtocell service area cluster) or a network entity. For example, in some implementations, this function is partly implemented in the network entity 112 (for example, a BSC network entity deployed by a network service provider), and partly in the access points 104-108. However, in other implementations, this function can be fully implemented in each of the access points 104-108 in a distributed manner.

For illustrative purposes, this function will be described in the context of a femtocell service area coverage planning procedure using training walks. For example, the procedure includes: determining the number and layout of femto cell service areas to be deployed; determining the initial value of the femto cell service area transmission power that will be used during the training walk; calibrating the femto cell service area emission based on the training walk Power; and perform transmit power optimization. In this case, the determination of the transmit power value can be referred to as supervised mobile station auxiliary range tuning (SMART).

Once the femtocell service area is deployed, the power calibration coordination 114 based on network monitoring determines the initial transmit power to be used by the femtocell service area based on the macrocell service area signal. For example, each femto cell service area is based on the access point FL signal (eg, macro cell service area signal and/or femto cell service area signal) received at the femto cell service area via NLM, using the network Channel monitoring power calibration (NLPC) to determine the initial transmit power value. Subsequently, each femtocell service area sends its calculated transmit power value to the power calibration coordination 114. Subsequently, the power calibration coordination 114 determines the transmission power that each femtocell service area will use during the calibration procedure based on the training walk, and sends corresponding transmission power information to each femtocell service area. Subsequently, the training walk is started. When the access terminal 102 moves along the training walking path 120, the access terminal 102 sends a measurement report to the femtocell service area. Subsequently, the information from the measurement reports is sent to the training walk-based power calibration 116, where the training walk-based power calibration 116 determines the transmit power to be used in the femtocell service area based on the measurement reports. Subsequently, the power optimization 118 is used to determine whether to reconfigure the femtocell service area based on the information determined by the training walk-based power calibration 116 (for example, during the initial or subsequent training walk).

Now, in conjunction with the flowchart of FIG. 2, an exemplary operation that can be used to provide SMART-based femtocell service area coverage planning for building deployment will be described in more detail. For convenience, the operations of FIG. 2 (or any other operations discussed or taught in this case) may be described as being performed by specific components (for example, the components of FIG. 1 or 8). However, it should be recognized that these operations may also be performed by other types of components, or may be performed by using a different number of components. It should also be realized that in a given implementation, one or more of the operations described in this case may not be used.

As represented by block 202, the number of femtocell service areas to be deployed is determined, and the layout of these femtocell service areas is determined. For example, an artisan can select the number and layout of femtocell service areas based on the area and shape of the area to be covered (for example, a house or a corporate building), the material of the structure, and the RF scattering environment. It is generally expected that once a user enters a building, the femtocell service area will serve the user. In this way, a more consistent level of service can be provided (for example, by avoiding call interruptions in the macro cell service area deep into the building), and in some cases, additional services can be provided ( For example, higher bandwidth services). Correspondingly, the typical design goal is that the overall coverage of the femtocell service area covers the entire interior of the building.

At this stage of the process, one or more guidelines can be applied. One guiding principle is that the femtocell service area should be placed as evenly as possible (for example, throughout the enterprise). This action facilitates ensuring that the coverage of each femtocell service area is similar and symmetrical. This will also help avoid forward link/reverse link (FL/RL) imbalance and load imbalance. Another guiding principle is to ensure that each femtocell service area does not have a direct line of sight to the outside of the building (for example, directly through a window). This will help limit the leakage of power from the femtocell service area to the outside of the building. Another guiding principle is to ensure that each femtocell service area is not too far away from any edge and/or corner of the building. This will help prevent the need to cover these locations with very high femtocell service area power settings.

The number of femtocell service areas deployed depends in part on the forward link coverage provided by each femtocell service area. For example, in some implementations, each femtocell service area may have an actual maximum transmit power limit of 15 dBm. In some aspects, coverage can be specified by the femtocell service area FL or femtocell service area beacons. For example, in a dedicated deployment (femto cell service area and macro cell service area are on different frequencies), at the macro cell service area website, the femto cell service area FL coverage can be 90-95 in this case dB, and the beacon coverage of the femtocell service area can be 70-75 dB. At the edge of the macro cell service area for dedicated deployment, the femto cell service area FL coverage can be 110-115 dB in this case, and the femto cell service area beacon coverage can be 95-100 dB. In the same channel deployment (femto cell service area and macro cell service area are on the same frequency), at the macro cell service area website, the femto cell service area FL coverage can be 80 dB in this case. At the edge of the macro cell service area deployed for the same channel, the femto cell service area FL coverage can be 105 dB in this case. In a large enterprise deployment (for example, an office building with walled offices), the guideline for femtocell service area coverage can be, for example, on the order of 7000 square feet.

FIG. 3 illustrates an example of deployment in which four femtocell service areas 302, 304, 306, and 308 are deployed in building B in a simplified manner. It can be seen here that the femtocell service areas 302, 304, 306, and 308 are evenly spaced to a certain extent to have similar coverage areas. These femtocell service areas provide sufficient corner coverage and are not located in the external In direct line of sight (e.g., femtocell service areas 302, 304, 306, and 308 are located in internal rooms).

As represented by block 204 in FIG. 2, once the femtocell service area is deployed, the SMART program 204 is initiated. This includes the transmit power initialization operation, the power adjustment operation assisted by the artisan, and the optimization trigger operation (if applicable).

As represented by block 206, a transmit power initialization operation is performed. In a typical embodiment, all femtocell service areas use NLPC to calibrate their initial power-up values. For example, each femto cell service area can monitor signals from the macro cell service area and/or other femto cell service areas, and calculate its power value (for example, the maximum power value) based on the received signal. Subsequently, the transmission power (for example, the maximum transmission power) of each femto cell service area can be determined based on all the values calculated for different femto cell service areas.

Generally, it is expected that all femtocell service areas use the same or similar transmit power at this point. In some aspects, the goal here is to initialize all femtocell service areas to a similar power level, where the power level is high enough to collect measurement reports from the entire expected coverage area. If the above initialization has been completed, all femtocell service areas will have similar coverage areas during the training walk power adjustment procedure. Therefore, each femtocell service area will try to set its final power level to cover roughly the same area. In this way, all femtocell service areas can obtain substantially equal coverage areas.

As mentioned above, the transmit power that each femtocell service area will use during the training walk can be determined in a centralized manner (for example, by a single entity) or a distributed manner. In the former case, each femtocell service area uses the NLPC program to determine the transmit power value and reports the value to the entity. Based on the received values, the entity calculates the transmit power value to be used by the femtocell service area. In the latter case, each femtocell service area reports the power value calculated by its NLPC to each of the other femtocell service areas. Therefore, a given femtocell service area is based on the value received by the femtocell service area to calculate the transmit power value it will use during the training walk.

In some embodiments, the maximum value among all reported values is calculated, and all femtocell service areas are initialized to the same value. For example, in a centralized embodiment, a single entity calculates the maximum value and sends it to the femtocell service area. In a decentralized embodiment, each femtocell service area calculates the maximum value for itself. In this way, it can be ensured that all femtocell service areas (even those femtocell service areas that are severely interfered by the macrocell service area) can provide adequate coverage.

In some embodiments, in this step, restrictions are imposed on how far the transmit power value initially calculated for a given femtocell service area (for example, a value based on NLPC) can be changed. In this way, the interference to the macro network can be limited to a certain degree. However, in this case, the coverage area of different femtocell service areas may vary slightly.

Generally, the maximum available power (eg, based on hardware constraints) is not selected as the maximum transmit power during the calibration phase. In this way, the impact on the macro channel can be reduced to some extent.

As indicated by the block 208 of FIG. 2, once all the femtocell service areas have initialized their transmit power, the power adjustment assisted by the artisan is performed. Here, all femtocell service areas adjust their power based on the macro environment and the existence of other femtocell service areas around the femtocell service areas. To this end, effective dialing (for example, voice or data connection) is initiated on the channel of the femtocell service area, and training walks are implemented. Preferably, the walking path will fully span the desired coverage area of all femtocell service areas. For example, the training walk can be implemented by mobile phone users or craftsmen (for example, IT craftsmen, Internet service provider craftsmen, etc.).

Although it is feasible to collect measurement reports from users in the femtocell service area to calibrate the transmit power level, this solution has several disadvantages. For example, a user in a femtocell service area may initiate a voice call and walk out of the desired coverage area. Therefore, the femtocell service area that attempts to adapt its coverage will likely expand its coverage area. Therefore, the femtocell service area will eventually transmit at the maximum allowable transmit power (for example, 20 dBm), and cause interference to the macrocell service area network. As another example, the user density or traffic in the femtocell service area may be tilted, resulting in coverage holes in the coverage area. Correspondingly, according to the teachings of this case, it is generally preferable to use a properly defined training path (for example, assisted by a skilled person) to calibrate the transmit power of the femtocell service area.

FIG. 3 illustrates an example of the training walking path represented by the dashed line 310 in a simplified manner. Typically, the path traverses a significant portion of the coverage area of the four femtocell service areas 302, 304, 306, and 308.

During the training walk, the femtocell service area requests the effective action station to measure and report the signal quality of the femtocell service area and the macrocell service area. This gives an indication of the path loss at different points and the observed interference to the serving femtocell service area. All femtocell service areas use this information to adjust their transmit power in an attempt to achieve the best transmit power level. Several examples of algorithms used to calculate the transmit power are described below. During this phase, beacons may or may not be sent depending on the technology (for example, for CDMA 1xRTT, beacons may not be needed; while for CDMA 1xEV-DO, beacons will usually be sent). This procedure can be repeated for further power tuning.

As represented by block 210, after the transmit power calibration operation, an optimization trigger can be used to try to further optimize the femtocell service area location and transmit power value. For example, the optimization may be based on one or more of the following: absolute transmit power level, femtocell service interval transmit power difference, and coverage area served by each femtocell service area.

As represented by blocks 212 and 214, if the optimization criterion is met (for example, no optimization trigger occurs), the deployment is complete and the femtocell service area will use the transmit power value calculated during the transmit power calibration operation . On the contrary, if the optimization criterion is met at block 212 (for example, at least one optimization trigger occurs), an instruction can be issued to notify the skilled person that the number and/or location of femtocell service areas need to be changed. In this case, once the femtocell service area is reconfigured as shown in block 216, the SMART procedure 204 is executed again for the new configuration. The above process is repeated as needed until a satisfactory deployment is obtained.

By using the coverage planning solution taught in this case, several problems associated with multi-femtocell service area deployment (for example, enterprise deployment) can be alleviated. For example, such problems include serious FL/RL imbalance, negative impact on the macro cell service area RL, and negative impact on the macro cell service area FL.

The signal strength of the macro cell service area at different locations in a large building may be due to the distance between the macro cell service area and a given location (for example, a location near a window compared to a location in the middle of the building) and the building The structure changes by a large amount (for example, 20-30 dB). In addition, the power calibration based on the network monitoring scheme alone may cause a large transmit power difference between adjacent femtocell service areas located near the location of the macrocell service area website. This may lead to serious FL/RL imbalances. Here, the user can be served by a stronger but farther femtocell service area on the DL, so that the user will transmit with a relatively higher power on the UL and transmit at a weaker but closer femtocell. The cell service area caused significant disturbance.

In some aspects, the coverage planning taught in this case can be used to alleviate this imbalance. For example, it may be decided to deploy more femtocell service areas, where each of the femtocell service areas will have a smaller coverage area. This configuration will help limit the difference in transmit power in the system.

The impact of femtocell service area users on the RL of the macrocell service area depends on the difference in path loss between users to the macrocell service area and the femtocell service area, and the noise coefficient of the femtocell service area (for example, its Usually higher than the macro cell service area) and the increase in thermal noise (RoT) at the femto cell service area (for example, it may be high due to effective nearby macro cell service area users). If the coverage area of the femtocell service area is large, the users of the femtocell service area at the coverage edge of the femtocell service area will transmit with relatively high power. This, combined with the small path loss difference that may occur at the edge of the femtocell service area, may cause RL interference at the nearby macrocell service area.

The coverage planning taught in this case can also be used to mitigate this interference. By deploying more femtocell service areas with smaller coverage areas, the possibility of femtocell service area users transmitting at the edge of the femtocell service area with high power can be reduced.

Generally, wireless networks do not support delivery from the macro cell service area to the femto cell service area. Therefore, if the femtocell service area has a large coverage area (e.g., to ensure coverage is provided in the corner of a building), there may be significant femtocell service area power leakage outside the building (e.g., via windows). If the femtocell service area has closed access, this kind of leakage may interfere with the users of the effective macrocell service area near the building. In addition, even with open access to the femtocell service area, in some implementations, it is still desirable to control the coverage of the femtocell service area in the building to avoid extra heavy load for users passing by the macrocell service area. Select and deliver to the femtocell service area, or avoid interruption of the call if effective delivery is not supported.

The coverage planning taught in this case can also be used to mitigate this interference. By deploying more femtocell service areas with smaller coverage areas, the possibility of leakage can be reduced. In addition, hierarchical beacons or opportunistic femtocell service area beacons can be used to mitigate interference associated with beacon transmissions in femtocell service areas in buildings. In addition, the coverage planning taught in this case may be relatively easy to implement, and does not require RF measurement activities involving detailed planning or the use of complex equipment. On the contrary, based on the information obtained with the tiny assistance of skilled persons (or other appropriate personnel), a distributed or centralized architecture (for example, via self-calibration) can be used to automatically adapt the transmit power of the femtocell service area to the RF environment.

In consideration of the foregoing, an exemplary operation performed to control the transmission power of a plurality of femtocell service areas will be described with reference to the flowcharts of FIGS. 4-7.

FIG. 4 illustrates an exemplary operation for initializing the transmission power of each femtocell service area in the femtocell service area network. According to a specific implementation, this will include setting the femtocell service area DL transmission power and optionally the femtocell service area beacon transmission power. As represented by block 402, initialization begins after the femtocell service area is deployed.

As represented by block 404, each femtocell service area determines the transmit power based on the monitoring of access point signals (eg, signals from the macrocell service area and/or signals from other femtocell service areas) value. For example, each femtocell service area can perform an NLPC operation based on the received macrocell service area signal and calculate the maximum transmit power of the femtocell service area.

The transmit power value can be calculated based on one or more of the various criteria. In some implementations, the maximum transmit power value is selected to provide sufficient power to obtain valid reports from all areas in the desired coverage area. In some implementations, the maximum transmit power value is selected to limit the impact on users of the macro cell service area during training walks. In some implementations, the maximum transmit power value is selected to provide equal power to the femtocell service area to minimize FL/RL imbalance.

The transmit power value can be calculated based on various received signal information. In some implementations, one or more of the total received power on the channel (eg, Io) and the received pilot frequency energy on the channel (eg, Ecp) may be used to calculate the transmit power. Note that this quantity is measured by the NLM of the femtocell service area. In some implementations, the transmit power is set to meet a specified signal-to-noise ratio (SNR) (e.g., as specified by the defined path loss) at the edge of the femtocell service area coverage. In this case, the transmit power can be calculated based on the measured Io (which is caused by the macro cell service area), the defined path loss, and the target SNR.

In some implementations, the femtocell service area transmit power is selected to meet the coverage condition, for example, in the coverage condition, at the edge of the coverage area, the pilot frequency quality of the femtocell service area (for example, such as UMTS system) CPICH in <i>E</i>_<i>c</i><i>/Io</i>The quality of the shared pilot frequency channel) is designated as better than the defined threshold. In some cases (for example, for UMTS), the threshold corresponds to the SIB 11 message broadcast in the macro cell service area<i>Q</i>_{<i>qualmin, femto</i>}parameter. In addition, in order to limit interference to the macro cell service area network, at the edge of the femto cell service area coverage, the femto cell service area is allowed to transmit as much as the macro cell service area.<i>Io</i>Increase a certain fixed amount. The minimum of the two criteria is selected as the transmit power of the femtocell service area. These procedures allow the femtocell service area transmit power to be adjusted based on the location in the macrocell service area network. For example, compared with the measured location where the received signal strength (for example, RSSI) of the macro cell service area is relatively strong, in the location where the measured received signal strength of the macro cell service area is weak, the transmit power is usually reduced by Set it lower.

In some implementations, the femtocell service area transmit power is selected to meet the coverage conditions and adjacent channel protection conditions. Here, one adjacent channel protection condition corresponds to the same wireless network service provider associated with the femto cell service area being calibrated, and the other adjacent channel protection condition corresponds to the femto cell being calibrated The service providers associated with the service area are different wireless network service providers.

As represented by blocks 406 and 408, each femtocell service area sends its calculated transmit power value to at least one coordinating entity that performs the transmit power control operations of blocks 408-412. According to specific implementations, these transmit power control operations can be performed at various types of entities in the system.

In some implementations, each femtocell service area receives the transmit power value of all other femtocell service areas and bases it on the received transmit power value (for example, by selecting the maximum of all these values) Decide its transmit power. In this case, each femtocell service area includes a coordinating entity that performs the operations of blocks 406-410.

In some implementations, an entity receives the transmit power values of all femtocell service areas, and determines the transmit power to be used based on the received transmit power values (for example, by selecting the maximum of all these values), And send the determined transmit power value to these femtocell service areas. In this case, the centralized entity includes a coordinating entity that performs the operations of blocks 406-410. For example, the entity may be one of the femtocell service areas, a network entity (e.g., BSC), or some other type of entity.

As represented by block 410, the coordination entity determines at least one transmission power value for at least one of the femtocell service areas based on the received transmission power value. In the case that each femtocell service area includes a coordinating entity, a given femtocell service area determines its own transmit power. In the case of a centralized coordination entity, the entity determines the transmit power for each femtocell service area.

As mentioned above, in some cases, the same transmit power value is selected for all femtocell service areas. For example, the maximum value can be selected from all received transmit power values, and all femtocell service areas use this value.

Also as mentioned above, in some cases, the transmit power value selected for a given femtocell service area can be restricted in some way. For example, the maximum value of all received transmission power values can be selected initially. However, the power will be limited so that the power will not increase to a value higher than the initial value calculated by the femtocell service area (for example, the transmission power value based on NLPC) greater than the specified upper limit. In this way, a limit can be imposed on the amount of interference caused to the macro network during the training walk operation.

As represented by block 412, the coordination entity configures at least one femtocell service area to use the transmit power value determined at block 410. In the case that each femtocell service area includes a coordinating entity, a given femtocell service area sets its transmit power based on the value determined at block 410. In the case of a centralized coordination entity, the entity sends the determined value to the femtocell service area. Here, if a single value is calculated at block 410, the value is sent to all femtocell service areas. In contrast, if different values are calculated for different femtocell service areas at block 410, the appropriate value is sent to each femtocell service area. Note that if the entity is a femtocell service area among the femtocell service areas, then the femtocell service area will set its transmit power based on the corresponding value determined by it for itself, and then set the appropriate value Send to other femtocell service areas.

Figure 5 illustrates an exemplary training walk-based transmit power calibration operation for a femtocell service area network. As represented by block 502, after the femtocell service area has set its initial transmit power, initialization begins.

Here, the handover parameter can be set to a value different from the value used during normal operation. For example, in some implementations, the femtocell service area serving the user sets its handover lag parameter (for example, "Hyst") to a value of 0dB, and (for example, via a message that enables hard handover) The indication of the changed value is sent to the access terminal used by the artisan. In some implementations (for example, UMTS femtocell service area), the femtocell service area serving the user has the handover lag parameter minus the cell service area area offset (CIO) set to 0 dB value, and (for example, via a message enabling handover) to send an indication of the value change to the access terminal used by the artisan. In any of these cases, once the access terminal receives a stronger signal from another femtocell service area in the femtocell service area, the access terminal will hand over to the other femtocell service area. A femtocell service area (for example, where the handover operation uses the handover parameters, and the handover operation is currently served by the femtocell service area based on the measurement report received from the access terminal by the serving femtocell service area To control). This is contrary to the normal operation mode, in which in the normal operation mode, the measured signal strength of the other femtocell service area is higher than the measured signal strength of the current femtocell service area by a certain margin (that is, by The non-zero handover lag parameter defines the margin), the handover will occur. By controlling the hysteresis parameter in this way, the access terminal will send its measurement report to the nearest femtocell service area. Therefore, each femtocell service area will more easily collect all measurement reports for the coverage area that the femtocell service area will likely eventually cover.

Therefore, in some aspects, the handover operation at the femtocell service area may include: defining the first handover lag value used for the handover decision during the training walk calibration procedure; and defining the first handover lag value used to complete the training walk calibration procedure A second handover lag value for subsequent handover decisions (eg, during normal, non-initialization operations), where the second handover lag value is different from (eg, higher than) the first handover lag value. Here, the first handover lag value can be defined as such that during the training walk calibration procedure, the access terminal sends each measurement report to the femto cell associated with the strongest received signal value in the measurement report Service area. For example, in some cases, the first handover lag value (for example, "Hyst" or "Hyst-CIO") is approximately zero.

As the artisan establishes an effective call (for example, voice or data) with one of the femtocell service areas, the training walk begins. For example, this may include: a craftsman (for example, by activating a user input device) launching a specific application on the access terminal and/or on the femtocell service area. Therefore, the designated access terminal is recognized as being used to perform training walking operations. Without leaving the coverage area (for example, to avoid generating an unnecessary large coverage area), the skilled person carries the access terminal through a route that preferably fully encompasses the defined coverage area.

As represented by block 504, the femtocell service area currently serving the access terminal sends at least one request for a measurement report to the designated access terminal. The request can be initiated at the femtocell service area or some other entity (for example, when soft handover is supported, the entity that controls the delivery of the soft handover signal will initiate the request and send the request through the femtocell service area The request is sent to the access terminal). In some implementations, the femtocell service area sends a single message that requests the access terminal to send periodic measurement report messages. In some implementations, the femtocell service area repeatedly sends messages, and each of these messages requests the access terminal to send periodic measurement report messages. In addition, the request may specify that the measurement should be performed on the same frequency and/or on at least one other frequency (e.g., adjacent channel). In this way, the femtocell service area transmit power can be calibrated for the same frequency and/or the at least one other frequency. In addition, for implementations supporting multiple wireless technologies (for example, 1xRTT, 1xEV-DO, UMTS, etc.), information from measurement reports based on one wireless technology can be used to control the transmit power for different wireless technologies.

As represented by block 506, the entity that controls the power calibration of the femtocell service area (eg, femtocell service area, network entity, etc.) receives the requested measurement report from the access terminal. As the access terminal moves along the training path, different measurement reports will be associated with different locations of the access terminal in the coverage area.

The type of information provided by each measurement report depends on the wireless technology used by the system. For example, in a 1xRTT system, pilot frequency strength measurement messages (PSMMs) and candidate frequency search report messages (CFRs) can provide Ecp/Io and Io information for femtocell service area frequencies and beacon frequencies. Based on this information (and the known transmit power of the femtocell service area), the path loss from the femtocell service area to the location where a given measurement value is obtained can be calculated. As another example, in a 1xEV-DO system, route update messages (RUMs) can provide Ecp/Io information for femtocell service area frequencies and beacon frequencies. As another example, in the UMTS system, measurement report messages (MRMs) can provide CPICH RSCP and Io information for femtocell service area frequencies and beacon frequencies.

As represented by block 508, the power calibration entity optionally filters the received measurement reports. For example, in the case that the femtocell service area receives measurement reports from other access terminals during the training walk operation, the femtocell service area may (e.g., be based on the access included in the report that provides the report). The identifier of the terminal) to filter out these other measurement reports.

As another example, the femtocell service area can remove any measurement reports that are not from the expected coverage area. In this way, a given femtocell service area can be prevented from trying to cover an unnecessary large coverage area. For example, because when higher received signal strengths from different femtocell service areas are observed at the access terminal, the access terminal handover may not occur immediately, so the current serving femtocell service area can receive List the measurement reports of some other femtocell service area with higher received signal strength. However, it is not necessary for current service access points to try to cover these locations, because these locations will be covered by the other femtocell service area.

Correspondingly, in this case, the femtocell service area can filter the received measurement report to remove any received signal that identifies another femtocell service area as being different from the current service femtocell service area. A measurement report associated with the higher quality of the received signal. For example, the serving femtocell service area may only retain measurement reports of their locations where the serving femtocell service area is reported to provide the highest received signal strength.

As represented by block 510, the power calibration entity controls the transmit power of the femtocell service area (for example, sets the maximum transmit power value) based on the received (if applicable, filtered) measurement report. Here, the transmission power is controlled to satisfy at least one specified criterion at one or more of the locations where the measurement report is made. The following provides some examples of these criteria and ways to control the transmit power based on these criteria. For illustrative purposes, in these examples, it is assumed that the femtocell service area calculates its own transmit power.

1xRTT example:

In the 1xRTT dedicated channel implementation, the beacon power on the macro cell service area frequency can be set to ensure that each position in a set of locations in the desired coverage area (for example, in the femto cell service area from which Most points or all points where the measurement report is received) provide adequate beacon coverage. For example, for each location, the femtocell service area is calculated based on the path loss to the location, the strength of the strongest macrocell service area guide frequency observed at the location (for example, Ecp), and the defined hysteresis threshold to calculate the guarantee The transmit power required to meet the target coverage (for example, the ratio of the pilot frequency power of the beacon to the total power (for example, Ecp/Io), etc.) at this location. In other words, for each location, by ensuring that the pilot frequency power of the beacon at that location is greater than the pilot frequency power of the macro cell service area at that location plus the hysteresis value, the calculation of the beacon discovery (idle delivery) is performed. The required power.

In some implementations, outliers are not considered. For example, it can be determined in advance that only 80% of the locations will be covered. Subsequently, the transmit power of the femtocell service area beacon is selected to be a transmit power that ensures beacon coverage at all locations of interest (for example, to ensure beacon exploration at 80% of reporting points). In this way, the femtocell service area will not select an excessively high transmit power level, and if the femtocell service area is allowed to provide beacon coverage for each location from which the measurement report is received, the femtocell service area will not The pico cell service area may choose an excessively high transmit power level.

As mentioned above, a layered beacon approach is adopted in some implementations. For example, a high-power beacon may be transmitted at certain times (for example, 5% of the time), and a low-power beacon may be transmitted during the remaining time. In this case, the transmit power value can be determined for the high-power beacon and the low-power beacon. For example, the transmission power of a high-power beacon can be selected to ensure the transmission power of beacon exploration at 80% of the location, and the transmission power of a low-power beacon can be selected to ensure the transmission power of beacon exploration at 50% of the location .

In the implementation of the 1xRTT dedicated channel, the femtocell service area FL power on the femtocell service area frequency can be set based on the SNR constraint and the macrocell service area protection constraint. That is, calculate the first transmit power that satisfies the SNR constraint (for example, to ensure good coverage at all points of interest), and calculate the second transmit power that satisfies the protection constraints of the macro cell service area (for example, to limit all points of interest) The impact on the users of the adjacent channel macro cell service area). Subsequently, the minimum value or weighted combination (e.g., average) of these constraints is selected to be used for the femtocell service area FL transmit power.

For SNR constraint calculation, for each location corresponding to the measurement report, the femtocell service area is based on the path loss to that location and the total macrocell service area interference observed at that location (for example, Io), To determine the transmit power required to ensure that the target coverage (e.g., SNR such as the ratio of pilot frequency energy to noise plus interference (e.g., Ecp/Nt)) is satisfied at that location. In other words, for each location, a decision is made to provide the power required to provide a specified Ecp/Nt (for example, -7 dB). Here, the path loss information and total macro cell service area interference information are obtained from the measurement report. Usually outsiders are not considered. Therefore, the first transmit power value for the femtocell service area FL is selected as the transmit power that ensures FL coverage at all locations of interest (for example, the power required to cover 95% of the locations).

For the macro cell service area protection constraint calculation, the femto cell service area determines the maximum allowable transmit power that will prevent excessive interference on the frequency of the adjacent macro cell service area. For example, for each location corresponding to the measurement report, the femtocell service area calculates the FL signal of the femtocell service area at that location based on the path loss to the location and the adjacent channel interference ratio (ACIR) The interference is at least a maximum transmission power with a safety margin lower than the signal strength (for example, Io) of the macro cell service area at the location. In other words, for each location, it is decided to limit the influence on the signal of the adjacent channel macro cell service area to a maximum allowable transmit power that does not exceed a defined value (for example, 1.78 dB). Usually outsiders are not considered. Therefore, the second transmit power value of the femtocell service area FL is selected as the transmit power required to ensure sufficient protection at all locations of interest (for example, the power required to protect 50% (for example, a radius of &gt;10 meters)). ).

As mentioned above, subsequently, the final transmission power for the femtocell service area FL is selected as the minimum of the first transmission power value and the second transmission power value or a weighted combination of the two.

In the 1xRTT same-channel implementation, the beacon power on the macro cell service area frequency can be set based on the same formula used for the dedicated channel implementation. However, in this case, the upper limit of the beacon power can be set based on the calculated femtocell service area FL transmit power for the same channel implementation. For example, the power of the femtocell service area beacon can always be lower than the femtocell service area FL power, so that users who are guided by the femtocell service area beacon to the femtocell service area frequency will observe that it is strong enough to cause Femto cell service area FL signal for reselection of femto cell service area.

In the implementation of 1xRTT on the same channel, the femtocell service area signal provides coverage to users and triggers the macrocell service area user to reselect to the femtocell service area. In some aspects, the FL transmit power of the femtocell service area is set to provide sufficient coverage while being reserved to prevent leakage. The femtocell service area FL power on the femtocell service area frequency may be based on SNR constraints and idle handover (e.g., distribution) constraints. That is, the first transmission power that satisfies the SNR constraint is calculated, and the second transmission power that satisfies the idle handover constraint is calculated. Then, the maximum value (or weighted combination) of these constraints is selected to be used for the transmit power of the femtocell service area FL.

For SNR constraint calculations, for each measurement report location, the femtocell service area determines whether to ensure the The transmit power required to meet the target coverage (for example, SNR such as Ecp/Nt) at this location. Therefore, at this stage of the process, a first set of transmit power values corresponding to each location is provided.

For handover constraint calculations, for each measurement report location, the femtocell service area decides to ensure that the access terminal served by the femtocell service area will not be handed over to the transmit power required by the macro network at that location . Therefore, for each location, the femtocell service area decides to ensure that the femtocell service area pilot frequency strength at that point is higher than the signal strength of the best macrocell service area at that location based on the path loss to that location ( For example, Ecp) is higher than the transmit power required to at least define a threshold (e.g., hysteresis value). At this stage of the process, a second set of transmit power values corresponding to each location is provided.

Next, select the maximum transmit power for each location. That is, for each location, the highest transmission power is selected based on the corresponding values in the first group and the second group. Afterwards, outsiders are usually not considered. Therefore, the final transmit power value of the femtocell service area FL is selected as the transmit power that ensures FL coverage at all locations of interest (for example, the power required to cover 95% of the locations).

Examples of 1xEV-DO:

For 1xEV-DO implementation, operations similar to those described above can be used.

For the same channel 1xEV-DO implementation, the femtocell service area FL power on the femtocell service area frequency can be set based on the SNR constraint and the handover (for example, handover) constraint. In this case, since Io information is usually not available in the 1xEV-DO scenario, the SNR constraint and the macro cell service area protection constraint algorithm are based on the Ecp/Io from all macro cell service areas and are based on Ecp/Io of the beacon signal observed at each location. As mentioned above, outsiders (for example, the 95th percentile) are usually not considered, and the maximum value of the first transmission power calculated to satisfy the SNR constraint and the second transmission power calculated to satisfy the handover constraint is selected as The final FL transmit power of the femtocell service area. In addition, the calculated transmission power value may include (for example, as shown in FIG. 4, relative to the transmission power value set after initialization) an incremental value.

For the same channel 1xEV-DO implementation, the femtocell service area beacon power on the adjacent macrocell service area frequency can be set relative to the 1xEV-DO femtocell service area FL transmit power discussed above. The calculation is also based on the Ecp/Io of the best macro cell service area on the femtocell service area frequency, and the best macro cell service area on the adjacent macro cell service area frequency observed at that location Ecp/Io and the defined fading margin.

For the dedicated channel 1xEV-DO implementation, the femtocell service area FL power on the femtocell service area frequency can be set based on the SNR constraint and the macrocell service area protection constraint. In this case, different algorithms can be used according to whether the adjacent channel interference is higher than the threshold level (for example, the location is near the macro cell service area website). In addition, since Io information may not be available in the 1xEV-DO scenario, the SNR constraint and macro cell service area protection constraint algorithm is based on Ecp/Io from all macro cell service areas, and is based on observations at each location Ecp/Io of the received beacon signal. As mentioned above, outsiders (for example, the 95th percentile) are usually not considered, and the first transmission power calculated to satisfy the SNR constraint and the second transmission power calculated to satisfy the protection constraint of the macro cell service area are selected. The minimum value of is used as the final femtocell service area FL transmit power.

For the dedicated channel 1xEV-DO implementation, the femtocell service area beacon power on the adjacent macro cell service area frequency can be set to facilitate handover (for example, idle mobile station handover). For example, for each measurement report location, the femtocell service area can set the beacon transmission power to ensure that the strength of the beacon is higher than the strength of the strongest macrocell service area by a hysteresis margin. The calculation is based on the Ecp/Io from all the macro cell service areas, and is based on the Ecp/Io of the beacon signal observed at that location and the defined hysteresis value. At this point, outsiders (for example, the 80th percentile) are usually not considered.

UMTS example:

In UMTS, the measurement report message (MRM) contains the CPICH of the primary scrambling codes (PSCs) specified in the measurement control message (MCM) requesting MRM <i>RSCP</i>And CPICH <i>Ec/Io</i>. Femtocell service areas use these MRMs to extract the path loss (PL) to locations covered by artisans walking and the macrocell service areas at these locations<i>Io</i>. Therefore, the femtocell service area (or other power control entity) can obtain an estimate of the required coverage and the RF conditions of adjacent channels, and fine-tune the femtocell service area transmit power accordingly.

FIG. 8 illustrates exemplary power calibration operations that can be performed for each femtocell service area, and the power calibration operations start at block 802. Generally, these operations can be used for various types of transmit power calibration procedures. For example, such a scheme can be used for a calibration procedure based on training walking, a power calibration based on network monitoring (for example, as described in Figure 4 above), or for other types of calibration operations.

As represented by block 804, a decision is made regarding the first transmit power level that satisfies the first frequency for the femtocell service area associated with the first wireless network service provider. Coverage criteria for the wireless communication performed. For each location associated with a different MRM, the femtocell service area is calculated based on the path loss to the location and the RSSI (for example, Io) of the macrocell service area observed at the location to ensure that it is at that location The transmit power required to meet the target coverage (for example, SNR such as CPICH Ecp/Io). In some implementations, outsiders are not considered. For example, it can be pre-determined to provide coverage only for a certain percentage of locations. Therefore, the first transmit power level is selected as the transmit power that ensures coverage at all locations of interest.

As represented by block 806, a decision is made regarding the second transmit power level, the second transmit power level satisfies corresponding to the adjacent channel wireless communication of the second wireless network service provider (other service provider) The first interference criterion. In some implementations, the criterion is based on a comparison of the signal power value (e.g., CPICH Ec) on the adjacent channel with the total received power value (e.g., Io, excluding the femtocell service area). Based on this comparison, the maximum transmit power value can be calculated according to the defined equation.

As represented by block 808, a decision is made regarding the third transmit power level, which meets the requirements of the adjacent channel wireless communication with respect to the first wireless network service provider (the same service provider) The second interference criterion. In some implementations, the criterion is based on the comparison of signal power values (e.g., CPICH RSCP) on adjacent channels with a threshold value. Based on this comparison, the maximum transmit power value can be calculated according to the defined equation.

As represented by block 810, the minimum of the first transmission power level, the second transmission power level, and the third transmission power level is selected. As represented by block 812, the transmit power of the femtocell service area is controlled based on the selected minimum transmit power level. In this way, the selected transmit power level provides the best possible coverage while still meeting the desired adjacent channel interference target.

The above operations are performed at each femtocell service area in the femtocell service area network. When the access terminal moves from the coverage of one femtocell service area to the coverage of another femtocell service area, the other femtocell service area will start to communicate with the access terminal. Therefore, the new femtocell service area will start sending requests for measurement reports to the access terminal (block 504), and will process the received measurement reports to control its transmit power (blocks 506-510). As the artisan walks along the designated training path, the operations of blocks 504-510 will be repeated at each femtocell service area in the femtocell service area network. In this way, all femtocell service areas will be calculated as the specific femtocell service area to provide an effective compromise between adequate coverage and sufficient macrocell service area protection.

When the skilled person completes the training walk, the effective call is terminated. For example, this may include the skilled person (for example, by activating the user input device) terminating the access terminal and/or the designated application on the femtocell service area.

Figure 6 illustrates exemplary operations that can be used in conjunction with an optimization procedure. This procedure may be performed by a designated femtocell service area among the femtocell service areas, by a network entity (e.g., BSC), or by some other method capable of obtaining the transmit power information generated during a training walk-based calibration procedure. Appropriate entities to perform.

As represented by block 602, once the calibration procedure based on training walking is completed, the optimization procedure is started. At this stage of the process, the transmit power value has been calculated for each femtocell service area in the femtocell service area network.

As represented by block 604, the information obtained as a result of the training walk calibration procedure is received. (For example, in a single entity that does not perform the two operations of the calibration procedure based on training walking and the optimization procedure, for example, after completing the calibration procedure based on training walking, the information can be automatically sent to perform the best The entity of the process. In some implementations, this information includes the calculated transmit power value for the femtocell service area during a training walk-based calibration procedure. In some implementations, the information includes one or more of path loss values, signal strength values (eg, pilot frequency strength), or signal quality indicators obtained from measurement reports received during the training walk calibration procedure.

As represented by block 606, the reconfiguration trigger condition is identified based on the received information. For example, the optimization trigger can be set based on the following: power difference, service path loss, power cap, coverage hole, or some other criterion.

In some implementations, it is determined at this stage whether the difference between the transmit power values of two femtocell service areas (for example, adjacent femtocell service areas) is greater than or equal to a threshold value (for example, 10 dB). In the case that the power difference is too high, reconfiguration of the femtocell service area can be triggered (for example, adding more femtocell service areas) to eliminate the FL/RL mismatch that may occur due to the power difference .

In some implementations, it is determined at this stage whether the number of path loss values greater than or equal to the threshold path loss is greater than or equal to the threshold number. As a specific example, the system may require that the path loss value should be less than 85 dB for at least 95% of the measurement report. In this way, the system can limit the size of the coverage area of the femtocell service area. Therefore, after determining that the excessive path loss value is too large, reconfiguration can be triggered.

At this stage, it can also be determined whether any femtocell service area reaches a threshold (e.g., maximum) power level. As a specific example, the system may require that any femtocell service area should not be allowed to operate at its maximum allowable power. For example, this criterion can be used to limit the size of the coverage area of a femtocell service area. Therefore, after one or more of the determined transmission power values reaches the threshold power level, reconfiguration can be triggered.

The skilled person can also perform a post-calibration walk to ensure satisfactory FL performance in the femtocell service area and beacon performance in the femtocell service area. For example, it can be determined at this stage whether there are any coverage holes in the coverage area of the femtocell service area network. In some cases, coverage holes can be identified by determining whether a call is interrupted in a certain area. If the coverage holes are identified, the skilled person can move the femtocell service area or insert more femtocell service areas to eliminate the coverage holes.

In some implementations, artisans identify coverage holes by monitoring the audio feedback on the access terminal during the training walk. For example, the artisan can place a call to another access terminal or server that provides audio feedback (e.g., a continuous audio track). Subsequently, the artisan can monitor the audio feedback for interruption of the call or noise (for example, clicks or pops), and record the location of such events. After identifying the coverage holes, the skilled person can reconfigure the femtocell service area to eliminate the coverage holes.

In some implementations, coverage holes are identified by monitoring signal quality (eg, pilot frequency signal strength) throughout the training walk. The monitoring can be performed by a skilled person, by an access terminal, by a femtocell service area, by a network entity, or some other suitable entity capable of receiving the signal quality information. For example, the access terminal can output the signal quality information obtained from its measurement report to a user interface device (for example, a display). Subsequently, the artisan can record the position where the signal quality information drops below the threshold to identify coverage holes. As another example, the access terminal can automatically compare the signal quality information it collects with one or more thresholds, and if applicable (for example, if the received signal quality is lower than the threshold for a certain percentage of the area), trigger a restart Configuration. As yet another example, an entity (e.g., femtocell service area, network entity, etc.) can automatically compare the signal quality information it receives via the measurement report with one or more thresholds, and trigger a restart if applicable. Configuration.

As represented by block 608, as a result of identifying the reconfiguration condition at block 606, an instruction to reconfigure the femtocell service area will be generated. For example, the entity performing the optimization operation can output instructions on the user interface device, or the entity can send a message to some other entity so that the entity (e.g., femtocell service area, access terminal, network Entities, management tools, web-based applications, etc.). After receiving the instruction, the skilled person can rearrange the femtocell service area and/or add another femtocell service area.

The skilled person can repeat the transmit power calibration procedure. For example, after calculating the transmission power during the initial training walk and/or after reconfiguring the femtocell service area, subsequent training walks may be performed. During this follow-up training walk, the above-mentioned information (for example, power value, path loss value, etc.) can be obtained and used for the transmission power optimization discussed in this case.

In the case where the power difference exceeds a specified limit (for example, 10 dB), the transmit power of the lower power femtocell service area can be increased to within the limit. In some cases, this operation can be performed without the intervention of a skilled person. For example, the entity performing the optimization operation can send a message to the appropriate femto cell service area to instruct the femto cell service area to adjust its transmit power (or if the entity is a femto cell service area that needs to adjust its power, Then the entity will trigger internal operations).

When the access terminal is relatively close to the access point (for example, a femtocell service area), the access terminal may not be able to obtain reliable measurement report information from another access point. In this case, FL transmission by a nearby access point may overwhelm the receiver of the access terminal.

In order to solve this problem, a co-located access point exchange solution as described in FIG. 7 can be used to obtain measurement report information. In some deployments, more than one macro cell service area is deployed in substantially the same location. In some cases, the co-located macro cell service area can use the same macro cell service area identifier on different frequencies. In addition, the macro cell service areas may transmit at the same or substantially the same power level (for example, within a few dB). Therefore, in the case that the access terminal cannot generate a measurement report for the first access point on the first frequency, the access terminal can measure the co-located second access point on another frequency, As an alternative to the first access point.

For example, the operation of FIG. 7 can be performed at an access point (e.g., femtocell service area) that receives measurement reports from the served access terminal, or at the network entity to which the measurement reports are sent ( For example, it is executed at the network entity that controls the transmit power of the femtocell service area. In addition, for illustrative purposes, these operations will be described in the context of co-located macro cell service area and control femto cell service area transmission power. However, it should be recognized that these concepts can also be applied to other types of access points.

As represented by block 702 in FIG. 7, the co-located access point switching scheme can be used for various types of transmit power calibration procedures. For example, such a solution can be used (for example, as described in Figure 4 above) for power calibration based on network monitoring, a calibration procedure based on training walking, or for other types of measurements.

As represented by block 704, it is determined that the measurement report associated with the first macro cell service area identifier is not being received from the first macro cell service area on the first frequency. For example, the failure to receive these measurement reports may be due to interference from a femtocell service area that is trying to receive measurement reports (for example, via NLM or via an access terminal), or due to another femtocell service District interference. In some cases, this decision can be made based on previous knowledge of the existence of the first macro cell service area. For example, an earlier calibration procedure may have successfully received a measurement report from the first macro cell service area on the first frequency. Therefore, subsequent calibration procedures will expect to receive measurement reports from the macro cell service area.

As represented by block 706, it is determined that the measurement report associated with the first macro cell service area identifier is received from the second macro cell service area co-located with the first macro cell service area on the second frequency. In some cases, the decision can be made as a result of starting a search on other frequencies after deciding that the measurement report is not received from the first macro cell service area. In other cases, measurements on multiple frequencies can be performed regardless of this decision.

As represented by block 708, as a result of the determination that the measurement report is not being received from the first macro cell service area, the femto cell service area may instead be controlled based on the measurement report received from the second macro cell service area The transmit power. For example, as discussed above, such a measurement report may include signal strength information, path loss information, etc., and the information may be used to adjust the transmission power to satisfy at least one criterion at the point where the measurement report is obtained. Therefore, as discussed in this case, the transmit power can be controlled to satisfy one or more of the following criteria: handover criteria, SNR criteria, macro cell service area protection criteria, pilot frequency signal quality criteria, adjacent Channel protection criteria or some other criteria.

In different implementations, various changes can be made to the described embodiments. In the above discussion, the beacon transmission power is calculated on the frequency of the first macro cell service area. The beacon transmission power for any other macro cell service area frequency can be calculated as an offset from the first macro cell service area frequency. Here, for example, the offset can be calculated based on the difference in received power for the macro cell service area of the different frequencies determined by using a network monitoring module or some other means. In this way, there is no need to perform additional training walks to obtain information on the frequency of other macro cell service areas.

In the above description, it is assumed that the access terminal performs multiple hard handovers during the training walk. However, in some 1x and DO femtocell service area networks, soft handover (SHO) is supported between femtocell service areas. In this scenario, the network entity (for example, BSC) decodes all measurement messages sent by the mobile station. It is also possible to configure the femtocell service area to be used as a BSC. The femtocell service area anchors the call and collects all measurement reports sent by the mobile station. In this type of deployment, the power calibration can be completed by several methods that are slightly different from the above-mentioned methods. For example, the anchor femtocell service area can (on the backload) distribute the collected reports to different femtocell service areas. Send to each femtocell service area all reports whose signal strength is the strongest or whose signal strength is within a certain margin (for example, "X"db) of the strongest femtocell service area. After receiving the measurement report, the femtocell service area uses the procedure described earlier to calibrate its power. Since there is a certain gain attributed to SHO in 1 x FL, the coverage performance target may be loose (for example, use a lower [1x_Ecp/Nt]_threshold). Or, by requiring each femtocell service area in SHO to transmit at a power inversely proportional to its path loss to the mobile station while covering a point in the SHO area, 1 x SHO gain in FL. Similarly, when the DO femtocell service area supports the femtocell service area SHO, the BSC (or the femtocell service area used as the BSC) will receive all measurement reports. In this case, as described above, the BSC can distribute reports among femtocell service areas based on the relative pilot frequency intensities of different femtocell service areas. In addition, when an entity collects all reports, the entity can use optimization to calculate the transmit power of the femtocell service area. For example, the total power in the system can be constrained within desired limits.

As discussed above, the femtocell service area can share the channel being used by the macrocell service area. In this case, the femtocell service area power on the service channel may have to be strong enough to attract users to the femtocell service area and also provide good SNR. As above, the beacon can be transmitted on the non-shared macro channel.

The disclosed power control technology can be used by IT staff or craftsmen in homeowners' residences, shops, and large enterprises. This kind of power control technology is suitable for single femto cell service area deployment and multi-femto cell service area deployment with closed or open access strategies.

If the information from all reports can be used by a network entity (for example, BSC), the network entity can execute the algorithm described in this case to calculate the optimal power level for good coverage and minimal macro network impact Then, the same power level is transferred to all femtocell service areas.

If the deployment is closed access, the report collection process may intensively originate from users in the effective femtocell service area. This may be problematic in open access deployments because users outside the expected coverage area may also be available on the femtocell service area. However, as discussed in this case, any undesired reports can be filtered out. In addition, the femtocell service area can use the login/communication period establishment statistics of users who are not in the whitelist as an indicator of external leakage, and adjust its power accordingly.

Examples for 1xRTT, 1xEV-DO, and UMTS have been described in detail. It should be recognized that the teachings of this case are also applicable to other wireless technologies. Therefore, the power control scheme taught in this case can be adopted in an LTE system or some other type of wireless system.

For illustrative purposes, additional details related to the calculation of the transmit power calibration for the 1xRTT implementation, the 1xEV-DO implementation, and the UMTS implementation will now be described.

<b>Exemplary details: 1xRTT transmit power calibration</b>

This section provides a deeper understanding of the SMART program. Assume that the femtocell service area is deployed on a dedicated channel adjacent to the macro channel. The dedicated channel means that the femtocell service area has its own (dedicated) RF frequency channel, which is different from the macro cell service area RF frequency channel. The changes made to the shared channel scenario will be described later, where in the shared channel scenario, the macro cell service area and the femto cell service area use the same RF frequency channel.

First, the number of femtocell service areas is determined based on the overall area to be covered and the expected coverage area of each femtocell service area. Place these femtocell service areas evenly, and be careful to keep them away from the edges to minimize the influence of the macro network. Some other factors that affect the above operations are: the shape and structure of the building; and the availability of Ethernet and GPS points that are indispensable for the function of the femtocell service area. The following provides specific steps for the calibration of the transmit (Tx) power of the 1xRTT femtocell service area.

1) Initialization:

The following steps are performed by each femtocell service area to use the network monitoring module to determine the initial power level (note that all the quantities described are in dBm or dB):

a) Tune the NLM to the adjacent macro frequency and measure the total received energy (<i>I</i><i>o</i>_{<i>macro_NL</i>})

b) Let<i>PL</i>_{<i>femto boundary_1x</i>}It is the target coverage area for initialization. Choose a higher target coverage area (for example, 100 dB) to ensure complete coverage before the power adjustment stage.

c) Calculate the required femtocell service area power based on the following equation: if the deployment is on a dedicated channel:

<i>P</i>_{<i>femto_init</i>}_{_1}_<i>x</i>=<i>Io</i>_{<i>macro_NL</i>}+<i>PL</i>_{<i>femto boundary</i>}_{_1}_<i>x</i>+C

C is a configurable parameter selected based on the target SNR, adjacent channel interference ratio, and some additional margin required by the transmit power.

If the deployment is in the same channel as the macro cell service area, the initial transmission power is calculated similarly. However, in this case, the macro cell service area measurement can be done on the same channel instead of on the adjacent channel.

Once all femtocell service areas have implemented NLPC, the maximum value of these NLPC values is obtained:

<maths><img file="TW201216748A_D0001.tif" /></maths>

Now initialize each femtocell service area to the value provided by the following equation:

<i>P</i>_{<i>femto,init</i>}=<i>P</i>_{<i>femto_init</i>}_{<i>_</i>}₁_<i>x</i>+<i>min</i>(<i>CAP</i>_<i>init</i>,<i>P</i>_{<i>femto_init_max</i>}-<i>P</i>_{<i>femto_init_</i>}₁_<i>x</i>)

Here, CAP_initIt is a configurable value (for example, 15 dB). The goal here is to have the same initial power on all femtocell service areas, but keep a limit on the increase in power from the initial NLPC value. The NLPC algorithm achieves a good compromise between these two opposing requirements.

This kind of algorithm can be done manually by the skilled person, or the femtocell service areas can transmit their power to each other on the back load, and all the femtocell service areas select the maximum value. Note that initialization can also be done in different ways. For example, all femtocell service areas can be set to their maximum possible transmit power level. However, since using the maximum transmit power may cause high interference, it is not recommended to do so.

2) Power adjustment:

This is the most important stage of the femtocell service area deployment process and helps to tune the power of all femtocell service areas to the desired level. The power adjustment is explained in a few simple steps.

After the initialization, the call is initiated on the femtocell service area channel, and the effective mobile station is brought to all areas of the house/business that are expected to be covered. This is done to collect RF measurement values from each place and set the best power value.

During the dialing period, the femtocell service area uses standard signal transmission procedures and requests mobile stations to periodically submit measurement reports. The two measurement reports used (defined in the cdma2000 1xRTT standard) are: 1) Pilot frequency strength measurement messages (PSMMs): As part of the PSMM, the mobile station reports what it can detect on its operating frequency Ecp/Io and total received energy Io of each femtocell service area PN (false random noise sequence or code). If the deployment is in the same channel, the macro cell service area on the channel is also reported in PSMM; 2) Candidate Frequency Search Report Messages (CFSRPMs): Femtocell services are part of the Candidate Frequency Search (CFS) program The zone requests the mobile station to tune to the specified macro frequency, and report in CFSRPM the Ecp/Io of each macro PN that it can detect and the total received energy Io.

Obtain these reports from the mobile station periodically (for example, every 2-3 seconds) to get a good sampling of the area. The PSMM and CFSRPM messages that arrive within a short time from each other are combined to form a measurement report. The femtocell service area can synchronize the requests of these messages with time (for example, by scheduling the requests intensively in time, by using the ACTION_TIME field available in the CFS request message, etc.) to make these The messages arrive a short time apart.

Femtocell service areas use mobile station reports to calculate the power required to provide good coverage at each reporting point. Suppose that during the training walk, when the intensity of the femtocell service area changes, the mobile station performs a hard handover between the femtocell service areas, and the PSMM is always sent to the service femtocell service area. Set the handover lag to 0 dB to ensure that the serving femtocell service area is always the strongest femtocell service area, but this parameter can be adjusted. (Note that the hysteresis value can be configured with the help of different parameters such as T_ADD, ADD_INTERCEPT, etc., available in the 1xRTT standard.) Finally, each femtocell service area forms a report (point) subset, in which the report (point) In the) subset, the reception intensity of the femtocell service area is the highest among all femtocell service areas, and each femtocell service area attempts to provide coverage at the point where the reports are obtained. The femtocell service area calculates the beacon power and femtocell service area power required at all these points in the following way, and then selects the power value for these channels:

<b>Beacon power:</b>

In order to facilitate the delivery of idle action stations, the strength of the beacon at the reporting point needs to be higher than the lagging margin of the strongest macro cell service area1<i>x_beacon</i>_<i>hyst</i>. For the "i" measurement report, use the following equation to calculate the required beacon transmit power:

<maths><img file="TW201216748A_D0002.tif" /></maths>

Here,<img file="TW201216748A_D0003.tif" />(<i>i</i>) Is the strength of the guidance frequency of the strongest macro cell service area from the "i" CFSRPM report, and it is calculated by adding the Ecp/Io and Io measured by the mobile station. K is based on the typical handover The lag value and the constant of the required transmit power margin,<i>PL</i>_{<i>report</i>}(i) is the path loss to the reporting point, and it is calculated using the PSMM report using the following equation:

<i>PL</i>_{<i>report</i>}=<i>P</i>_<i>femto</i>+<i>Ecp</i>/<i>Ior</i>_<i>femto</i>-(<i>Ecp</i>/<i>Io</i>_<i>PSMM</i>+<i>Io</i>_<i>PSMM</i>)

Here,<i>Ecp</i>/<i>Ior</i>_<i>femt</i>. It is the ratio of the power of the pilot channel to the total transmit power on the FL channel of the femtocell service area.

Therefore, a set of power levels required to provide beacon coverage at all reporting points is formed {<i>P</i>_{<i>beacon</i>}_{_1}_<i>x</i>(i)}.

The femtocell service area can use a hierarchical beacon design scheme. For this hierarchical beacon design solution, the high beacon transmission power and the low beacon transmission power are selected as certain statistical values (for example, the median, average, maximum, or certain percentage value of the set). The statistical value selected for high power is higher than for low power beacons.

Since reselection to the femtocell service area channel only requires one beacon, in order to minimize the impact on users of the macrocell service area, the coverage target is kept low.

When the femtocell service area is deployed in the same channel as the macrocell service area, the beacon power also depends on the femtocell service area power. Set the femtocell service area power in the same channel appropriately to protect the macro. Therefore, it is important to keep track of the femtocell service area power, because if the beacon coverage is greater than the femtocell service area coverage, it will cause idle delivery to fail. Femto cell service area power is used to calculate the limit on high beacon power so that the high beacon coverage is smaller than the femto cell service area.

Since the beacon power depends on the power of the femto cell service area, in the same channel deployment, the femto cell service area power is calculated before the beacon power is calculated.

<b>Femto cell service area power:</b>

The algorithm used for femtocell service area power calibration depends on the type of deployment: dedicated channel or same channel.

<b>Dedicated deployment where the macro cell service area is located on the adjacent channel:</b>

The power of the femtocell service area is set to provide good coverage to users of the femtocell service area, while limiting the interference caused to the users of the macrocell service area on adjacent channels.

<b>a) Coverage constraints:</b>

In order to provide good coverage, the femtocell service area power is set to reach the target SNR at the reporting point (1x_Ecp/Nt_{<i>threshold</i>}). The interference here is caused by leakage from adjacent macro channels. Use the following equation to calculate the power required for the "i" report point:

<maths><img file="TW201216748A_D0004.tif" /></maths>

Here,<img file="TW201216748A_D0005.tif" />(<i>i</i>) Is the total interference on the macro channel. In order to eliminate the leakage from the femtocell service area channel, the total interference is calculated by adding the energy of all reported macros. As mentioned above,<i>PL</i>_{<i>report</i>}(i) is obtained from PSMM, and C is a constant factor determined by the combination of the adjacent channel leakage ratio, the required SNR target, and some additional margin required for the transmit power. In this calculation, interference from other femtocell service areas is excluded, and the interference is mitigated by including an appropriate margin in the parameter C. This is important to prevent power contention (if each femtocell service area tries to overcome the interference caused by other femtocell service areas, power contention may occur).

The femtocell service area is now selected according to the following equation to ensure that most reporting points are well covered (only outsiders are not considered):

<i>P</i>_{<i>femto_coverage</i>}_{_1}_<i>x</i>={<i>P</i>_<i>femto</i>_{_1}_<i>x</i>(<i>i</i>)}of<i>CDF</i>Middle Cov_femto% Value,

Here, {<i>P</i>_<i>femto</i>_{<i>_</i>}₁_<i>x</i>(<i>i</i>)} is the set of power calculated for all reporting points, Cov_femtoIt is configurable, and 95 is usually selected.

<b>b) Macro protection constraints:</b>

When the femtocell service area is operating on a channel adjacent to the macro, interference will continue to hinder users of the macrocell service area. This is especially important when deployed as closed access. In order to keep the impact controllable, the femtocell service area sets its power so as to limit the contribution of its power to the macro cell service area interference to only a small part of the macro cell service area interference (by<i>Io</i>_ΔExpress). This setting can be done as follows:

For each reporting point, calculate the power limit as provided by the following equation:

<maths><img file="TW201216748A_D0006.tif" /></maths>

Here, Z is a constant that determines the required protection level of the macro cell service area. The femtocell service area calculates the power limit of a point for protecting a certain part (for example, 50%). The uniform sampling of this area ensures that users of the macro cell service area on adjacent channels are protected in 50% of the area surrounding the femto cell service area.

<i>P</i>_{<i>femto_protection</i>}_{_1}_<i>x</i>={<img file="TW201216748A_D0007.tif" />(<i>i</i>)) Cumulative Distribution Function (CDF) in Prot_macro% Value

Parameters Prot_macroIt is configurable, and is selected as 50 in some implementations.

The final femtocell service area power is selected as the minimum value of coverage and macrocell service area protection.

<b>Same channel deployment:</b>

In this scenario, the femtocell service area signal is used to provide coverage for femtocell service area users, and is also used to trigger the macrocell service area users on the same channel to reselect to the femtocell service area. Therefore, the femtocell service area signal also has the same effect as a beacon. The power setting takes into account these two requirements at each point.

<b>a) SNR constraints:</b>

The SNR of the femtocell service area at the target point should be equal to the configured threshold-<i>SINR</i>_{<i>femio,max</i>}. therefore:

<maths><img file="TW201216748A_D0008.tif" /></maths>

Here, according to the SNR target<i>SINR</i>_{<i>femto,max</i>}And the desired extra margin in the transmit power to select C.

<b>b) Idle handover constraints:</b>

The strength of the guidance frequency of the femtocell service area is set to be higher than the strength of the guidance frequency of the best macro cell service area by a hysteresis margin. This is done to keep the corporate boundary between the idle delivery boundary and the idle distribution boundary of the same channel mobile station. This means that most users within the enterprise will be able to reselect from the macro channel to the femtocell service area channel. And secondly, once on the femtocell service area channel, as long as the user is inside the enterprise, the user will not return to the macro network. The exact position of the boundary is controlled by the hysteresis value. therefore:

<i>Ptx</i>_{<i>handoff</i>}(<i>i</i>)=<i>Ecp</i>_{<i>best macro,report</i>}(<i>i</i>)+<i>PL</i>_{<i>report</i>}(<i>i</i>)+K

<i>Ptx</i>_<i>temp</i>(<i>i</i>)=<i>max</i>(<i>P</i>_<i>femto</i>_{_1}_<i>x</i>(<i>i</i>),<i>Ptx</i>_{<i>handoff</i>}(<i>i</i>))

Here, K is selected based on a typical handover lag and some extra margin in the transmit power value.

Choosing the maximum value of power at each point ensures that the power at each point meets both the coverage constraint and the idle handover constraint.

The femtocell service area is now selected according to the following equation to ensure that most reporting points are well covered (only outsiders are not considered):

<i>P</i>_{<i>femto_coverage</i>}_{_1}_<i>x</i>={<i>P</i>_<i>femto</i>_{_1}_<i>x</i>(<i>i</i>)} CDF in C<i>ov</i>_femto% Value

Here, {<i>P</i>_{<i>femyo_1x</i>}(<i>i</i>)} is the set of power calculated for all reporting points, Cov_femtoIt is configurable, and 95 is selected in some implementations.

3) Power optimization:

By triggering certain event triggers/alarms such as triggers for incorrect locations, insufficient coverage, reverse link performance impact, etc., the femtocell service area power is fine-tuned to achieve optimal performance. Some examples of these triggers are described as follows:

Power difference: The power difference between two femtocell service areas that share a coverage boundary should not be greater than 10 dB. This is important to minimize the FL/RL imbalance.

Service path loss: The part of the path loss value exceeding 85 dB (each femtocell service area gets a measurement report based on it) should be less than 5%. Note that it is possible to obtain these path loss values from the skilled persons walk before the transmit power adjustment, or by performing a new walk and collecting a new report set (where the femtocell service area uses its newly calculated transmit power value Transmit) to obtain these path loss values. This optimized trigger ensures that the coverage area of each femtocell service area is limited to 85 dB. If the coverage is extended beyond this point, users in the femtocell service area at the edge may transmit at very high power to maintain their links, and may cause undesired highs to nearby macrocell service areas. ROT (Thermal Noise Increase).

Power limit: any femtocell service area should not reach the maximum power limit on the beacon channel or femtocell service area channel, because this indicates that the coverage criterion cannot be met at several points.

If any of these conditions are triggered, the location of several femtocell service areas will be changed, or another femtocell service area will be added to the triggering area. Thereafter, the entire calibration procedure will be repeated.

<b>Exemplary details: 1xEV-DO transmit power calibration</b>

This section describes other aspects of the SMART program embodiment and how to deploy the SMART program in the implementation of 1xEV-DO (for example, it may be called EV-DO or simply DO in this case). In this example, it is assumed that the DO femtocell service area is deployed on a channel shared with the macro channel, or a dedicated channel is separately set up for the DO femtocell service area. For a dedicated deployment, it is assumed that the femtocell service area is deployed on a dedicated channel adjacent to the macro channel. In SMART deployed for dedicated DO, femtocell service area beacons are transmitted on the macro channel. Perform the following steps in conjunction with the 1xSMART program:

1) Initialization:

Femto cell service area power:

Femto cell service area i measurement Io_macro,NLM,i(dBm), the Io_macro,NLM,iIt is the total macro cell service area RSSI measured on the operating frequency of the femto cell service area. If the macro cell service area is not detected, the Io_macro,NLM,iSet as the thermal noise base. Subsequently, the femtocell service area calculation is used to_edge,femto(E.g., 90 dB) represents the P that provides coverage in the area_i：

<i>P</i>_<i>i</i>=<i>K</i>+<i>Io</i>_<i>m</i>_{<i>acro,NLM,i</i>}+<i>PL</i>_{<i>edge,f</i>}_em_<i>to</i>

Here, K depends on the required Ecp/Nt target and the extra margin expected in the transmit power value.

Subsequently, the temporary transmit power of the femtocell service area i is calculated according to the following equation:

<i>P</i>_{<i>femto,DO,i</i>}=<i>min</i>(<i>max</i>(<i>P</i>_<i>i</i><i>,P</i>_{<i>minfemto</i>})<i>,P</i>_{<i>maxfemto</i>})

Here, P_min,femtoAnd P_max,femtoThey are the minimum and maximum allowable transmit power levels (in dBm) of the femtocell service area.

Once all the femtocell service areas output their respective NLPC power, the skilled person will determine the initial power to be used by each femtocell service area as follows. Use the following representation:

<i>P</i>_{<i>femto,init,max</i>}=<i>max</i>_<i>i</i>(<i>P</i>_{<i>femto,i</i>})。

Femtocell Service Area<i>i</i>The initial power is:

<i>P</i>_{<i>femto,DO,init,i</i>}=<i>P</i>_<i>femto</i>_,_<i>DO</i>_<i>,</i>_<i>i</i>+<i>min</i>(<i>CAP</i>_{<i>init,DO</i>},<i>P</i>_<i>femto</i>_,_<i>DO</i>_<i>,</i>_<i>init</i>_,_<i>max</i>-<i>P</i>_{<i>femto,DO,i</i>})

Here,<i>CAP</i>_{<i>into,DO</i>}Is a constant (for example, 15 dB), which sets the upper limit of the allowable power increase. This method allows artisans to not violate<i>CAP</i>_{<i>into,DO</i>}Under the premise of increasing the limit, increase the initial power of each independent femto cell service area to be as close as possible<i>P</i>_{<i>femto,DO,init,max</i>}。

This femtocell service area power initialization is applicable to both same-channel deployment and dedicated deployment, but some parameters may be different, for example, PL_edge,femto。

Beacon power:

A similar algorithm is also executed at each femtocell service area to determine the initial beacon power: Femtocell service area i measures Io_beacon,NLM,i(dBm), the Io_beacon,NLM,iIt is the total macro cell service area RSSI measured on the operating frequency of the macro cell service area. Subsequently, the femtocell service area is calculated by the PL_edge,beacon(For example, 95 dB) the "i" that provides beacon coverage in the area indicated:

<i>P</i>_<i>i</i>=<i>K</i>+<i>Io</i>_{<i>beacon,NLM,i</i>}+<i>PL</i>_{<i>edge,beacon</i>}

Here, K is selected according to the desired beacon pilot frequency strength (Ecp/Io) at the coverage edge of the femtocell service area and some extra margin of the transmit power value. As far as the beacon is concerned, coverage simply means that the beacon should be searchable during the power adjustment phase assisted by the craftsman.

Subsequently, the temporary transmit power of beacon i is calculated as follows:

<i>P</i>_{<i>femto,Do,init,i</i>}=<i>min</i>(<i>max</i>(<i>P</i>_<i>i</i><i>,P</i>_{<i>min,beacon</i>}),<i>P</i>_{<i>imax,beacon</i>})

Here, P_min,beaconAnd P_max,beaconThey are the minimum and maximum allowable transmit power levels of the beacon, in dBm.

Unlike the femtocell service area power, the beacon of each femtocell service area can have a different value without taking a maximum operation with an upper limit. This is done to minimize the influence of the beacon on the Ecp/Io measurement value of the macro cell service area, thereby reducing the risk of Ecp/Io reporting problems in the femto cell service area/macro cell service area.

The beacon power initialization is applicable to both the same channel deployment and dedicated deployment, but some parameters may be different, for example, PL_edge,beacon。

2) Power adjustment:

This is the most important stage of the femtocell service area deployment process and helps to tune the power of all femtocell service areas to the desired level. The power adjustment is explained in several steps.

After initialization, start the data communication period on the femtocell service area channel, and bring the effective mobile station to all the areas expected to be covered in the house/business. This is done to collect RF measurement values from each place and set the optimal power value.

During the dialing period, the femtocell service area uses standard signal transmission procedures and requests mobile stations to periodically submit measurement reports. These requests are sent using route update request messages. The report message used is a route update message (RUM). In RUM, the access terminal reports the Ecp/Io of all PNs that the access terminal can detect on its operating frequency and the requested frequency. For example, these reports are obtained from the mobile station every few seconds to get a good sampling of the area.

However, unlike the 1xRTT case, the EV-DO access terminal report only contains the Ecp/Io of each sector, not the Io measurement value. This means that for EV-DO Femtocell service area and beacon power calibration, direct path loss reporting is not available, which is the main difference from 1xRTT SMART.

The following EV-DO SMART algorithm explains how to use DO macro cell service area and beacons Ecp/Io report to calculate the femto cell service area and information that meet a certain criterion when these reports can be obtained through walking training by artisans. Standard transmit power. When such reports are not available, the 1xRTT access terminal report can be used to calculate the femtocell service area and beacon transmission power.

The idea of power calibration is to use mobile station reports to calculate the power required to provide good coverage at each reporting point. In this example, it is assumed that during the training walk, when the intensity of the femtocell service area changes, the mobile station performs a hard handover between the femtocell service areas, and the RUM is always sent to the service femtocell service area. If hard handover is supported, set the handover hysteresis to (for example, 0 dB) Ensure that the serving femtocell service area is always the strongest femtocell service area (however, this parameter can be adjusted). The hysteresis value can be configured with the help of different parameters available in the DO standard (for example, PilotAdd, AddIntercept, SoftSlope, PilotCompare, etc.). If hard handover is not supported and no soft handover occurs, the serving femtocell service area can redirect the access terminal to the strongest femtocell service area based on the measurement report it receives. For example, when the reports indicate that the target femto cell service area has become stronger, the serving femto cell service area may send a connection close command, wherein based on the connection close command, the access terminal closes the connection, enters an idle state, and restarts. Select the target femtocell service area, establish a data connection and continue to send reports. If soft handover is supported, some femtocell service areas will not only collect their reports that serve the femtocell service area (that is, the strongest femtocell service area), but also collect another femtocell service District is the strongest other report. In this case, the femtocell service area can either directly redistribute the report to the corresponding strongest femtocell service area, or send all the reports to the control center (for example, a centralized entity), where the The control center is responsible for collecting all reports and redistributing them to the corresponding strongest femtocell service area. By any of the above methods, finally, each femtocell service area forms a report (point) (in these reports (points), the reception intensity of the femtocell service area is equal to that of all femtocells in the report. The highest subset of the service area) and attempts to provide coverage at the point where the reports are obtained. Each femtocell service area calculates the beacon and femto power required at all such points, and then selects the power as follows:

<b>Same channel deployment</b>

Femto cell service area power:

On the basis of considering the influence of femtocell service area power on the same channel macro, adjust the femtocell service area power. This power should be sufficient to provide idle mode and active mode coverage to access terminals that are being served by the femtocell service area. In order for the user to stay resident in the femtocell service area, the signal strength of the femtocell service area should not be much weaker than the signal strength of the strongest macrocell service area, otherwise, the access terminal will execute the macro Idle handover. The signal strength of the femtocell service area may be weaker than the amount of the macrocell service area (and the amount is such that it remains resident in the femtocell service area) depending on the hysteresis value used to perform idle handover. The typical value is 3-5 dB. After considering this point, perform power adjustment as follows:

<b>Idle distribution constraints:</b>

Femto Cell Service Area<i>i</i>Construct a set of increments or decrements of transmit power for each reporting point {<i>P</i>_{<i>delta,temp1,i</i>}} In order to meet the idle handover coverage constraint at this reporting point. For the "j"th report, the construction is completed as follows:

<maths><img file="TW201216748A_D0009.tif" /></maths>

Here, it is selected according to a certain expected extra margin among the typical idle handover hysteresis value and the emission margin<i>K</i>，<i>Ecp</i>/<i>Io</i>_{<i>best macro,i</i>}(<i>j</i>) Is the best (strongest in terms of Ecp/Io) Ecp/Io of the macro cell service area reported in the j-th measurement report, and (<i>Ecp</i>/<i>Io</i>)_{<i>femto,i</i>}(<i>j</i>) Is the Ecp/Io of the femtocell service area reported in the j-th measurement report. exist<i>Hyst</i>_<i>femto</i>In the case of -5 dB, an idle handover occurs from the femto cell service area to the macro cell service area, and the<i>Hyst</i>_<i>femto</i>In the case of 5 dB, an idle handover occurs from the macro cell service area to the femto cell service area.

Femto Cell Service Area<i>i</i>will<i>P</i>_{<i>feminc,temp1,i</i>}Calculated as<i>P</i>_{<i>delta,temp1,i</i>}Percent of the CDF of the value set<i>Cov</i>_{<i>femto,DO</i>}(For example, 95%). This will ensure that<i>Cov</i>_{<i>femto,DO</i>}The reporting points meet the idle handover conditions.

Femto Cell Service Area<i>i</i>Calculate the calibrated transmit power as follows:

<i>P</i>_{<i>femto_temp</i>}₁_<i>,i</i>=<i>P</i>_{<i>femto,DO,i</i>}+<i>P</i>_<i>fe</i>_min_{<i>c,temp</i>}₁_<i>,i</i>

<b>SNR constraints:</b>

Femto node<i>i</i>Construct a set of increments or decrements of transmit power for each reporting point {<i>P</i>_{<i>delta,temp2,i</i>}} In order to meet the SNR coverage constraint at this reporting point. Based on the pilot frequency strength of the macro cell service area and femto cell service area reported in the "j" report, calculate the required increment or decrement for the "j" report. Femto Cell Service Area<i>i</i>will<i>P</i>_{<i>feminc,temp</i>}₂_<i>,i</i>Calculated as<i>P</i>_{<i>delia,temp2,i</i>}Percent of the CDF of the value set<i>Cov</i>_{<i>femto,DO</i>}(For example, 95%). This will ensure that<i>Cov</i>_{<i>femto,DO</i>}The reporting points meet the idle handover conditions.

Femto Cell Service Area<i>i</i>Calculate the calibrated transmit power as follows:

<i>P</i>_{<i>femto_temp2,i</i>}=<i>P</i>_{<i>femto,DO,i</i>}+<i>P</i>_{<i>feminc,temp2,i</i>}

Finally, set the femtocell service area power to:

<i>P</i>_{<i>femto,temp,i</i>}=<i>max</i>{<i>P</i>_{<i>femto_temp</i>}₁_<i>,i</i><i>,P</i>_<i>f</i>_{<i>emto_temp</i>}₂_<i>,i</i>}，

<i>P</i>_{<i>femto,final,i</i>}=min(max(<i>P</i>_min,_<i>femto</i>,<i>P</i>_<i>f</i>_{<i>emto,temp,i</i>}),<i>P</i>_max,_<i>femto</i>)

Here,<i>P</i>_{<i>min,femto</i>}and<i>P</i>_{<i>max,femto</i>}It is the absolute minimum configuration value and the absolute maximum configuration value of the transmit power of the femto cell service area.

The above calculation of femtocell service area power is based on EV-DO home access terminal (femtocell service area) measurement reports. These measurement reports include different sectors (macro cell service area, femtocell service area and / Or beacon) Ecp/Io. When these EV-DO reports are not available, the aforementioned power calculation cannot be performed in this way. In this scenario, people can reuse the 1xRTT home access terminal measurement report (if available), and perform EV-DO power adjustment based on the 1xRTT report. This method assumes that both 1xRTT and EV-DO technologies are available on the same femtocell service area, and both 1xRTT and EV-DO power adjustments are performed. This is a very likely scenario.

In the following method, only the path loss information in all signal measurement values in the 1xRTT home access terminal report is used, where the path loss information is calculated based on the Ecp/Io report and the Io report. However, other measurement values or information contained in the 1xRTT home access terminal report can also be used to adjust the EV-DO power.

First, the power adjustment algorithm uses all the path loss reports collected during the 1xRTT measurement report collection phase to calculate {<i>PL</i>_{<i>femto,i</i>}(<i>j</i>)} Cumulative Distribution Function (CDF). Subsequently, the algorithm calculates<i>PL</i>_<i>edge</i>_,1_<i>x</i>={<i>PL</i>_{<i>femto,i</i>}(<i>j</i>)} percent of the CDF<i>CovPer</i>_<i>PL</i>_<i>edge</i>Value.

Get PL_edge,1xAfter that, the power adjustment algorithm repeats the part of the femto power initialization procedure described above. This part of the program starts with the headings listed above: "1) Initialization:" and "Femtocell service area power:", and includes the words "Where P_min,femtoAnd P_max,femtoAre the minimum and maximum allowable transmit power levels..." the end of the four paragraphs (for example, about 00192-00195 paragraphs). Note that the rest of the initialization procedure is not performed here. The operations that are not performed include three paragraphs starting with "Once all femtocell service areas output their respective NLPC power..." (for example, about paragraphs 00196-00198). When repeating the part of the initialization program mentioned in the previous few sentences, the program will use<i>PL</i>_<i>edge,</i>₁_<i>x</i>replace<i>PL</i>_{<i>edge,femto</i>}. Set the output power level<i>P</i>_{<i>femto,DO,i</i>}(<i>PL</i>_<i>edge,</i>₁_<i>x</i>) Set as femtocell service area power:

<i>P</i>_{<i>femto,final,i</i>}=<i>P</i>_{<i>femto,DO,i</i>}(<i>PL</i>_<i>edge,</i>₁_<i>x</i>)。

Beacon power:

For each macro channel that needs to be calibrated for proper beacon power, the femtocell service area will activate the NLM module to measure the macro cell service area Ecp/Io on the beacon channel. Assuming in frequency<i>fi</i>When transmitting a beacon, set the transmit power of the beacon relative to the transmit power of the femtocell service area in the following manner:

<i>P</i>_{<i>beacon,fi,temp</i>}=<i>P</i>_{<i>femto,final,i</i>}+K

<i>P</i>_{<i>beacon,final,i</i>}=min(max(<i>P</i>_{<i>min,beacon</i>},<i>P</i>_{<i>beacon,fi,temp</i>}),<i>P</i>_{<i>max,beacon</i>})

Here,<i>P</i>_{<i>femto,final,i</i>}Is the calibrated transmit power of femtocell service area; frequency measured according to NLM<i>fo</i>K is selected by the difference between the guide frequency intensity of the macro cell service area on the frequency fi and the guide frequency intensity of the macro cell service area on the frequency fi and a certain expected extra margin in the transmit power. The extra margin is used to reduce the users failure to obtain the femtocell service area signal due to the downfade of the femtocell service area signal while performing idle delivery according to the beacon due to the beacon upfade. The probability of the event.

<b>Dedicated deployment</b>

Femto cell service area power:

In order to provide good femtocell service area coverage while avoiding leakage to adjacent channels on which the macrocell service area may operate, dedicated femtocell service area power calibration includes two constraints:<i>Femto cell service area coverage and macro cell service area protection</i>. More specifically, the following procedure is performed for femtocell service area power calibration:<i>S</i>_<i>i</i>For serving areas in femtocells<i>i</i>A collection of reports received from the femtocell service area frequency and beacon frequency, the collection of reports containing the Ecp/Io measurement values from each sector. If there is no special mark, all specified variables are in the dB domain.

Femtocell service area coverage constraints

Calculate the transmit power required to provide good coverage (for example, defined as having SNR&gt;5 dB) as follows:

Femto Cell Service Area<i>i</i>Construct the collection as follows<i>P</i>_<i>temp</i>_1,_<i>i</i>：

<maths><img file="TW201216748A_D0010.tif" /></maths>

Here, (<i>Ecp</i>/<i>Io</i>)_{<i>macro,k,</i>}_i(<i>j</i>) In the linear domain, which means<i>S</i>_<i>i</i>The Ecp/Io of the k-th macro cell service area reported in the j-th report, and (<i>Ecp/Io</i>)_{<i>beacon,i,i</i>}(<i>j</i>)Yes<i>S</i>_<i>i</i>Ecp/Io of the i-th beacon reported in the j-th report.<i>P</i>_<i>B,i</i>Is the beacon power of the i-th femtocell service area after initialization, and K depends on the desired SNR target and some desired extra margin in the transmit power value. This constraint ensures that the position corresponding to the report does not receive a signal quality higher than a certain SNR (for example, 5 dB). This prevents unnecessary interference.

The femtocell service area i calculates the transmit power corresponding to the constraint in the following way:

<i>P</i>_{<i>femto,coverage,i</i>}= Percent<i>Cov</i>_<i>femto</i>(E.g. 95%)<i>P</i>_<i>temp</i>₁_<i>,i</i>That is, for 95% of the reports, the power will meet the coverage constraint.

Macro protection constraints:

Calculate the transmit power that can be used and protect the adjacent channel macro cell service area as follows:

Femtocell service area i constructs a set as follows<i>P</i>_{<i>temp2,i</i>}：

<maths><img file="TW201216748A_D0011.tif" /></maths>

Here, C depends on the protection level (for example, 5 dB lower than the service area strength of the macro cell) and some extra margin.

Subsequently, the femtocell service area i calculates the transmit power corresponding to the constraint as follows:

<i>P</i>_{<i>femto,proteciion,i</i>}= Percent<i>Prot</i>_<i>macro</i>of<i>P</i>_<i>t</i>_<i>emp</i>₂_<i>,i</i>

Subsequently, the power of each femtocell service area is calculated as follows:

<i>P</i>_{<i>femto,final,i</i>}=min(max(min(<i>P</i>_{<i>femto,coverage,i</i>},<i>P</i>_{<i>femto,protection,i</i>}),<i>P</i>_min,_<i>femto</i>),<i>P</i>_max,_<i>femto</i>)

Similar to the same channel deployment, if the two technologies coexist in the same femtocell service area, and the 1xRTT home access terminal measurement report has been collected for 1xRTT power adjustment, it can also be based on the 1xRTT home access terminal measurement report To calibrate the femtocell service area power. In addition, although only path loss information is used in the following procedure, other measurement reports can also be used in the calculation.

Beacon power:

In order to facilitate the delivery of idle action stations, the strength of the beacon at the reporting point should be higher than the lagging margin of the strongest macro cell service area<i>beacon</i>_{<i>hyst,DO</i>}. To achieve this, the femtocell service area<i>i</i>Construct a set of increments or decrements of transmit power for each point {<i>P</i>_{<i>delta,i</i>}} In order to satisfy the idle handover coverage constraint at this point. Calculate the power value as follows:

<maths><img file="TW201216748A_D0012.tif" /></maths>

Here, (Ecp/Io)_beacon,i(j) is to<i>i</i>Sent by the femtocell service area<i>j</i>Ecp/Io of the i-th beacon reported in each report. Parameters (Ecp/Io)_bestmacro,i(j) is the Ecp/Io of the best macro cell service area reported in the jth report sent to the i-th femtocell service area, and K is based on the typical handover lag and some additional transmit power The margin to choose.

Femto Cell Service Area<i>i</i>will<i>P</i>_<i>inc,i</i>Calculated as<i>P</i>_{<i>deita,i</i>}Percent of the CDF<i>Co</i>ν_{<i>beacon,DO</i>}(For example, 80%). This will ensure that<i>Co</i>ν_{<i>beacon,DO</i>}The report meets the idle handover conditions.

Femto Cell Service Area<i>i</i>Calculate the calibrated transmit power of its beacon as follows:

<i>P</i>_{<i>beacon, final, DO, i</i>}=<i>P</i>_{<i>beacon,DO</i>}+<i>P</i>_<i>inc,i</i>

As mentioned above, another way is to reuse<b>1xRTT</b>The home access terminal measures the report to calculate the beacon transmit power. In some aspects, the method is similar to the calculation of the service area power of femtocells in the same channel based on the 1xRTT home access terminal measurement report. First, formulate the {<i>PL</i>_{<i>femto,i</i>}(<i>j</i>)},calculate<i>PL</i>_<i>edge,</i>₁_{<i>x,temp</i>}={<i>PL</i>_{<i>femto,i</i>}(<i>j</i>)} percent of the CDF<i>CovBcn</i>Then, upper and lower limits are imposed on the allowable path loss target, and finally for the new path loss target<i>PL</i>_<i>edge,</i>₁_{<i>x,temp</i>}Dedicated deployment to repeat the beacon NLPC. Set the calculated power as the final beacon power<i>P</i>_{<i>beacon,final,DO,i</i>}。

Once all femtocell service areas have adjusted their power based on this method, the next step is to optimize the power levels.

3) Power optimization:

The same operation as described in this case (for example, the operation for 1xRTT) can be used to complete the power optimization.

<b>Exemplary details: UMTS transmit power calibration</b>

This section describes other aspects of the SMART program implementation in the UMTS implementation and how to deploy the SMART program.

Parameter initialization in power calibration mode

For the power calibration mode, an example of a set of parameters that can be used is provided below. Set the MRM report interval and the MRM report amount to 250 ms and infinity, respectively, so as to periodically receive measurement reports at short intervals and long durations. In addition, soft handover (SHO) can be disabled during walking training for the craftsperson.

If SHO is not disabled, reports can still be collected at each femtocell service area, or sent to a femtocell service area (for example, a femtocell service area used as a cluster head) or to a separate entity. The described algorithm is applicable to either situation.

(For example, if SHO is disabled) Effective dialing handover can be managed via hard handover. For handover between femtocell service areas, for example, a hysteresis-CIO value of 0 dB may be used. This allows the femtocell service area to collect reports from areas where the femtocell service area may be the strongest. For the handover to the macro cell service area, for example, a hysteresis-CIO value of 6 dB can be used. This will allow the femtocell service area to obtain reports from those areas where the macrocell service area is stronger than the femtocell service area.

<b>Transmit power initialization</b>

Each femtocell service area uses the desired coverage (as input) and the RSSI measurement value of the macrocell service area obtained using NLM. The transmit power of the femtocell service area is selected to meet the coverage requirements. For example, in the coverage area, the CPICH of the femtocell service area can be<i>E</i>_<i>c</i><i>/Io</i>Defined as better than<i>Q</i>_{<i>qualmin, femto</i>}. In addition, in order to limit the interference to the downlink of the macro cell service area, the femto cell service area transmission can be restricted to at most only a fixed increase in the macro cell service area Io at the edge of the femto cell service area coverage. quantity. Therefore, the following conditions are met at each femtocell service area:

<b>Coverage conditions:</b>

The transmit power of the femtocell service area is selected to meet the idle reselection requirement at the edge of the coverage area. For example, in the coverage area, the CPICH of the femtocell service area<i>E</i>_<i>c</i><i>/Io</i>Should be better than<i>Q</i>_{<i>qualmin, femto</i>}。

<i>P</i>_femto,temp1=<i>PL</i>_Edge,NL+<i>Io</i>_macro,NLM+<i>X</i>

Parameter X is based on: assuming coverage in femtocell service area<i>PL</i>_edge,NLThe minimum expected downlink CPICH experienced by HUE (femtocell service area) with a certain load at the edge <i>Ec/Io</i>; The ratio of the pilot frequency energy per chip to the total transmit power spectral density (ie, CPICH <i>Ec/Ior</i>); and load function.

Calculate the parameters by measuring the CPICH RSCP of the intra-frequency macro cell service area (or the co-located macro cell service area discussed in this case) by using NLM<i>Io</i>_macro,NLM. If the macro cell service area is not detected, you can set the parameter<i>Io</i>_macro,NLMSet to N₀。

Adjacent channels (other service providers) protection conditions:

In order to limit the interference caused to adjacent channels belonging to another wireless network service provider, additional requirements for output power are provided in section 6.4.6 of 3GPP TS 25.104. Generally, this requirement is based on a comparison of CPICH Ec and Io. Taking into account the adjacent channel protection conditions specified by these requirements, the parameters<i>P</i>_{<i>femto,temp</i>}₂Defined as the total transmit power.

Adjacent channels (same service provider) protection conditions:

In order to limit the interference caused to adjacent channel macro cell service areas belonging to the same service provider (for example, a service provider of a femtocell service area), additional requirements for output power are provided below.

If the conditions of the same service provider in adjacent channels are valid:

CPICH <i>RSCP</i>_{adjacentchannel}[dBm] is the main CPICH (strongest PSC) coding power on the adjacent channel measured by the NLM at the femtocell service area. (If transmit diversity is applied on the primary CPICH, the CPICH Ec should be the sum of the coding power of the primary CPICH transmitted from each antenna [W].)

The total transmit power limit is provided below:

like<i>RSCP</i>_{adjacentchannel}-105d Bm

<i>P</i>_<i>a</i>_{<i>djacentchannel</i>}_,sameop=<i>PL</i>_{protection,adjchan}+<i>ACIR</i>+<i>RSSI</i>_{<i>adjacentchannel</i>}+<i>I</i>_{0,thisfemto,contrib}-10<i>log</i>10(<i>LF</i>_femto)[dBm]

otherwise

<i>P</i>_{<i>adjacentchannel</i>}_,sameop=<i>P</i>_femto,max

end

Otherwise (if)

<i>P</i>_{<i>adjacentchannel</i>}_,sameop=<i>P</i>_femto,max

End (if)

<i>P</i>_femto,min[dBm]: The minimum allowable value of the total femto cell service area transmit power

<i>P</i>_femto,max[dBm]: The maximum allowable value of the total femto cell service area transmit power

Taking into account the protection conditions of adjacent channels, make<i>P</i>_{<i>femto,temp</i>}₃=<i>P</i>_{<i>adjacentchannel</i>}_,sameopIs the total transmit power.

The transmit power of the femtocell service area is selected as the minimum of the three criteria.

<i>P</i>_{<i>femto,NL</i>}=max[min(<i>P</i>_{<i>femto,temp</i>}₁,<i>P</i>_{<i>femto,temp</i>}₂,<i>P</i>_{<i>femto,temp</i>}₃,<i>P</i>_{<i>femto,max</i>}),<i>P</i>_{<i>femto,min</i>}]。

The above procedure is performed at each femtocell service area in the unit (e.g., building). Assume that there are<i>n</i>Femtocell service area, then<i>：</i>

<i>P</i>_{<i>femto,NL</i>}=[<i>P</i>_{<i>femto,NL,</i>}₁,<i>P</i>_{<i>femto,NL,</i>}₂,...,<i>P</i>_{<i>femto,NL,n</i>}]。

The algorithm (or the skilled person) selects the maximum value among the calculated transmit power levels:

<i>P</i>_<i>init</i>=max(<b><i>P</i></b>_{<i>femto,NL</i>})。

Then, initialize the transmit power of the femtocell service area to the same power<i>P</i>_<i>init</i>. therefore,

<i>P</i>_{<i>femto,inuxe</i>}=<i>P</i>_<i>init</i>

This ensures that all femtocell service areas transmit at a power high enough to ensure initial coverage; the handover boundary between two femtocell service areas is located at an equal path loss from each femtocell service area; And try to ensure (after the power adjustment step assisted by the craftsman) that the mismatch between the final powers is low. The next step is the power adjustment assisted by the artisan.

<b>Artisan-assisted power adjustment</b>

The artisan initiates voice dialing and walks around the unit. The following suggestions apply to the walking route taken by the artisan: The artisan should walk across the unit comprehensively and evenly in order to report measurements from all areas that need to be covered. It is recommended that artisans walk slowly along the entire artisan walking route. It is possible to perform multiple walks on the skilled person's walking route to obtain more measurement reports (for example, to reduce estimation errors caused by channel fading).

The femtocell service area collects reports from the mobile station of the skilled person and uses these reports. The femtocell service area ranks the highest CPICH among these reports <i>Ec/Io</i>. Due to the equal transmit power value and 0 dB hysteresis + CIO, measurement report messages (MRMs) will be sent to the nearest femto (for example, minimum path loss). For each measurement report message received, the femtocell service area extracts the PL and the macrocell service area RSSI. In addition, the femtocell service area calculates the transmit power value as follows: For each measurement report message received (<i>i</i>), to meet the coverage conditions. The coverage condition is calculated in a manner similar to the coverage condition for the transmission power initialization described above, except that the information is obtained from the measurement report. For example, for each measurement report message received (<i>i</i>), based on path loss,<i>Io</i>_macro,tech,iAnd X to calculate the parameters<i>P</i>_femto,tech,i; Where the parameters<i>Io</i>_macro,tech,iIt is calculated using the CPICH RSCP of the intra-frequency macro cell service area (or the co-located macro cell service area discussed in this case) measured by the access terminal. If the macro cell service area is not detected, you can set the parameter<i>Io</i>_macro,tech,iSet to N₀。

Assuming that it is collected at the femtocell service area<i>m</i>Reports, then:

<i>P</i>_{<i>femto,tech</i>}=[<i>P</i>_{<i>femto,tech,</i>}₁,<i>P</i>_<i>femto</i>_,_<i>tech</i>_,2,...,<i>P</i>_<i>femto</i>_,_<i>tech</i>_,_<i>m</i>]

Femtocell service area selects percent<i>covTxper</i>And initialize the downlink transmit power level of the femtocell service area to the same power. that is:

<i>P</i>_<i>SMART</i>=max[min(percentile(<i>P</i>_{<i>femto,tech</i>},<i>covTxper</i>),<i>P</i>_{<i>femto,temp</i>}₂,<i>P</i>_{<i>femto,temp</i>}₃,<i>P</i>_{<i>femto,max</i>}),<i>P</i>_{<i>femto,min</i>}]。

Here, the function percentile calculates<i>P</i>_{<i>femto,tech</i>}Middle percent<i>covTxper</i>The value of; and<i>P</i>_{<i>femto,temp</i>}₂and<i>P</i>_{<i>femto,temp</i>}₃It is obtained by calculating the total output power taking into account the protection requirements of adjacent channels of the same and other service providers.

After completing the SMART procedure, the Femtocell service area began to use the naming<i>For P</i>_<i>SMART</i>The total transmit power is transmitted on the downlink. therefore,

<i>P</i>_{<i>femto,inuse</i>}=<i>P</i>_<i>SMART</i>

The skilled person can execute the SMART program multiple times to fine-tune the transmit power of the femtocell service area.

FIG. 9 illustrates several exemplary components (represented by corresponding blocks), which may be incorporated into, for example, an access terminal 902, an access point 904, and a network entity 906 (e.g., corresponding to the access point of FIG. 1, respectively). Nodes such as the terminal 102, the access point 104, and the network entity 112) perform the operations related to the transmission power control taught in this case. The described components can also be incorporated into other nodes in the communication system. For example, other nodes in the system may include components similar to those described for one or more of the access terminal 902, the access point 904, or the network entity 906 to provide similar functions. In addition, a given node may include one or more of the above-mentioned components. For example, an access point may include multiple transceiver components that enable the access point to operate on multiple carriers and/or communicate via different technologies.

As shown in FIG. 9, each of the access terminal 902 and the access point 904 includes one or more wireless transceivers (represented by the transceiver 908 and the transceiver 910, respectively) for communicating with other nodes. Each transceiver 908 includes a transmitter 912 for sending signals (for example, messages, measurement reports, instructions, other types of information, etc.) and for receiving signals (for example, messages, FL signals, pilot signals, Handover parameters, other types of information, etc.) receiver 914. Similarly, each transceiver 910 includes a transmitter 916 for sending signals (for example, messages, requests, instructions, FL signals, pilot signals, handover parameters, other types of information, etc.) and for receiving signals (For example, messages, measurement reports, transmit power values, other types of information, etc.) receiver 918.

Each of the access point 904 and the network entity 906 includes one or more network interfaces (respectively composed of the network interface 920 and the network interface 922) for communicating with other nodes (for example, other network entities). Express). For example, the network interfaces 920 and 922 may be configured to communicate with one or more network entities via a wired backhaul or backbone network or a wireless backload or backbone network. In some aspects, the network interfaces 920 and 922 may be implemented as transceivers (for example, including a transmitter component and a receiver component), and the transceiver is configured to support wired communication or wireless communication (for example, sending and receiving: message , Measurement reports, instructions, handover parameters, transmit power values, other types of information, etc.). Accordingly, in the example of FIG. 9, the network interface 920 is illustrated as including a transmitter 924 for transmitting signals and a receiver 926 for receiving signals. Similarly, the network interface 922 is illustrated as including a transmitter 928 for transmitting signals and a receiver 930 for receiving signals.

The access terminal 902, the access point 904, and the network entity 906 also include other components that can be used to support the power control-related operations taught in this case. For example, the access terminal 902 includes a processing system 932, which is used to provide functions related to controlling the transmission power (for example, providing measurement report information, identifying reconfiguration trigger conditions, and generating a reconfiguration of the femtocell service area). Indicates that it is determined that the measurement report is not being received, and the measurement report is determined to be received), and the processor system 932 is also used to provide other processing functions. Similarly, the access point 904 includes a processor system 934 for providing functions related to controlling the transmission power (for example, controlling the transmission power, defining a first handover lag value, and defining a second handover lag value, Determine at least one transmit power value, configure at least one femto cell service area, provide measurement report information, identify the reconfiguration trigger condition, generate an instruction to reconfigure the femto cell service area, determine whether the measurement report is not being received, and determine that it is receiving The measurement report, based on the measurement report received from the second macro cell service area, controls the transmit power of the femto cell service area on the first frequency, determines the first transmit power level, and determines the second transmit power level, Determine the third transmit power level, select the smallest transmit power level from the first transmit power level, the second transmit power level, and the third transmit power level, and control the transmit power of the femtocell service area), and The processing system 934 is also used to provide other processing functions. In addition, the network entity 906 includes a processing system 936 for providing functions related to controlling the transmission power (for example, as described above for the processing system 934), and the processing system 936 is also used for providing other functions. Processing function. The access terminal 902, the access point 904, and the network entity 906 respectively include memory components 938, 940, and 942 (e.g., each of them) for storing information (e.g., measurement report information, thresholds, parameters, etc.). One includes memory devices). In addition, the access terminal 902, the access point 904, and the network entity 906 respectively include user interface devices 942, 944, and 946. The user interface devices 942, 944, and 946 are used to provide instructions to the user (for example, auditory Instructions and/or visual instructions), and/or used to receive user input (for example, after the user activates a sensing device such as a keypad, touch screen, microphone, etc.).

For convenience, in FIG. 9, the access terminal 902 and the access point 904 are illustrated as including components that can be used in the various examples described in this case. In practice, the blocks shown may have different functions in different implementations. For example, in an implementation using different wireless communication technologies, the processor systems 932, 934, and 936 will be configured to support different operations.

The components of Figure 9 can be implemented in various ways. In some implementations, the components of FIG. 9 may be implemented in one or more circuits such as one or more processors and/or one or more ASICs (which may include one or more processors). In this case, each circuit (for example, a processor) can use and/or incorporate a data memory for storing information or executable code used by the circuit to provide this function. For example, the one or more processors of the access terminal and the data memory of the access terminal (e.g., by executing appropriate codes and/or by appropriately configuring processor components) may be used to implement what is represented by block 908 Some of the functions and some or all of the functions represented by blocks 932, 938, and 942. Similarly, the representation represented by block 910 can be realized by one or more processors of the access point and the data memory of the access point (for example, by executing appropriate code and/or by appropriately configuring processor components) Some of the functions of and some or all of the functions represented by blocks 920, 934, 940, and 944. In addition, the blocks 922, 936 may be implemented by one or more processors of the network entity and the data memory of the network entity (for example, by executing appropriate codes and/or by appropriately configuring processor components). Some or all of the functions indicated by, 942 and 946.

As discussed above, in some aspects, the teachings of this case can be used to include macro-scale coverage (for example, large-area cellular networks such as 3G networks, commonly referred to as macro networks or WANs) and Smaller-scale coverage (for example, a residence-based or building-based network environment, usually referred to as a LAN) network. When an access terminal (AT) moves through such a network, the access terminal can be served by an access point that provides macro coverage in some locations, while the access terminal can be provided with a smaller scale coverage in other locations. Access point service. In some aspects, nodes with smaller coverage can be used to provide progressive capacity growth, in-building coverage, and different services (for example, for a more robust user experience).

In the description of this case, a node that provides coverage on a relatively large area (for example, an access point) may be called a macro access point, while a node that provides coverage on a relatively small area (for example, a residence) It can be called a femto access point. It should be recognized that the teachings of this case can be applied to nodes associated with other types of coverage areas. For example, a pico access point may provide coverage over an area smaller than a macro area and larger than a femto area (e.g., coverage in a commercial building). In various applications, other terms can be used to refer to macro access points, femto access points, or other access point type nodes. For example, a macro access point can be configured or referred to as an access node, base station, access point, eNodeB, macro cell service area, and so on. In addition, the femto access point can be configured or referred to as a home node B, a home eNodeB, an access point base station, a femto cell service area, and so on. In some implementations, a node may be associated with one or more cell service areas or sectors (e.g., referred to or divided into one or more cell service areas or sectors). Cell service areas or sectors associated with a macro access point, a femto access point, or a pico access point may be referred to as a macro cell service area, a femto cell service area, or a pico cell service area, respectively.

FIG. 10 illustrates a wireless communication system 1000 configured to support multiple users, in which the teaching of this case can be implemented. The system 1000 provides communication for multiple cell service areas 1002 such as macro cell service areas 1002A-1002G, where each cell service area is served by a corresponding access point 1004 (for example, access point 1004A-1004G). As shown in FIG. 10, the access terminals 1006 (for example, the access terminals 1006A-1006L) can be dispersed in various locations of the entire system over time. For example, each access terminal 1006 can interact with one or more on the forward link (FL) and/or reverse link (RL) at a given moment according to whether the access terminal 1006 is valid and whether it is in soft handover. 1004 access points for communication. The wireless communication system 1000 can provide services over a larger geographic area. For example, the macro cell service area 1002A-1002G may cover several neighboring blocks or several miles in a rural environment.

FIG. 11 illustrates an exemplary communication system 1100 in which one or more femto access points are deployed in a network environment. Specifically, the system 1100 includes multiple femto access points 1110 (e.g., femto access points 1110A and 1110B). Each femto access point 1110 can be coupled to a wide area network 1140 (for example, the Internet) and a mobile service provider core network 1150 via a DSL router, cable modulator, wireless link, or other connection means (not shown) . As will be discussed below, each femto access point 1110 may be configured to serve the associated access terminal 1120 (e.g., access terminal 1120A), and optionally, serve others (e.g., hybrid or alien Of) access terminal 1120 (for example, access terminal 1120B). In other words, access to the femto access point 1110 can be restricted, so that a given access terminal 1120 can be served by a set of designated (for example, home) femto access points 1110, but not by any unspecified access point 1110. Femto access points 1110 (e.g., neighboring femto access points 1110) serve.

12 illustrates an example of a coverage map 1200 in which several tracking areas 1202 (or routing areas or location areas) are defined, wherein each tracking area 1202 includes several macro coverage areas 1204. Here, the coverage areas associated with the tracking areas 1202A, 1202B, and 1202C are drawn with thick lines, and the macro coverage area 1204 is represented by a larger hexagon. The tracking area 1202 also includes a femto coverage area 1206. In this example, each of the femto coverage areas 1206 (e.g., femto coverage areas 1206B and 1206C) is illustrated as one or more macro coverage areas 1204 (e.g., macro coverage areas 1204A and 1204B) middle. However, it should be appreciated that some or all of the femto coverage area 1206 may not be located in the macro coverage area 1204. In practice, a large number of femto coverage areas 1206 (e.g., femto coverage areas 1206A and 1206D) can be defined within a given tracking area 1202 or macro coverage area 1204. In addition, one or more pico coverage areas (not shown) may be defined in a given tracking area 1202 or macro coverage area 1204.

Referring again to FIG. 11, the owner of the femto access point 1110 can subscribe to mobile services provided via the mobile service provider core network 1150, such as 3G mobile services. In addition, the access terminal 1120 can operate in both a macro environment and a smaller-scale (for example, residential) network environment. In other words, according to the current location of the access terminal 1120, the macro cell service area access point 1160 associated with the mobile service provider core network 1150 or a group of femto access points 1110 (e.g., located in Any one of the femto access points 1110A and 1110B) in the corresponding user residence 1130 serves the access terminal 1120. For example, when the user is not at home, the standard macro access point (e.g., access point 1160) can serve him, and when the user is at home, the femto access point (e.g., access point 1110A) can serve him He serves. Here, the femto access point 1110 can be backward compatible with the conventional access terminal 1120.

Femto access points 1110 may be deployed on a single frequency or, alternatively, on multiple frequencies. Depending on the specific configuration, the single frequency or one or more of the multiple frequencies may overlap with one or more frequencies used by the macro access point (e.g., access point 1160).

In some aspects, the access terminal 1120 can be configured to connect to a preferred femto access point (e.g., the home femto access point of the access terminal 1120) whenever it can connect to the preferred femto access point. Femto access point. For example, whenever the access terminal 1120A is located in the user's residence 1130, it can be expected that the access terminal 1120A only communicates with the home femto access point 1110A or 1110B.

In some aspects, if the access terminal 1120 is operating in the macro cellular network 1150 but is not located on its best network (for example, as defined in the better roaming list), the access terminal 1120 can Use a better system reselection (BSR) procedure to continue searching for the best network (for example, a better femto access point 1110), which can involve periodic scanning of available systems to determine a better system Whether it is currently available, and then obtain such a better system. The access terminal 1120 can restrict the search for specific frequency bands and channels. For example, one or more femto channels can be defined so that all femto access points (or all restricted femto access points) in an area operate on the femto channel. The search for the best system can be repeated periodically. After exploring a better femto access point 1110, the access terminal 1120 selects the femto access point 1110 and logs on it for use when it is located within the coverage area of the femto access point 1110.

Access to femto access points may be restricted in some ways. For example, a given femto access point may only provide certain services for certain access terminals. In deployments with so-called restricted (or closed) access, a set of femto access points (for example, a set of femto access points located in the corresponding user residence 1130) may only be defined by the macro cell service area mobile network. The pico access point 1110) serves a given access terminal. In some implementations, the access point may be restricted to not provide at least one of the following for at least one node (such as an access terminal): signal transmission, data access, login, paging, or service.

In some aspects, a restricted femto access point (also referred to as a closed user group home node B) is a femto access point that provides services to a specified group of restricted access terminals. The set of access terminals can be temporarily or permanently extended as needed. In some aspects, a closed user group (CSG) can be defined as a group of access points (for example, femto access points) that share a common access control list of an access terminal.

Therefore, various relationships may exist between a given femto access point and a given access terminal. For example, from the perspective of an access terminal, an open femto access point may refer to a femto access point with unrestricted access (for example, the femto access point allows access by any access terminal). A restricted femto access point may refer to a femto access point that is restricted in some way (e.g., restricted in access and/or login). A home femto access point may refer to a femto access point on which an access terminal is authorized to access and operate (for example, to provide permanent access to a defined set of one or more access terminals). Hybrid (or guest) femto access points can point to different access terminals to provide different levels of service (for example, some access terminals can be allowed partial and/or temporary access while other access terminals can be allowed full access )S femto access point. A foreign femto access point may refer to a femto access point that the access terminal is not authorized to access or operate on except for possible emergency situations (for example, 911 dialing).

From the perspective of a restricted femto access point, a home access terminal can refer to an access terminal authorized to access the restricted femto access point installed in the residence of the owner of the access terminal (usually, home The access terminal can permanently access the femto access point). A guest access terminal can refer to an access terminal that can temporarily access restricted femto access points (for example, it is restricted based on deadlines, usage time, bytes, number of connections, or some other criteria) . An external access terminal may refer to an access terminal that does not have permission to access the restricted femto access point (for example, does not have the identity to log in to the restricted femto access point) except for possible emergencies (e.g., 911 dialing). Code or permitted access terminal).

For convenience, the content disclosed in this case describes various functions with femto access points as the background. However, it should be recognized that pico access points can provide the same or similar functions for a larger coverage area. For example, pico access points can be restricted, home pico access points can be defined for a given access terminal, and so on.

The teachings of this case can be used in the wireless multiple access communication system. The wireless multiple access communication system supports the communication of multiple wireless multiple access terminals at the same time. Here, each terminal can communicate with one or more access points via transmissions on the forward and reverse links. The forward link (or downlink) refers to the communication link from the access point to the terminal, and the reverse link (or uplink) refers to the communication link from the terminal to the access point. The communication link can be established via a single input single output system, a multiple input multiple output (MIMO) system, or some other type of system.

The MIMO system uses multiple (<i>N</i>_<i>T</i>Each) transmitting antenna and multiple (<i>N</i>_<i>R</i>A) receiving antenna for data transmission. Depend on<i>N</i>_<i>T</i>Transmitting antennas and<i>N</i>_<i>R</i>The MIMO channel formed by two receiving antennas can be decomposed into<i>N</i>_<i>S</i>Independent channels, which are also called spatial channels, where<i>N</i>_<i>S</i><img file="TW201216748A_D0013.tif" />min{<i>N</i>_<i>T</i>,<i>N</i>_<i>R</i>}。<i>N</i>_<i>S</i>Each of the independent channels corresponds to a dimension. If the additional dimensions established by multiple transmit and receive antennas are utilized, the MIMO system can provide improved performance (for example, higher transmission volume and/or higher reliability).

The MIMO system can support Time Division Duplex (TDD) and Frequency Division Duplex (FDD). In the TDD system, the forward link transmission and the reverse link transmission are performed in the same frequency domain, so the mutual principle allows the forward link channel to be estimated based on the reverse link channel. This allows the access point to extract transmit beamforming gain on the forward link when multiple antennas are available at the access point.

FIG. 13 illustrates a wireless device 1310 (e.g., an access point) and a wireless device 1350 (e.g., an access terminal) of an exemplary MIMO system 1300. At the device 1310, the data source 1312 can provide the transmission (TX) data processor 1314 with traffic data of multiple data streams. Subsequently, each data stream can be sent on the corresponding antenna.

The TX data processor 1314 formats, encodes, and interleaves the traffic data of each data stream based on the specific encoding scheme selected for each data stream to provide encoded data. The coded data and pilot frequency data of each data stream can be multiplexed using OFDM technology. In general, the pilot frequency data is a known data model processed in a known manner, and the pilot frequency data can be used at the receiver system to estimate the channel response. Then, based on the specific modulation scheme selected for each data stream (for example, BPSK, QPSK, M-PSK or M-QAM, etc.), the multiplexed pilot frequency and coded data of the data stream are modulated (I.e., symbol mapping) to provide modulation symbols. The data rate, coding, and modulation of each data stream can be determined by instructions executed by the processor 1330. The data memory 1332 can store program codes, data, and other information used by the processor 1330 or other components of the device 1310.

Subsequently, the modulation symbols of all data streams can be provided to the TX MIMO processor 1320, and the TX MIMO processor 1320 can further process the modulation symbols (for example, for OFDM). Subsequently, the TX MIMO processor 1320 gave<i>N</i>_<i>T</i>Two transceivers (XCVR) 1322A to 1322T provide<i>N</i>_<i>T</i>A stream of modulation symbols. In some aspects, the TX MIMO processor 1320 applies beamforming weights to the symbols of the data stream and the antenna that is transmitting the symbol.

Each transceiver 1322 receives and processes the corresponding symbol stream in order to provide one or more analog signals, and further adjusts (for example, amplifies, filters, and up-converts, etc.) these analog signals to provide suitable for MIMO channels The transmitted modulated signal. Subsequently, from<i>N</i>_<i>T</i>The antennas 1324A to 1324T transmit from the transceivers 1322A to 1322T<i>N</i>_<i>T</i>A modulation signal.

At device 1350, by<i>N</i>_<i>R</i>The two antennas 1352A to 1352R receive the transmitted modulated signal, and the signal received from each antenna 1352 is provided to the respective transceiver (XCVR) 1354A to 1354R. Each transceiver 1354 adjusts (for example, filtering, amplifying, and down-converting, etc.) the received signal, digitizing the adjusted signal to provide samples, and further processing the samples to provide the corresponding "received" Symbol streaming.

Subsequently, the receiving (RX) data processor 1360 can download from<i>N</i>_<i>R</i>Transceiver 1354 to receive<i>N</i>_<i>R</i>Received symbol streams and process the received symbol streams based on specific receiver processing technology to provide<i>N</i>_<i>T</i>A stream of "detected" symbols. Subsequently, the RX data processor 1360 demodulates, deinterleaves and decodes each detected symbol stream to recover the traffic data of the data stream. The processing performed by the RX data processor 1360 is complementary to the processing performed by the TX MIMO processor 1320 and the TX data processor 1314 at the device 1310.

The processor 1370 periodically decides which precoding matrix to use (as discussed below). The processor 1370 formulates a reverse link message including a matrix index part and a rank value part. The data memory 1372 can store program codes, data, and other information used by the processor 1370 or other components of the device 1350.

The reverse link message may include various types of information about the communication link and/or the received data stream. Subsequently, the reverse link message can be processed by the TX data processor 1338, modulated by the modulator 1380, adjusted by the transceivers 1354A to 1354R, and sent back to the device 1310, where the TX data processor 1338 is also from the data source 1336 receives traffic data from multiple data streams.

At the device 1310, the modulated signal from the device 1350 is received by the antenna 1324, adjusted by the transceiver 1322, demodulated by the demodulator (DEMOD) 1340, and processed by the RX data processor 1342 to extract the Reverse link message sent by device 1350. Subsequently, the processor 1330 decides which precoding matrix to use to determine the beamforming weights, and then processes the extracted information.

FIG. 13 also illustrates that the communication components may include one or more components that perform the transmission power control operations taught in this case. For example, as taught in this case, the transmit power control component 1390 may coordinate with the processor 1330 and/or other components of the device 1310 to control transmission for the device 1310 (eg, to another device such as the device 1350). Transmission) and/or the transmission power of at least one other device. In addition, as taught in this case, the transmission power control component 1392 may coordinate with the processor 1370 and/or other components of the device 1350 to assist transmission power control operations (for example, for transmission of the device 1310 and/or other devices). It should be appreciated that for each device 1310 and 1350, a single component may provide the functions of two or more of the described components. For example, a single processing component may provide the functions of the transmit power control component 1390 and the processor 1330. Similarly, a single processing component can provide the functions of the transmit power control component 1392 and the processor 1370.

The teachings of this case can be incorporated into various types of communication systems and/or system components. In some aspects, the teachings of this case can be used to support communication with multiple users by sharing available system resources (for example, by specifying one or more of bandwidth, transmit power, encoding, interleaving, etc.) In the multiple access system. For example, the teachings of this case can be applied to any one or combination of the following technologies: code division multiple access (CDMA) system, multi-carrier CDMA (MCCDMA), broadband CDMA (W-CDMA), high-speed packet access (HSPA, HSPA+) ) System, time division multiple access (TDMA) system, frequency division multiple access (FDMA) system, single carrier FDMA (SC-FDMA) system, orthogonal frequency division multiple access (OFDMA) system or other multiple Industrial access technology. The wireless communication system adopting the teachings of this case can be designed to implement one or more standards, for example, IS-95, cdma2000, IS-856, W-CDMA, TDSCDMA and other standards. CDMA networks can implement radio technologies such as Universal Terrestrial Radio Access (UTRA), cdma2000, or some other technology. UTRA includes W-CDMA and low chip rate (LCR). cdma2000 technology covers IS-2000, IS-95 and IS-856 standards. TDMA networks can implement radio technologies such as the Global System for Mobile Communications (GSM). OFDMA network can realize such as evolved UTRA (E-UTRA), IEEE 802.11, IEEE 802.16, IEEE802.20, Flash-OFDM<img file="TW201216748A_D0014.tif" />And so on and so on radio technology. UTRA, E-UTRA and GSM are part of the Universal Mobile Telecommunications System (UMTS). The teachings of this case can be implemented in the 3GPP Long Term Evolution (LTE) system, Ultra Mobile Broadband (UMB) system and other types of systems. LTE is a release version of UMTS that uses E-UTRA. UTRA, E-UTRA, GSM, UMTS and LTE are described in documents from an organization named "3rd Generation Partnership Project" (3GPP), and in documents from an organization named "3rd Generation Partnership Project 2" Cdma2000 is described in documents of the organization (3GPP2). Although some aspects of the disclosure of this case can be described in 3GPP terms, it should be understood that the teachings of this case can be applied to 3GPP (e.g., Rel99, Rel5, Rel6, Rel7) technologies and 3GPP2 (e.g., 1xRTT, 1xEV-DO Re10). , RevA, RevB) technology and other technologies.

The teachings of this case can be incorporated into a variety of devices (e.g., nodes) (e.g., implemented in or executed by multiple devices). In some aspects, a node (for example, a wireless node) implemented according to the teachings of the present application may include an access point or an access terminal.

For example, the access terminal may include, implemented or known as user equipment, user station, user unit, mobile station, mobile station, mobile node, remote station, remote terminal, user terminal, user agent, userBydevice or some other term. In some implementations, the access terminal may include cellular phones, wireless phones, communication period initiation protocol (SIP) phones, wireless zone loop (WLL) stations, personal digital assistants (PDAs), handheld devices with wireless connection capabilities, Some other appropriate processing device connected to the wireless modem. Accordingly, one or more aspects taught in this case can be incorporated into phones (e.g., cellular phones or smart phones), computers (e.g., laptop computers), portable communication devices, portable computing devices ( For example, personal data assistants), entertainment equipment (e.g., music equipment, video equipment, or satellite radio stations), global positioning system equipment, or any other suitable equipment configured to communicate via wireless media.

The access point may include, implemented or known as Node B, eNodeB, Radio Network Controller (RNC), Base Station (BS), Radio Base Station (RBS), Base Station Controller (BSC), Base Station Transceiver Station (BTS), Transceiver Function (TF), Radio Transceiver, Radio Router, Basic Service Set (BSS), Extended Service Set (ESS), Macro Cell Service Area, Macro Node, Home eNB (HeNB), Milli Pico cell service area, femto node, pico node, or some other similar term.

In some aspects, nodes (e.g., access points) may include access points for communication systems. For example, such an access node may provide a connection to or to a network (for example, a wide area network such as the Internet, or a cellular network) via a wired or wireless communication link to the network. Correspondingly, the access node can enable another node (for example, an access terminal) to access the network or implement some other function. In addition, it should be recognized that one or both of the aforementioned nodes may be portable or, in some cases, relatively inportable.

In addition, it should be recognized that wireless nodes can send and/or receive information in a non-wireless manner (e.g., via a wired connection). Therefore, the receivers and transmitters discussed in this case may include appropriate communication interface components (for example, electrical or optical interface components) to communicate via non-wireless media.

The wireless nodes can communicate via one or more wireless communication links based on or otherwise supporting any suitable wireless communication technology. For example, in some aspects, wireless nodes can be associated with the network. In some aspects, the network may include a local area network or a wide area network. The wireless device may support or otherwise use one or more of various wireless communication technologies, protocols, or standards (for example, CDMA, TDMA, OFDM, OFDMA, WiMAX, Wi-Fi, etc.) as discussed in this case. Similarly, a wireless node may support or otherwise use one or more of various corresponding modulation or multiplexing schemes. Therefore, the wireless node may include appropriate components (for example, an air interface) to establish one or more wireless communication links using the above or other wireless communication technologies, and communicate via the one or more wireless communication links. For example, a wireless node may include a wireless transceiver with associated transmitter and receiver components. The associated transmitter and receiver components may include various components that facilitate communication over wireless media (e.g., signal generators). And signal processor).

The functions described in this case (for example, with respect to one or more figures in the drawings) may in some aspects correspond to the functions of "members for" similarly designated in the scope of the appended patent application. Referring to Figures 14, 15, 16, and 17, the devices 1400, 1500, 1600, and 1700 are illustrated as a series of functional modules related to each other. Here, for example, the module 1402 for receiving measurement reports can correspond to the receiver discussed in this case in at least some aspects. For example, the module 1404 for controlling the transmission power may correspond to the processing system discussed in this case in at least some aspects. For example, the module 1406 for defining the handover lag value can correspond to the processing system discussed in this case at least in some aspects. For example, the module 1408 for receiving the transmission power value can correspond to the receiver discussed in this case at least in some aspects. For example, the module 1410 for determining at least one transmission power value can correspond to the processing system discussed in this case at least in some aspects. For example, the module 1412 for configuring at least one femtocell service area may correspond to the processing system discussed in this case at least in some aspects. For example, the module 1414 for providing measurement report information can correspond to the processing system discussed in this case in at least some aspects. For example, the module 1502 for receiving information can correspond to the receiver discussed in this case in at least some aspects. For example, the module 1504 for identifying trigger conditions for reconfiguration can correspond to the processing system discussed in this case at least in some aspects. For example, the module 1506 for generating an instruction to reconfigure the femtocell service area may correspond to the processing system discussed in this case at least in some aspects. For example, the module 1602 for determining that the measurement report is not being received from the first macro cell service area can correspond to the processing system discussed in this case in at least some aspects. For example, the module 1604 for determining that the measurement report is being received from the second macro cell service area may correspond to the processing system discussed in this case in at least some aspects. For example, the module 1606 for controlling the transmit power of the femtocell service area may correspond to the processing system discussed in this case at least in some aspects. For example, the module 1702 for determining the first transmit power level can correspond to the processing system discussed in this case at least in some aspects. For example, the module 1704 for determining the second transmit power level can correspond to the processing system discussed in this case at least in some aspects. For example, the module 1706 for determining the third transmit power level can correspond to the processing system discussed in this case at least in some aspects. For example, to select The module 1708 of the minimum transmit power level can correspond to the processing system discussed in this case in at least some aspects. For example, the module 1710 for controlling the transmit power of the femtocell service area may correspond to the processing system discussed in this case at least in some aspects.

The functions of the modules of Figs. 14, 15, 16 and 17 can be realized in various ways consistent with the teaching of this case. In some aspects, the functions of the modules can be implemented as one or more electronic components. In some aspects, the functions of the blocks can be implemented as a processing system including one or more processor components. In some aspects, for example, at least a part of one or more integrated circuits (for example, ASIC) can be used to realize the functions of the modules. As discussed in this case, the integrated circuit may include a processor, software, other related components, or some combination of the foregoing. It is also possible to implement the functions of these modules in some other way taught in this case. In some aspects, one or more of the virtual squares in any of the virtual squares in FIGS. 14, 15, 16, and 17 are optional.

It should be understood that any reference to elements using names such as "first", "second", etc. in this case generally does not limit the quantity or order of these elements. On the contrary, this case uses these names as a convenient way to distinguish two or more elements or instances of elements. Therefore, the reference to the first element and the second element does not mean that only two elements can be used or that the first element must precede the second element in some way. In addition, unless otherwise stated, a set of elements may include one or more elements. In addition, the following terms used in the specification or the scope of the patent application mean "A or B or C or any combination of these elements": "at least one of A, B or C" or "A, B or C" One or more of" or "at least one of the group consisting of A, B, and C".

Those skilled in the art should understand that information and signals can be represented using any of a variety of different techniques and methods. For example, the data, instructions, commands, information, signals, bits, symbols, and chips mentioned throughout the above description can use voltage, current, electromagnetic waves, magnetic fields or magnetic particles, light fields or light particles, or any combination thereof To represent.

Those skilled in the art should also understand that the illustrative logic blocks, modules, processors, components, circuits, and algorithm steps described in conjunction with the aspects disclosed in this case can all be implemented as electronic hardware (for example, Digital implementation, analog implementation, or a combination of the two designed using source code or some other technology), various forms of combined instruction program or design code (for convenience, this may be referred to as "software" or "software" Module"), or a combination of the two. In order to clearly illustrate this interchangeability between hardware and software, each illustrative component, block, module, circuit, and step is described above as a whole around its function. As for whether this function is implemented as hardware or software, it depends on the specific application and the design constraints imposed on the entire system. Those skilled in the art can implement the described functions in a flexible manner for each specific application, but such implementation decisions should not be interpreted as departing from the scope of protection disclosed in this case.

The illustrative logic blocks, modules, and circuits described in combination with the aspect disclosed in this case can all be implemented in an integrated circuit (IC), an access terminal or an access point, or by an integrated circuit (IC), a memory Take the terminal or access point to achieve. ICs may include general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices designed to perform the functions described in this case, Individual gates or transistor logic devices, individual hardware components, electronic components, optical components, mechanical components or any combination of the above, and the IC can execute codes or instructions located inside the IC, outside the IC, or inside and outside the IC. The general-purpose processor may be a microprocessor, or, the processor may also be any general processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, a plurality of microprocessors, a combination of one or more microprocessors and a DSP core, or any other such structure.

It should be understood that the specific order or hierarchy of steps in the disclosed process is an example of an exemplary method. It should be understood that, based on design preferences, the specific order or level of the steps in these processes can be rearranged and remain within the scope of the disclosure of this case. The attached method claims provide elements of each step in an exemplary order, and are not intended to be limited to the specific order or hierarchy provided.

In one or more exemplary embodiments, the described functions may be implemented in hardware, software, firmware, or any combination of the foregoing. If implemented in software, these functions can be stored or sent on a computer readable medium as one or more instructions or codes. Computer readable media include computer storage media and communication media. Communication media includes any media that facilitates the transfer of computer programs from one place to another. The storage medium can be any available medium that the computer can access. By way of example and not limitation, such computer-readable media can include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or can be used to carry or store Any other medium that can be accessed by a computer in the desired program code in the form of instructions or data structures. In addition, any connection can be appropriately referred to as a computer-readable medium. For example, if the software is sent from a website, server, or other remote source using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave The coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of the media. The disks and discs used in this case include compact discs (CD), laser discs, optical discs, digital versatile discs (DVD), floppy discs and Blu-ray discs, among which the discs are usually reproduced magnetically Data, and optical discs use lasers to reproduce data in an optical manner. Therefore, in some aspects, computer-readable media may include non-transitory computer-readable media (e.g., tangible media). In addition, in some aspects, computer-readable media may include temporary computer-readable media (eg, signals). The above combination should also be included in the scope of computer readable media. It should be recognized that the computer-readable medium can be implemented in any suitable computer program product.

The term "decision" used in this case covers many actions. For example, "decision" can include calculation, calculation, processing, derivation, research, inspection (for example, looking up a table, database or other data structure), determination, and so on. In addition, "decision" can also include receiving (for example, receiving information), accessing (for example, accessing data in memory), and so on. In addition, "decision" can also include analysis, selection, selection, creation, and so on.

In order to enable those skilled in the art to implement or use the present invention, a description of the disclosed aspects is provided above. For those skilled in the art, various modifications to these aspects are obvious, and the general principles defined in this case can also be applied to other aspects without departing from the spirit and protection scope of the present invention. Therefore, the present invention is not intended to be limited to the illustrated aspect of this case, but is consistent with the broadest scope of the principles and novel features disclosed in this case.

<p>100. . . system</p><p>102. . . Access terminal</p><p>104. . . Access point</p><p>106. . . Access point</p><p>108. . . Access point</p><p>110. . . Access point</p><p>112. . . Network entity</p><p>114. . . Power calibration coordination based on network monitoring</p><p>116. . . Power calibration based on training walk</p><p>118. . . Power optimization</p><p>120. . . Training walking path</p><p>202. . . Cube</p><p>204. . . Cube</p><p>206. . . Cube</p><p>208. . . Cube</p><p>210. . . Cube</p><p>212. . . Cube</p><p>214. . . Cube</p><p>216. . . Cube</p><p>302. . . Femto Cell Service Area</p><p>304. . . Femto Cell Service Area</p><p>306. . . Femto Cell Service Area</p><p>308. . . Femto Cell Service Area</p><p>310. . . Training walking path</p><p>402. . . Cube</p><p>404. . . Cube</p><p>406. . . Cube</p><p>408. . . Cube</p><p>410. . . Cube</p><p>412. . . Cube</p><p>502. . . Cube</p><p>504. . . Cube</p><p>506. . . Cube</p><p>508. . . Cube</p><p>510. . . Cube</p><p>602. . . Cube</p><p>604. . . Cube</p><p>606. . . Cube</p><p>608. . . Cube</p><p>702. . . Cube</p><p>704. . . Cube</p><p>706. . . Cube</p><p>708. . . Cube</p><p>802. . . Cube</p><p>804. . . Cube</p><p>806. . . Cube</p><p>808. . . Cube</p><p>810. . . Cube</p><p>812. . . Cube</p><p>902. . . Access terminal</p><p>904. . . Access point</p><p>906. . . Network entity</p><p>908. . . Transceiver</p><p>910. . . Transceiver</p><p>912. . . transmitter</p><p>914. . . Receiver</p><p>916. . . transmitter</p><p>918. . . Receiver</p><p>920. . . Network interface</p><p>922. . . Network interface</p><p>924. . . transmitter</p><p>926. . . Receiver</p><p>928. . . transmitter</p><p>930. . . Receiver</p><p>932. . . Processing system</p><p>934. . . Processing system</p><p>936. . . Processing system</p><p>938. . . Memory components</p><p>940. . . Memory components</p><p>942. . . Memory components/user interface equipment</p><p>944. . . User interface equipment</p><p>946. . . User interface equipment</p><p>1000. . . system</p><p>1002A. . . Macro Cell Service Area</p><p>1002B. . . Macro Cell Service Area</p><p>1002C. . . Macro Cell Service Area</p><p>1002D. . . Macro Cell Service Area</p><p>1002E. . . Macro Cell Service Area</p><p>1002F. . . Macro Cell Service Area</p><p>1002G. . . Macro Cell Service Area</p><p>1004A. . . Access point</p><p>1004B. . . Access point</p><p>1004C. . . Access point</p><p>1004D. . . Access point</p><p>1004E. . . Access point</p><p>1004F. . . Access point</p><p>1004G. . . Access point</p><p>1006A. . . Access terminal</p><p>1006B. . . Access terminal</p><p>1006C. . . Access terminal</p><p>1006D. . . Access terminal</p><p>1006E. . . Access terminal</p><p>1006F. . . Access terminal</p><p>1006G. . . Access terminal</p><p>1006H. . . Access terminal</p><p>1006I. . . Access terminal</p><p>1006J. . . Access terminal</p><p>1006K. . . Access terminal</p><p>1006L. . . Access terminal</p><p>1100. . . system</p><p>1110A. . . Femto access point</p><p>1110B. . . Femto access point</p><p>1120A. . . Access terminal</p><p>1120B. . . Access terminal</p><p>1130. . . User residence</p><p>1140. . . Wan</p><p>1150. . . Mobile Service Provider Core Network</p><p>1160. . . Access point</p><p>1200. . . Overlay map</p><p>1202A. . . Tracking area</p><p>1202B. . . Tracking area</p><p>1202C. . . Tracking area</p><p>1204A. . . Macro coverage area</p><p>1204B. . . Macro coverage area</p><p>1206A. . . Femto coverage area</p><p>1206B. . . Femto coverage area</p><p>1206C. . . Femto coverage area</p><p>1206D. . . Femto coverage area</p><p>1300. . . system</p><p>1310. . . Wireless device</p><p>1312. . . source</p><p>1314. . . Transmit (TX) data processor</p><p>1320. . . TX MIMO processor</p><p>1322A. . . Transceiver (XCVR)</p><p>1322T. . . Transceiver (XCVR)</p><p>1324A. . . antenna</p><p>1324T. . . antenna</p><p>1330. . . processor</p><p>1332. . . Data memory</p><p>1336. . . source</p><p>1338. . . TX data processor</p><p>1340. . . Demodulator (DEMOD)</p><p>1342. . . RX data processor</p><p>1350. . . equipment</p><p>1352A. . . antenna</p><p>1352R. . . antenna</p><p>1354A. . . Transceiver (XCVR)</p><p>1354R. . . Transceiver (XCVR)</p><p>1360. . . Receive (RX) data processor</p><p>1370. . . processor</p><p>1372. . . Data memory</p><p>1380. . . Modulator</p><p>1390. . . Transmit power control component</p><p>1392. . . Transmit power control component</p><p>1400. . . Device</p><p>1402. . . Module</p><p>1404. . . Module</p><p>1406. . . Module</p><p>1408. . . Module</p><p>1410. . . Module</p><p>1412. . . Module</p><p>1414. . . Module</p><p>1500. . . Device</p><p>1502. . . Module</p><p>1504. . . Module</p><p>1506. . . Module</p><p>1600. . . Device</p><p>1602. . . Module</p><p>1604. . . Module</p><p>1606. . . Module</p><p>1700. . . Device</p><p>1702. . . Module</p><p>1704. . . Module</p><p>1706. . . Module</p><p>1708. . . Module</p><p>1710. . . Module</p>

These and other exemplary aspects of the disclosure of this case will be described in the following specific embodiments and the scope of the patent application as well as in the accompanying drawings, where in the accompanying drawings:

Figure 1 is a simplified block diagram of several exemplary aspects of an embodiment of a communication system configured to control the transmission power of an access point;

Figure 2 is a flowchart illustrating several exemplary power control operations;

Figure 3 is a simplified diagram of an exemplary training walking path;

4 is a flowchart illustrating several exemplary operations for initializing the transmission power of an access point;

5 is a flowchart illustrating several exemplary operations for controlling the transmission power of an access point in conjunction with training walking;

Figure 6 is a flowchart illustrating several exemplary access point transmit power optimization operations;

Figure 7 is a flowchart illustrating several exemplary operations related to the use of measurement reports from a co-located macro cell service area;

FIG. 8 is a flowchart illustrating several exemplary operations for controlling transmission power based on coverage criteria and interference criteria;

Figure 9 is a simplified block diagram of several exemplary aspects of components that can be used in a communication node;

Figure 10 is a simplified diagram of a wireless communication system;

Figure 11 is a simplified diagram of a wireless communication system including a femto node;

Figure 12 is a simplified diagram illustrating a coverage area for wireless communication;

FIG. 13 is a simplified block diagram of several exemplary aspects of communication components; and

Figures 14-17 are simplified block diagrams of several exemplary aspects of an apparatus configured to control transmit power in the manner taught in this case.

According to convention, the various features shown in the figure may not be drawn to scale. Correspondingly, the size of each feature may be arbitrarily enlarged or reduced for clarity. In addition, some figures may be simplified for clarity. Therefore, the drawings may not illustrate all the components of a given device (for example, equipment) or method. Finally, throughout the specification and drawings, the same element symbols may be used to represent the same features.