Dynamic restrictive reuse scheduler

This application has priority to US Patent Provisional Application No. 60 / 678,258, named "Dynamic ASBR Scheduler", filed June 9, 2004, under 35 § 119 (e). The whole thing is taken here by citation.

The following description relates generally to wireless communications, and more specifically to scheduling resource allocation to user devices within a wireless network environment.

Wireless networking systems have become a popular means by which most people around the world have come to communicate with them. Wireless communication devices are becoming smaller and more powerful to meet customer needs and to improve portability and convenience. Increased processing power in mobile devices such as cellular phones has led to increased demand for wireless network transmission systems. Such systems are generally not updated as easily as the cellular devices that communicate on them. As the capabilities of mobile devices grow, it can be difficult to maintain old wireless network systems in a way that makes it easy to take full advantage of the capabilities of new and improved wireless devices.

More specifically, frequency division based technology separates the spectrum into separate channels by dividing the frequency into uniform chunks of bandwidth, eg, dividing the frequency band allocated for wireless cellular telephone communications. Can be divided into 30 channels, each of which can carry voice conversations or carry digital data using digital services. Each channel can be assigned to only one user at a time. One commonly used variant is orthogonal frequency division technology, which efficiently divides the entire system bandwidth into multiple orthogonal subbands. These subbands are also also referred to as tones, carriers, subcarriers, bins, and frequency channels. Each subband is associated with a subcarrier that can be modulated with the data. Using time division-based techniques, the band is temporally divided into successive time slices or time slots. Each user of the channel is given a time slice to send and receive information in a round robin fashion. For example, at any given time t, the user is given access to the channel for a short burst. Access is then switched to another user, who is given a short burst of time to send and receive information. The cycle of "shifting" continues, and eventually each user is given multiple transmit and receive bursts.

Code split-based techniques generally transmit over multiple frequencies available at any time within range. In general, the data is digitized and spread over the available bandwidth, where multiple users can be overlaid on the channel, and each user has a unique sequence code. Can be assigned. Users can transmit in broadband chunks of the same spectrum, where each user's signal is spread over the entire bandwidth by its own unique spreading code. This technique can be given to share, where one or more users can transmit and receive at the same time. Such sharing can be achieved through spectral diffusion digital modulation, where the stream of user bits is encoded and diffused across a very wide channel in a pseudo-random manner. To. The recipient is designed to recognize the unique sequence code associated with it, and reverts randomization to collect bits for a particular user in a coherent manner.

A typical wireless communication network (which employs, for example, frequency division technology, time division technology, and code division technology) can transmit data within one or more base stations and communicable areas that provide a communicable area. It includes one or more mobile (eg, wireless) terminals that can receive. A typical base station can simultaneously transmit multiple data streams for broadcast, multicast, and / or unicast services, where the data streams are of interest to mobile terminals. A stream of data that can be an independent reception. Mobile terminals within the communicable area of the base station may be interested in receiving one data stream, more than one data stream, or all data streams carried by the composite stream. is there. Similarly, a mobile terminal can transmit data to a base station or another mobile terminal. Such communication between a base station and a mobile terminal or between multiple mobile terminals can be degraded due to channel variation and / or interference power variation. For example, the above fluctuations can affect base station scheduling, power control and / or rate prediction for one or more mobile terminals.

Limited reuse is a technique designed to reduce cell-to-sector (or sector-to-sector) interference in wireless communication systems. Limited reuse is a global planning system that takes into account interference and channels measured by users of wireless networks. Limited reuse means reusing orthogonal resources (such as frequency, time, code, beam, spatial dimension, etc.) for selected users based on the channel quality associated with the selected user. seek. Traditional static limited reuse algorithms are inflexible and incapable of adapting data traffic bursts or data traffic of various fairness requirements, which results in an unstable user communication experience.

At least in view of the above, there is a need in the art for systems and / or methods that improve wireless communication and improve orthogonal resource allocation to users in wireless network environments.

The following is a simplified summary of one or more embodiments to provide a basic understanding of the embodiments of the present invention. This summary is not a broad overview of all expected embodiments and is not intended to recognize key or important elements of all embodiments, and either embodiment or Nor is it intended to describe the scope of all embodiments in detail. One purpose is to introduce the concept of one or more embodiments in a simplified form as a prelude to a more detailed description that will be introduced later.

According to one or more embodiments and corresponding disclosures thereof, various embodiments are described in connection with providing a packet-based dynamic limited reuse scheduler in a wireless network environment. According to one aspect, a method of dynamically scheduling a frequency set for reuse by a user device to reduce cell-to-cell interference comprises: Fairness metric for each user device in the wireless communication domain: To determine the overall channel peak request satisfaction metric based on the channel quality for multiple orthogonal resource sets for each user device, and to determine the overall scheduling metric for each user device, The overall scheduling metric is a function of the fairness metric and the channel peak request satisfaction metric. Multiple orthogonal resource centers according to relevant aspects A channel delay request satisfaction metric based on channel quality for each user device can be determined for each user device, and the total scheduling metric is in addition to the total channel peak request satisfaction metric. Alternatively, the channel delay request satisfaction metric can be adopted. The user device with the highest overall scheduling metric score may be given a portion of the corresponding orthogonal resource set. It is possible, and the method can be repeated until all user devices have been allocated the requested resources, or all orthogonal resource sets have been allocated.

In this document, the frequency set is used as an embodiment of the orthogonal resource set to illustrate a dynamic limited reuse algorithm. However, the various aspects described herein are in other embodiments of orthogonal resources such as time slots, carriers, codes, spatial dimensions, frequency interlace / time interlace and beam forming beams. It can be applied directly.

According to another aspect, a system that facilitates dynamic limited reuse frequency scheduling in a wireless network environment is limited reuse scheduling that determines an overall scheduling metric for each user device in the wireless network environment. It includes an element, a peak element that determines an overall channel peak request satisfaction metric for each user device, and a delay element that determines a channel delay request satisfaction metric for each user device. The dynamic limited reuse scheduling element can determine the fairness metric for each user device using the same grade of service technology and proportional fairing technology, or the like, which is the overall channel peak request satisfaction metric. A winning user device that can be multiplied by one or more of the channel delay request satisfaction metrics and can be given a frequency set during a given round of frequency set assignments. Identify. The system may additionally include a sorter element that excludes the winning user device from subsequent allocation iterations to ensure that all user devices receive the frequency allocation. Alternatively, the sorter element can include the winning user device in subsequent assignment iterations to allow the user device to obtain multiple frequency set assignments.

According to yet another aspect, a device that facilitates scheduling of frequency allocation for user devices in a wireless communication environment is a means for determining a fairness metric for each user device in the communication environment, each user. Means for determining the overall channel peak request satisfaction metric for the device, means for determining the channel delay request satisfaction metric for each user device, and for determining the overall scheduling metric score for each device. The scheduling metric score is a function of one or both of the total channel peak request satisfaction metric and the channel delay request satisfaction metric and the fairness metric. Comprehensive scheduling metric scores for individual user devices can be compared, and the user device with the highest score can be given a frequency set.

Another aspect provides a computer-readable medium with computer-executable instructions stored therein to do the following, which instructions are a fairness metric for each user device in a wireless network environment. Instructions for determining the overall channel peak request satisfaction metric for each user device, and instructions for determining the channel delay request satisfaction metric for each user device. Moreover, the computer readable medium may include instructions for determining a scheduling metric score based on the previous metric, which is a winning user whose frequency set can be given to the user device. It can be adopted to determine the device.

Yet another aspect involves a microprocessor that executes instructions for dynamic frequency set scheduling in the wireless communication network area, the instructions comprising: of multiple user devices in the network area. Evaluate each of the fairness metric, the overall channel peak request satisfaction metric, and the channel delay request satisfaction metric for each; the overall channel peak request satisfaction metric and the cha. Determine the overall scheduling metric score for each user device based on at least one of the flannel delay request satisfaction metrics and the fairness metric; and for other user devices in the network area. Giving a frequency set to the user device with the relatively highest overall scheduling metric.

For the performance of the above and related objectives, one or more embodiments include features described in great detail below, particularly those set forth in the claims. The following description and accompanying drawings describe in detail certain exemplary embodiments of one or more embodiments. These embodiments, however, are implied, with the exception of a few of the various methods adopted within the method, and the described embodiments are such. It is intended to include all aspects and their equivalents.

<figref num="1">Figure 1 illustrates a diagram that facilitates an understanding of limited reuse and related resource allocation.</figref><figref num="2">FIG. 2 is an explanatory diagram of a system that facilitates the dynamic allocation of network resources using limited reuse according to one or more embodiments.</figref><figref num="3">FIG. 3 is an explanatory diagram of a system that facilitates packet-based scheduling of frequency sets utilizing dynamic limited reuse scheduling techniques.</figref><figref num="4">FIG. 4 illustrates a system that facilitates dynamic limited reuse scheduling of frequency reuse sets based on channel request satisfaction and channel delay according to various aspects described herein.</figref><figref num="5">FIG. 5 is an explanatory diagram of a system that facilitates dynamically adjusting the power consumption for transmission to a user device having a sufficiently strong channel state according to various aspects.</figref><figref num="6">FIG. 6 is an explanatory diagram of a system that facilitates giving the user multiple reuse frequency sets.</figref><figref num="7">FIG. 7 illustrates a system that facilitates dynamic packet-based limited reuse scheduling of communication frequency reuse sets without the need to assign connections to static frequency reuse sets.</figref><figref num="8">FIG. 8 is an explanatory diagram of a system that facilitates the assignment of frequency reuse sets to user devices based on the evaluation of the channel request satisfaction metric for the user device.</figref><figref num="9">FIG. 9 illustrates a method for providing dynamic frequency reuse set assignments to user devices in a wireless network according to various embodiments.</figref><figref num="10">FIG. 10 illustrates methods for dynamically scheduling frequency reuse set allocations and mitigating resource waste according to various embodiments.</figref><figref num="11">FIG. 11 illustrates a method for dynamically assigning a frequency reuse set to a user device in a wireless communication environment while allowing the user device to acquire multiple frequency sets.</figref><figref num="12">FIG. 12 is an explanatory diagram of a wireless network environment that can be adopted with various systems and methods described herein.</figref>

Detailed explanation Various embodiments are described herein with reference to the drawings, in which the same reference numerals are used to refer to the same elements throughout. In the description below, for purposes of explanation, many specific details are provided to provide a complete understanding of one or more embodiments. However, it is clear that such embodiments can be implemented without these specific details. In another case, well-known structures and devices are shown in block diagram format to facilitate the description of one or more embodiments.

As used in this application, the terms "component", "system", and others are computer-related entities, any hardware, hardware-to-software combinations, software, or running software. Is intended to call. For example, components can be, but are not limited to, processes, processors, objects, executables, threads of execution, programs, and / or computers running on the processor. One or more components can reside inside a process and / or inside a thread of execution, and one component can be centralized on one computer and / or two or more. It can be placed between more computers. Similarly, these components can be run from computer-readable media with various data structures stored therein. A component is one or more data packets (eg, in a local system, in a distributed system, and / or as a signal to another one across a network such as the Internet with another system. It can be transmitted through local and / or remote processes that follow a signal that has data from one component that is exchanging information with the component.

Moreover, various embodiments are described herein in relation to the subscriber bureau. Subscriber stations may also be similarly referred to as systems, subscriber units, mobile stations, mobiles, remote stations, access points, base stations, remote terminals, access terminals, user terminals, user agents, or user devices. it can. Subscriber stations include cellular phones, cordless phones, Session Initiation Protocol (SIP) phones, wireless local loop (WLL) stations, personal digital assistants (PDAs), and wireless. It can be a handheld device capable of connecting, or another processing device connected to a wireless modem.

In addition, the various aspects or features described herein may be provided as a method, as a device, or as an article on manufacture using standard programming and / or engineering techniques. it can. As used herein, the term "manufacturing article" is intended to include computer programs accessible from any computer-readable device, carrier, or medium. For example, computer-readable media include magnetic storage devices (eg, hard disks, floppy disks®, magnetic tapes, ...), optical disks (eg, compact disks), digital It can include, but is not limited to, multipurpose discs (DVDs: digital versatile discs) ...), smart cards, and flash memory devices (eg, cards, sticks, key drives ...).

With reference to the drawings here, FIG. 1 illustrates a diagram 100 that facilitates an understanding of limited reuse and resource allocation associated therewith. One aspect of limited reuse is to intelligently allocate frequencies for reuse by a user selected based on the user's channel quality. For CDMA systems, an "active set" can be specified for each user for handoff purposes. Sectors in the user's active set usually cause interference with the user's reception on the forward link (FL), while sector transmitters are on the user on the reverse link (RL). Is interfered with by the transmission of. Interference reductions can be achieved in both FL and RL to avoid interference from various sectors in the user's active set. A frequency reuse allocation algorithm based on the user's active set provides a signal-to-noise ratio (SINR) of 3.5 dB with 25% bandwidth partial loading. Simulations and analyzes show that it produces improvements in ratio).

The scheduler in the wireless network can be modified according to various embodiments described herein to take advantage of SINR improvements through limited reuse. When discussing voice transmission traffic, voice capability is often limited by the SINR of the worst user in the network. To occupy a small portion of the bandwidth available to voice users over a relatively long period of time, the capability improvement assigns the user a static frequency reuse set to improve the user SINR over the duration of the call. It can be realized by. However, in the case of data traffic, traditional static limited reuse algorithms provide "bursty" data traffic (eg, intermittent traffic, etc.) and / or variable fairness of traffic. Not flexible enough to adapt to fairness requirements. When users send / receive explosive traffic, traditional systems have different SINRs, available bandwidth, and loads provided (eg, from other users on a given reuse set). Requires a trade-off to be made between multiple frequency sets with. If fairness criteria such as equal grade of service (EGoS) or proportional proportional (EGoS) fairness need to be strongly demanded for users from different reuse sets, the scheduler Can be more complicated.

Diagram 100 shows a U with a communication bandwidth of 7 frequencies.₀From U₆Illustrating a simplified scenario divided into, seven frequencies can be assigned to different sectors, and multiple sectors can transmit and receive information over those frequencies. In the limited reuse algorithm of the specific example below, each sector is specified with a value of 0,1, or 2. The total bandwidth available in a network is divided into seven frequency sets with total reuse, 1/3 reuse, and 2/3 reuse. Each reuse frequency set is then labeled with a 3-bit binary mask, where the "1" at the i-th position indicates that it is used by the sector with the value i. For example, 110 indicates a 2/3 frequency reuse set that is used by sectors with values 0 and 1 and not by sectors with values 2. Frequency set label {U₀, U₁, U₂, U₃, U₄, U₅, U₆} Is given by {111,110,101,011,100,010,001}. However, it is recognized that arrangements with different labels are possible. For example, a 3-bit mask value can be adopted to label a frequency set (eg, where 111 represents frequency set 7, 001 represents frequency set 1, etc.). With frequency planning, the user can avoid major interference by using a 1/3 reuse frequency set or a 2/3 reuse frequency set.

In 3rd generation networks, fairness among multiple data users is protected by the scheduler. In networks where forward link transmissions to users are time-multiplexed, the user with the highest scheduling metric is generally scheduled to transmit over the entire scheduling time slot. Scheduling metrics are typically calculated based on channel demand satisfaction (desirability) as well as fairness metrics and utilize multi-user diversity (MUD). For example, λ_iRepresents the throughput of user i for the specified window, and μ_iAnd μ^-_iRepresent the instantaneous spectral efficiency and the average spectral efficiency of User I, respectively. Fairness metric F_iIs given by: For the EGoS scheduler, F_i= 1 / λ_i (1) And against the proportional fair scheduler F_i= μ^-_i/ λ_i (2) Is. The channel request satisfaction metric is given by: T_i= μ_i/ μ^-_i (3)。

The scheduling metric can be calculated as the output of the metric integration function of the fairness metric and the channel request satisfaction metric. The scheduling metric is another QoS-related metric Q to make the final scheduling decision._iCan be further integrated with. In the present invention, only the fairness metric is used to illustrate the flexibility of the dynamic limited reuse scheduler. In one embodiment, the integrated functions are products as given by: S_i= F_iT_i (4)。

In one other embodiment, the function is the product of each metric exponentiated by some exponents α and β, given by: S_i= F_i^αT_i^β (5)。

In yet another embodiment, the function is a weighted sum of each metric exponentiated by some exponents α and β, given by: S_i= aF_i^α+ bT_i^β (6)。

In yet another embodiment, the function is a powered weighted metric maximum by some exponents α and β, given by: S_i= max (aF)_i^α, bT_i^β) (7)。

FIG. 2 is an explanatory diagram of a system 200 that facilitates the dynamic allocation of network resources using limited reuse according to one or more embodiments. The dynamic limited reuse scheduler element 202 is operationally connected to each of the wireless network 204 and the (plural) user devices 206. The wireless network 204 can include one or more base stations, transceivers, etc., which transmit communication signals and receive communication signals from one or more user devices 206. Moreover, the wireless network 204 can provide communication services to the user device 206 along with various multiple access technologies, combinations thereof, or any other suitable wireless communication protocol, as valued by those skilled in the art. For example, these technologies include code division multiple access (CDMA) systems, frequency division multiple access (FDMA) systems, and time division multiple access (TDMA) systems. Multiple access (multiple access) systems, orthogonal frequency division multiple access (OFDMA) systems, interleaved (IFDMA) systems, localized FDMA (LFDMA) systems, spatial division multiple access (SDMA) systems It can be used for division multiple access systems, quasi-orthogonal multiple access systems, etc. IFDMA is also referred to as distributed FDMA, and LFDMA is also referred to as narrowband FDMA or standard FDMA. OFDMA systems are orthogonal frequency division multiplexing (OFDM). Use multiplexing). OFDM, IFDMA, and LFDMA effectively divide the entire system bandwidth into multiple (K) orthogonal frequency subbands. These subbands are also also referred to as tones, subcarriers, bins, and others. Each subband is with data It is associated with each subcarrier that can be modulated into. OFDM transmits modulation symbols within the frequency domain on all or a subset of the K subbands. IFDMA transmits modulation symbols within a time domain on subbands that are uniformly distributed over K subbands. LFDMA transmits modulation symbols within the time domain and generally on adjacent subbands.

The user device 206 can be, for example, a cellular telephone, a smartphone, a PDA, a laptop, a wireless PC, or any other suitable communication device that allows the user to communicate with the wireless network 204 via the communication device. The user device 206 can also provide feedback to the wireless network 204, enhancing the performance of the scheduler. For FL scheduling, the channel and interference states at user device 206 can be measured by 206 and are explicitly fed back to 204 and 202. For RL scheduling, the channel state of the user device and the level of interference with respect to another set of orthogonal resources can be measured directly at 204 based on the pilot sent by 206. User device 20 The RL transmission power of 6 can be clearly fed back to 204 and 202. Dynamic Limited Reuse Scheduler Element 202 is a packet-based scheduler that employs frequency reuse as a scheduling dimension in addition to EGoS and proportional fairing criteria without requiring the use of static frequency reuse sets. it can. The dynamic limited reuse scheduler element 202 can determine the scheduling metric in a manner similar to that described above for FIG. 1 to facilitate frequency set assignment to one or more user devices 206. .. Moreover, the dynamic limited reuse scheduler element 202 can employ a dynamic limited reuse algorithm, facilitating the evaluation of channel request satisfaction. The dynamic limited reuse scheduler element 202 is F as described above._iFairness criteria can be evaluated to determine, which can be extended by the request satisfaction metric when allocating frequency reuse sets. Two-channel request satisfaction metrics are defined for various embodiments and allow limited reuse frequency set selection as detailed below. For the rest of the specification, one specific embodiment of a dynamic limited reuse scheduler in which the orthogonal resource set is a frequency set is described for ease of understanding.

FIG. 3 is an explanatory diagram of System 300 that facilitates packet-based scheduling of frequency sets utilizing dynamic limited reuse scheduling techniques. System 300 has a dynamic limited reuse scheduler element 302 that is operationally associated with wireless networks 304 and one or more user devices 306, each of which in turn is operationally associated with another. Equipped. The dynamic limited reuse scheduler element 302 further comprises a channel evaluation element 308, facilitating scheduling connections with the best relative channel state over the available frequency set. Moreover, in a scenario in which a more preferred frequency set of a given connection is occupied in that scenario, channel evaluation element 308 later schedules to provide contention resolution for dynamic limited reuse scheduler element 302. Because of the delayed connection can be promoted.

The dynamic limited reuse scheduler element 302 further comprises a frequency analyzer 310, which can evaluate the overall available bandwidth within the wireless network 304, and analyze such bandwidth into a frequency set. For example, in cases such as those described with respect to FIG. 1, the frequency analyzer 310 can assign a frequency set to a sector for reuse for exclusion of other frequencies. Such assignments can be, for example, the entire reuse set, the 2/3 reuse set, the 1/3 reuse set, and so on.

FIG. 4 illustrates a system 400 that facilitates dynamic limited reuse scheduling of frequency reuse sets based on channel request satisfaction and channel delay according to various aspects described herein. The system 400 comprises a dynamic limited reuse scheduler element 402, which is operationally associated with each of the wireless networks 404 and one or more user devices 406. The dynamic limited reuse scheduler element 402 comprises a channel evaluation element 408 and a frequency analyzer 410, which facilitates scheduling connections with the best relative channel state over the available frequency set. And the frequency analyzer 410 determines the appropriate bandwidth division for frequency allocation to user devices within the sector and / or paging area.

The channel evaluation element 408 comprises a peak element 412 and a delay element 414, the peak element 412 determines the channel peak request satisfaction to facilitate connection scheduling, and the delay element 414 thereof. The most preferred frequency set delays the scheduling of currently fully scheduled connections. In systems that do not use limited reuse, the channel peak element is simply a function of the instantaneous channel state and the average channel state. In a limited reuse system, both the channel peak element 412 and the channel delay element 414 take into account the different levels of interference the user receives at different frequency sets. For example, the peak element 412 can evaluate the channel peak request satisfaction factor, and as a result, for each frequency set j, the channel peak request satisfaction factor of the user i is given by the following equation: T_{i, j}= μ_{i, j}/ μ^-_i (8) Where μ_{i, j}Is the instantaneous spectral efficiency of user i with respect to the frequency set j, and μ^-_iIs the average spectral efficiency for all limited reuse frequency sets. Average spectral efficiency is the filtered spectral efficiency μ^-_{i, j}Minutes each limited reuse frequency set U_jAs an arithmetic mean of, or | U_j| μ^-_{i, j}Can be calculated as a weighted average of, where | U_j| Is U_jRepresents the size of.

The total channel peak request satisfaction factor for user i is given by: T_i= max_{j {free frequency set}}T_{i, j} (9) Here, maximization is performed for an unlimited frequency set that is not yet fully scheduled. For example, a sector scheduler with a value of 0 can limit the channel request satisfaction factor that is being calculated for a well-scheduled frequency set, and not for one of the 011,010 and 001 sets. Factor T_iReflects the user's instantaneous channel request satisfaction for the user's best available frequency set with respect to the user's average channel quality. Channel peak request satisfaction factor T_iDoes not reflect the potential benefits of waiting for the user to make an unavailable frequency set available. Rather, such can be defined by the channel delay request satisfaction metric.

The delay element 414 can determine the second limited reuse channel request satisfaction metric, the channel delay request satisfaction, which is defined by the following equation: D_{i, j}= μ_{i, j}/ max_{k {scheduled frequency set}}μ μ_{i, k} (Ten) D if no frequency set is scheduled_{i, j}The denominator of can be replaced by the minimum spectral efficiency for all frequency sets. The total delay request satisfaction factor is given by: D_i= max_{j {free frequency set}}D_{i, j} (11) Here, maximization is performed for an unlimited frequency set that is not yet fully scheduled. In that way, channel delay request satisfaction can be defined as the ratio between the maximum instantaneous spectral efficiency for all free frequency sets and the maximum instantaneous spectral efficiency for all unavailable frequency sets. is there.

The comprehensive limited reuse scheduling metric utilized by the dynamic limited reuse scheduler element 402 can therefore be one of the following forms: when the product is used to integrate the metrics: To<maths num="1"><img file="JP5155366B2_D0001.tif" /></maths>

As explained above, the integrated function can also be another function such as weighted sum, maximum value, etc. For each time slot, the dynamic limited reuse scheduler element 402 is capable of ranking scheduling metrics and assigning the appropriate number of subcarriers in the user's winning frequency set to the top user. be able to. Scheduled subcarriers can then be excluded from the free (s) of frequency sets, and metrics can be recalculated for users who have not yet been scheduled. This process can be repeated until all subcarriers have been assigned. The scheduling metric is another QoS-related metric Q to make the final scheduling decision._iCan be further integrated with. In this aspect, only the fairness metric is used to illustrate the flexibility of the dynamic limited reuse scheduler.

FIG. 5 is an explanatory diagram of the system 500 that facilitates dynamically adjusting the power consumption for transmission to a user device having a sufficiently strong channel state according to various aspects. System 500 comprises a dynamic limited reuse scheduler element 502, a wireless network 504 and one or more user devices 506, each of which operates with each other as described in detail above with respect to the previous drawings. Related above. The dynamic limited reuse scheduler element 502 includes a frequency analyzer 510 and a channel evaluation element 508, and the channel evaluation element 508 includes a peak element 512 and a delay element 514, respectively. The peak element 512 can determine the channel peak request satisfaction metric, which is the overall scheduling metric, S._i, Can be adopted with the channel delay request satisfaction metric as described with respect to FIG. Comprehensive scheduling metric, S_i, Can be utilized by the dynamic limited reuse scheduler element 502 when assigning a frequency set to one or more user devices 506.

The dynamic limited reuse scheduler element 502 further comprises a low power element 506, which facilitates power savings based at least in part on the channel quality associated with one or more user devices 506. Limited reuse can introduce partial loading of bandwidth for a limited set in each sector. For example, in Diagram 100 of FIG. 1, the set of 011,010 and 001 is not used in sectors with a value of 0. The low power element 516 of the dynamic limited reuse scheduler element 502 can transmit with reduced power in a set of ports limited to the user device 506 with good channel state. In this way, the loss of bandwidth partial loading can be avoided. To allow for total reuse, equations (9) and (11) can be evaluated for all unscheduled frequency sets without the limitation of limited reuse sector values. Moreover, the spectral efficiency of the limited frequency set can be taken into account for the reduced transmit power.

FIG. 6 is an explanatory diagram of the system 600 that facilitates giving the user multiple reuse frequency sets. The system 600 comprises a dynamic limited reuse scheduler 602 with a channel evaluation element 608, a frequency analyzer 610 and a low power element 616, which in operation on wireless networks 604 and one or more user devices 606. Be related. The channel evaluation element 608 includes a peak element 612 and a delay element 614. The peak element 612 determines the channel peak request satisfaction metric for each user device 606. Delay element 614 evaluates a channel delay request satisfaction metric for each user device. These metrics are then adopted by the Dynamic Limited Reuse Scheduler 602 to determine the winning user device. The winning user device can then be assigned the reuse frequency set in question.

The dynamic limited reuse scheduler 602 further comprises a sorter element 618 to facilitate the relaxation of various constraints associated with limited reuse scheduling and the provision of multiple reuse frequency set assignments. The sorter element 618 can ensure that the user device 606, which has been assigned the reuse frequency set in the previous round of the channel request satisfaction assessment, is not excluded from future iterations of giving the frequency set. For example, when adopting a static limited reuse scheduler protocol, a reuse frequency set based on a high overall channel request satisfaction score (eg, a function of the channel peak request satisfaction and delay request satisfaction metrics). Assigned / given user devices may generally be excluded from future iterations of frequency allocation because the user device has been successfully assigned a reuse frequency set. Because it is closed. By relaxing the limitation of this exclusion, a given user device 606 can be given multiple frequency sets. The final channel assignment for a user device 606 can be a set of all subcarriers to which the user device 606 is assigned across multiple frequency sets. Moreover, multiple frequency set assignments can increase the peak rate for such users, which in turn alleviate the delays associated with the transmission of communications.

FIG. 7 illustrates a system 700 that facilitates dynamic packet-based limited reuse scheduling of communication frequency reuse sets without the need to assign connections to static frequency reuse sets. System 700 comprises multiple components similar to the system and / or components described with respect to the previous drawings and is operationally connected to wireless networks 704 and one or more user devices 706. Includes limited reuse scheduler 702. The dynamic limited reuse scheduler element 702 further comprises a channel evaluation element 708. The channel evaluation element 708 is a total channel request satisfaction metric as a function of the channel peak request satisfaction metric determined by the peak element 712 and the channel delay request satisfaction metric determined by the delay element 714 on a per-user device basis. To determine. Moreover, the dynamic limited reuse scheduler element 702 comprises a frequency analyzer 710, a low power element 716, and a sorter element 718. As described in detail above with respect to the previous drawing, the frequency analyzer 710 evaluates the overall available bandwidth within and / or within that region of the wireless network 704, and the low power element 716 is of high quality. Facilitates low power transmission to users with connections, and sorter element 718 facilitates multiple reuse frequency set assignments.

The system 700 can further include a memory 720, the memory is operationally connected to a dynamic limited reuse scheduler element 702, and channel request satisfaction algorithms, metrics, available frequency sets, user device frequencies. Information related to allocation, etc., and any other suitable information related to providing one or more users with dynamic limited reuse scheduling of frequency reuse sets. Remember. Processor 722 can be operationally connected to dynamic limited reuse scheduler element 702 (and / or memory 720) and is related to fairness criteria, request satisfaction metrics, frequency reuse, and more. Facilitates the analysis of information. The processor 722 is a dedicated processor for parsing and / or generating information received by the dynamic limited reuse scheduler element 702, controlling one or more components of system 700. To be a processor and / or to analyze and generate the information received by the dynamic limited reuse scheduler element 702, and to control one or more components of the system 700. It should be understood that it can be a processor that does.

The memory 720 can further store protocols related to generating frequency allocations, metrics, etc., so that the system 700 provides dynamic limited reuse frequency hopping as described herein. The stored protocol and / or algorithm can be adopted to do so. The data storage (eg, memory) element described herein can be either a volatile memory or a non-volatile memory, or a volatile memory. It is understood that it is possible to include both moly and non-volatile memory. For explanatory and non-restrictive purposes, non-volatile memory includes read-only memory (ROM), programmable ROM (PROM), and electrically programmable ROM (EPROM). It can include programmable ROM), electrically erasable ROM (EEPROM) or flash memory. Volatile memory is random access memory (RAM) memory) can be included, which acts as an external cache memory. For explanatory purposes and not to limit, RAM is Synchronous RAM (SRAM: synchronous RAM), Dynamic RAM (DRAM: dynamic RAM), Synchronous DRAM (SDRAM: synchronous DRAM), Double Data Rate SDRAM. It is available in many formats such as (DDR SDRAM: double data rate SDRAM), enhanced SDRAM (ESDRAM: enhanced SDRAM), synchlink DRAM (SLDRAM: Synchlink DRAM) and direct Rambus RAM (DRRAM: direct Rambus RAM). The memory 720 of the system and method of interest is intended to include these and other suitable types of memory, but is not limited thereto.

FIG. 8 is an explanatory diagram of System 800 that facilitates the allocation of frequency reuse sets to user devices based on the evaluation of the channel request satisfaction metric for the user device. System 800 comprises a dynamic limited reuse scheduler 802 that is operationally connected to wireless networks 804 and one or more user devices 806. The dynamic limited reuse scheduler 802 is similar to the scheduler 702 and includes a channel evaluation element 808 and a frequency analyzer 810 in it. Channel evaluator 808 facilitates the determination of various metrics related to frequency set allocation, and frequency analyzer 810 evaluates the total available amount of bandwidth and is described in detail with respect to FIG. As such, it produces multiple frequency reuse subsets, which are used by various users to mitigate interference between the user device 806 and the base tower transmission within one or more sectors of the wireless network 804. It can be assigned to device 806. Moreover, the dynamic limited reuse scheduler 802 comprises a low power element 816 and a sorter element 818. The low power element 816 is attached to one or more user devices 806 at low power with the determination that one or more user devices 806 have sufficiently strong channel quality (eg, sufficient resources). Can send multiple) signals. The sorter element 818 can optionally include a user device 806 that has already been assigned one or more frequency reuse sets within the set of users who still need the assignment, while mitigating channel delay. Facilitates increasing the peak transmission rate for the user. The channel evaluation element 808 includes a peak element 812 and a delay element 814. Peak element 812 evaluates the channel peak request satisfaction metric for each user device 806, and delay element 814 evaluates the channel delay request satisfaction metric. Evaluate to determine if the channel connection should be delayed. Either or both of these metrics can be adopted with the fairness metric derived by the Limited Reuse Scheduler 802, and a frequency reuse set can be assigned to that user device. Identify the winning user device 806.

System 800 includes memory 820 and processor 822, as described in detail above with respect to FIG. In addition, AI element 824 can be operationally associated with dynamic limited reuse scheduler element 802, and inference about channel connection quality, winning user device 806 in subsequent allocation rounds. Inferences about including / excluding are possible, inferences about whether channel delay is desired (eg, due to lack of available reuse sets, ...), and so on. As used herein, the term "inference" or "inference" refers to the state of the system, the state of the environment, and / or from a set of observations as captured via events and / or data. Or the process of reasoning or reasoning about a user's condition is commonly referred to. Inferences can be employed to identify specific content or actions, or, for example, can generate probability distributions for states. Inference can be probable-that is, the calculation of the probability distribution for the state of interest based on the consideration of data and events. Inference can also call the techniques adopted to construct higher level events from a set of events and / or data. Such inference is a set, whether or not the events are very closely related in time, and whether or not the events and data come from one or more events and data sources. The result is the construction of new events or new actions from the observed events and / or from the stored event data.

According to one example, the AI element 824 has an appropriate frequency based on, for example, the available frequency set, the total number of user devices 806, the channel request satisfaction metric, the user device resource requirements, etc. Reuse set allocation can be inferred. According to this example, the user device 806 is sufficient, such as bandwidth, to justify excluding the user device from the resource allocation despite the high metric score for that user device 806. It is possible to decide to have a good transmit resource allocation. Along with processor 814 and / or memory 812, AI element 824 can infer that such user devices should be excluded in the current round of frequency allocation. In such cases, the AI element 824 can facilitate resource allocation in the most efficient way possible, such as to facilitate bandwidth allocation and reuse, to reduce transmission costs, and so on. The above example is exemplary in nature and is intended to limit the range of inferences that can be performed by AI element 824, or the way AI element 824 makes such inferences in that way. Not doing is appreciated.

With reference to Figure 9-11, the methodology involved in providing ancillary system resource allocation is illustrated. For example, the method can relate to packet-based dynamic limited reuse scheduling in an OFDM environment, an OFDMA environment, a CDMA environment, a TDMA environment, or any other suitable wireless environment. On the other hand, for the purpose of simplifying the description, the method is shown and described as a series of actions, but certain actions are described herein according to one or more embodiments. It is understood and valued that the method is not limited by the order of actions so that it can occur in a different order and / or at the same time as another action as shown and explained. Those skilled in the art will appreciate and appreciate that methods may instead be represented as a series of correlated states or events, as in a state diagram. Moreover, not all of the illustrated actions may be required to perform the method according to one or more embodiments.

FIG. 9 illustrates method 900 for providing dynamic frequency reuse set assignments to user devices in a wireless network according to various embodiments. In 902, Channel Peak Request Satisfaction Metric, T_i, Can be determined for each user device in the set of all user devices in the network area or in a subset thereof. For example, satisfying peak demands for each user / device The degree metric can be derived using equations (8) and (9) as described above for FIG. In 904, Channel Delay Request Satisfaction Metric, D_i, Can be evaluated for each user device in relation to equations (10) and (11), as similarly described with respect to FIG. Once such a metric has been evaluated for all user devices in the set, in 906, the overall channel request satisfaction metric, S, is used using equation (12)._iTo determine, one or both metrics are the fairness metric for the user device, F, as described with respect to Figure 1._i, Can be multiplied. Once the total channel request satisfaction metric has been derived for each user device in the set, the winning user device (eg, maximum S)._iThe user device with the value) can be identified at 908.

At 910, for each time slot, the winning user device can be assigned an appropriate number of subcarriers within the user device's winning frequency set. At 912, the scheduled subcarriers can then be excluded from the free (s) frequency set, and method 900 returns to 902, where the metric is not yet scheduled for the user. Can be recalculated for the device. Method 900 can be repeated until all subcarriers have been assigned. In this way, Method 900 can easily provide packet-based, dynamic, limited reuse scheduling of frequency sets without the need to assign connections to static frequency reuse sets.

FIG. 10 illustrates a method 1000 for dynamically scheduling frequency reuse set allocations and mitigating resource waste according to various embodiments. In 1002, Comprehensive Scheduling Metric, S_iIs evaluated for each user device in the set of user devices communicating over the wireless network. Metric S_iCan be a function of multiple metrics, as explained above with respect to Figures 1-4 and equations (1)-(12). At 1004, the winning user device can be identified for each round of metric evaluation. At 1006, the appropriate number of subcarriers in the user device's winning frequency set. In 1008, winning user devices can be excluded to ensure that other user devices receive frequency assignments during subsequent iterations of Method 1000 (eg, user devices). Will be removed from the list of). The method can be returned to 1002 for further iteration until all user devices in the set have been assigned one set of frequencies and / or one set of subcarriers.

At 1010, the channel state can be evaluated, and if the state is guaranteed, transmission at 1012 to a user device with good channel state is due to a limited set of bandwidth. It can be performed with low power in a limited set of ports to mitigate partial loading of. Equations (4)-(7) and (9) are still scheduled to allow universal reuse. Not all frequency sets can be evaluated, and without the limitation of the limited reuse values described with respect to FIG. In this way, Method 1000 can facilitate reducing power consumption in order to reduce transmission costs.

FIG. 11 illustrates a method 1100 for dynamically assigning a frequency reuse set to a user device in a wireless communication environment while allowing the user device to acquire multiple frequency sets. At 1102, channel peak request satisfaction metric, T_i, Can be determined for each user device in a set of user devices in the network area or in a subset thereof. The peak request satisfaction metric for each user device can be derived using equations (8) and (9) described above with respect to FIG. In 1104, Channel Delay Request Satisfaction Metric, D_i, Can be evaluated for each user device in relation to equations (10) and (11), as similarly described with respect to FIG. Once such a metric has been evaluated for all user devices in the set, in 1106, the total channel request satisfaction metric, S, is used using Eq. (12)._iTo determine, one or both metrics are the fairness metric for the user device, F, as described with respect to Figure 1._i, Can be multiplied. Once satisfied with the comprehensive channel request Once the degree metric has been derived for each user device in the set, the winning user device (eg, maximum S)_iThe user device with the value) can be identified in 1108.

At 1110, for each time slot, the winning user device can be assigned an appropriate number of subcarriers within the user device's winning frequency set. In 1112, winning user devices can be included in the remaining list of unscheduled user devices to allow user devices to preferentially acquire multiple frequency sets. As such, if the frequency set allocation at 1110 is inadequate and, as a result, the winning device potentially has the highest overall scheduling metric score in subsequent scheduling rounds, the user device will have the next frequency: It is possible to be allowed to get a set assignment. Method 1100 can then return to 1102 for further iteration of dynamic scheduling. The final channel allocation of a user device can be a collection of all subcarriers acquired by the user device over multiple frequency set allocation rounds, which mitigates delay while peaking communication to the user device. It can promote the increase of the rate.

FIG. 12 shows a specific example wireless communication system 1200. The wireless communication system 1200 illustrates one base station and one terminal for the sake of brevity. However, it is valued that the system can include more than one base station and / or more terminals, wherein additional base stations and / or terminals are exemplified below. It may be the same as or different from the base station and terminal of. Moreover, base stations and / or terminals can employ the systems (FIG. 1-8) and / or methods described herein (FIG. 9-11) to facilitate wireless communication between them. However, it is evaluated.

Now, with reference to FIG. 12, on the downlink, at access point 1205, the transmit (TX) data processor 1210 receives, formats, encodes, interleaves, and modulates the traffic data ( Or symbol map) and give a modulated symbol (data symbol). The OFDM modulator 1215 receives and processes data and pilot symbols, and provides a stream of OFDM symbols. The OFDM modulator 1220 multiplexes the data and pilot symbols over the appropriate subbands, gives a zero signal value for each unused subband, and N subs between each OFDM symbol period. Gets a set of N transmit symbols for a band. Each transmit symbol can be a data symbol, a pilot symbol, or a signal value of zero. Pilot symbols can be sent consecutively in each OFDM symbol period. Alternatively, the pilot symbol can be time division multiplexing (TDM), frequency division multiplexing (FDM), or code division multiplexing (CDM). OFDM modulator 1220 uses N point IFFT to N Each set of transmission symbols can be converted to a time domain to get a "converted" symbol containing N time domain chips. The OFDM modulator 1220 typically repeats a portion of each transformed symbol to obtain the corresponding OFDM symbol. The repeated portion is known as a periodic prefix and is used to overcome delayed spread in the radio channel.

The transmitter unit (TMTR) 1220 receives, converts a stream of OFDM symbols to one or more analog signals, and tunes (eg, amplifies, filters, and frequency-upconverts) the analog signals. Generates a downlink signal suitable for transmission over a wireless channel. The downlink signal is then transmitted to the terminal via antenna 1225. At terminal 1230, antenna 1235 receives a downlink signal and feeds the received signal to receiver unit (RCVR) 1240. The receiver unit 1240 tunes the received signal (eg, filters, amplifies, frequency downconverts), and digitizes the tuned signal to take a sample. The OFDM demodulator 1245 removes the periodic prefix attached to each OFDM symbol and uses the N-point FFT to convert each received transformed symbol into a frequency domain, between each OFDM symbol period. Gets the N received symbols for the N subbands and gives the processor 1250 the received pilot symbols for channel estimation. The OFDM demodulator 1245 also receives frequency response estimates for the downlink from processor 1250 and performs data demodulation on the received data symbols to obtain the data symbol estimates (which are the transmitted data symbols). Is an estimate of), and gives the RX data processor 1255 a data symbol estimate. RX data processor 1255 demodulates (ie, symbol demaps), deinterleaves, decodes, and replays transmitted traffic data. Processing by the OFDM demodulator 1245 and RX data processor 1255 is complementary to processing by the OFDM modulator 1215 and TX data processor 1210 at access point 1200, respectively.

On the uplink, the TX data processor 1260 processes the traffic data and gives it a data symbol. The OFDM modulator 1265 receives and multiplexes a data symbol with a pilot symbol, performs OFDM modulation, and provides a stream of OFDM symbols. The pilot symbol is the pilot's transmission Can be transmitted over the sub-bands assigned to the terminal 1230, where the number of pilot sub-bands for the uplink is the same as the number of pilot sub-bands for the downlink. May be or may be different. Transmitter unit 1270 then receives and processes a stream of OFDM symbols to generate an uplink signal, which is transmitted to access point 1210 by antenna 1235. At access point 1210, the uplink signal from terminal 1230 is received by antenna 1225 and processed by receiver unit 1275 to obtain a sample. The OFDM demodulator then processes the sample and gives the received pilot and data symbol estimates for the uplink. The RX data processor 1285 processes the data symbol estimates and replays the traffic data transmitted by terminal 1235. Processor 1290 performs channel estimation for each active terminal transmitting over the uplink. Multiple terminals may transmit pilots on the uplink simultaneously on their respective set of assigned pilot subbands, where the set of pilot subbands can be interlaced.

Processors 1290 and 1250 manage operations at access points 1210 and terminal 1235, respectively (eg, control, coordinate, operate, etc.). Each processor 1290 and 1250 can be associated with a memory unit (not shown) that stores program code and data. Processors 1290 and 1250 can also perform operations to derive frequency response estimates and impulse response estimates for uplinks and downlinks, respectively.

For multiple access OFDM systems (eg, orthogonal frequency division multiple access (OFDMA) systems), multiple terminals can transmit simultaneously over the uplink. For such systems, the pilot subband can be shared between different terminals. Channel estimation techniques can be used in cases where the pilot subband for each terminal extends over the entire operating band (perhaps excluding the band edge). Such a pilot subband structure should be desirable to obtain frequency diversity for each terminal. The techniques described herein can be performed by a variety of means. For example, these techniques can be performed in hardware, in software, or in combination thereof. For hardware implementation, the processing units used for channel estimation are one or more application specific integrated circuits (ASICs), digital signal processors (DSPs). processors), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), processors, controllers, microcontrollers, It can be given in a microprocessor, other electronic units designed to perform the functions described herein, or a combination thereof. Using software, implementations can be performed through modules (eg, procedures, functions, and others) that perform the functions described herein. Software code can be stored in memory units and executed by processors 1290 and 1250.

What has been described above includes examples of one or more embodiments. This, of course, cannot describe all possible combinations of components or methods for the purposes of describing the above embodiments, but many additional combinations and replacements of the various embodiments are possible. Can be understood by those skilled in the art. Accordingly, the described embodiments are intended to include all such alternatives, modifications, and modifications contained within the spirit and scope of the appended claims. Moreover, to the extent that the term "includes" is used in either the detailed description or the claims, such terms are similarly in the sense of the term "comprising". Intended to be inclusive. The reason is that "equipped" is interpreted when it is adopted as a connecting word in the claims.

1200 ... wireless communication system, 1205 ... access point, 1230 ... terminal, 1225, 1235 ... antenna.