Resolving node identifier confusion

ES 2 397 800 T3

DESCRIPTION

Resolving a node identifier confusion

BACKGROUND

Field

This request refers in general to communications and more specifically, but not exclusively, to the resolution of confusion associated with communications nodes.

Introduction

Wireless communication systems are widely used to provide various types of communication (eg, voice, data, multimedia services, etc.) to multiple users. As the demand for high-speed and multimedia data services grows rapidly, implementing efficient, robust, and better-performing communications systems is a challenge.

To complement conventional mobile phone network base stations (eg macro cells), small coverage base stations (eg installed at a user's home) can be implemented to provide more robust internal wireless coverage to mobile units. Such small coverage base stations are generally known as access point base stations, home node Bs, or femtocells. Typically, such small coverage base stations are connected to the Internet and the mobile operator's network through a DSL router or cable modem.

In practice, there may be a relatively large number of base stations (eg, femto cells) implanted in a given area (eg, within the coverage area of ​​a given macro cell). In such a case, there is a need for efficient techniques to identify these base stations so that other nodes in the network can communicate with these base stations.

ABSTRACT

The invention is defined by independent claims 1, 6 and 7. The following is a summary of sample aspects of the invention. It should be understood that any reference to the term "aspects" in this document may refer to one or more aspects of the invention.

The invention relates in some respects to the resolution of confusion associated with node identifiers. For example, a limited number of node identifiers can be defined in a network such that more than one node (eg, one access point) on the network can be assigned the same identifier. Consequently, when an access terminal is handover from a source node to a destination node, there may be confusion as to the identity of the destination node. Several techniques to resolve such confusion are described in this document.

In some aspects, an access terminal to be handed over to a destination node can resolve confusion related to the destination node by acquiring a unique identifier associated with the destination node. In some implementations, the access terminal sends this unique identifier to a source node which initiates handover operations. In other implementations, the access terminal uses the unique identifier to initiate handover operations.

An access terminal can be configured to detect confusion. In some cases, an access terminal autonomously detects a confusion. For example, an access terminal can monitor identifiers associated with received signals and generate measurement notifications indicating that multiple nodes are using the same identifier.

As another example, a signal threshold can be assigned to a set of identifiers that may possibly be subject to confusion. This threshold can be used to initiate the acquisition of a more unique identifier or to initiate a confusion determination operation at a source node.

In some cases, an access terminal detects confusion in response to a request. For example, a source node may periodically send a message to an access terminal requesting that the access terminal send information related to a confusion through a measurement notification.

An access point can be configured to detect confusion. For example, an access point can detect confusion based on the discovery of neighboring nodes, on a destination node identified in a handover request, or on received configuration information. After detecting the confusion, the access point may send a message to an access terminal requesting that the access terminal acquire a unique identifier to resolve the confusion. In some cases, this message may instruct the access terminal to use a unique identifier to initiate handover operations.

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Confusion resolution can also be used when an access terminal directly accesses a destination node. For example, in case an access terminal establishes communication with a destination node before the destination node acquires resources for the access terminal, the access terminal may send a unique identifier for the source node to the destination node. In this way, the destination node acquires the appropriate resources from the source node even when a node identifier used by the source node is potentially conflicting.

The Ericsson document: Automatic neighbor cell configuration; 3GPP TSG-SA5 refers to automated neighbor cell relationships (ANRL). The Measurement Cell Identifier (MCI) is a level 1 identifier for a cell, which may not be unique in a network and can therefore be reused. The CIPL is another identifier (level 3), which is usually unique. The proposed ANRL procedure needs to be able to automatically determine new neighboring nodes and identify them. For this purpose, an eNodeB instructs a UE to perform measurements and notify a new MCI. If it is new, the eNodeB requests to retrieve the CIPL of the new eNodeB and notify it. Afterwards, the list of relationships between neighboring nodes is updated and an X2 interface can be configured.

The Huawei document: Detection of conflicting cell identities; 3GPP TSG RAN 1 / VG3 Meeting # 57bis refers to the detection of conflicting cell identities. Global cell identities (GCI) and physical layer cell identities (PLCI) can be used for this purpose. A UE can detect, during a cell hunt, a conflict between PLCIs. You can then decode the GCI value to assess whether there are any conflicts.

The document “Qualcomm Europe: Inter-RAT / frequency Automatic Neighbor Relation Function; 3GPP TSG RAN2 # 60 refers to sending a message from cell A to mobile terminal and contains a physical CID. A message containing a global CID is then sent from the mobile terminal to cell A.

The document “T-Mobile: Automatic Neighbor Cell List Configuration - required Measurement and signaling support; 3GPP TSG-RAN 1 / VG3 Meeting # 57bis refers to the measurement of a signal strength in a UE and the notification of it to an LTE.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other sample aspects of the invention will be described in the detailed description, in the subsequent appended claims, and in the accompanying drawings, in which:

FIG. 1 is a simplified block diagram of various sample aspects of a communication system configured to resolve confusion.

FIG. 2 is a simplified diagram illustrating coverage areas for wireless communication.

FIG. 3 is a flow chart of various sample aspects of operations that can be carried out to specify the use of a second type of identifier.

FIG. 4 is a simplified block diagram of various sample aspects of components that can be used in communication nodes.

FIG. 5 is a flow chart of various sample aspects of operations that can be performed to determine whether to use a second type of identifier for communications with a node.

FIG. 6 is a flow chart of various sample aspects of operations that can be performed to determine whether to use a second type of identifier for communications with a node based on a list of identifiers.

FIG. 7 is a flow chart of various sample aspects of operations that can be carried out to resolve a confusion for a source node.

FIG. 8 is a flow chart of various sample aspects of operations that can be carried out to determine whether to request the acquisition of a second type of identifier.

FIG. 9A and 9B are a flow chart of various sample aspects of operations that can be performed to cause an access terminal to acquire a second type of identifier.

FIG. 10A and 10B are a flow chart of various sample aspects of operations that can be performed to cause an access terminal to acquire a second type of identifier.

FIG. 11 is a flow chart of various sample aspects of operations that can be carried out in conjunction with an access terminal detecting confusion.

FIG. 12 is a flow chart of various sample aspects of operations that can be carried out in conjunction with an access terminal detecting confusion.

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FIG. 13 is a flow chart of various sample aspects of operations that can be carried out in conjunction with an access terminal that provides confusion notification on request.

FIG. 14 is a simplified diagram of a wireless communication system.

FIG. 15 is a simplified diagram of a wireless communication system that includes femtonodes.

FIG. 16 is a simplified block diagram of various sample aspects of communication components.

FIG. 17-21 are simplified block diagrams of various sample aspects of apparatus configured to resolve confusion as described herein.

In accordance with common practice, the various features illustrated in the drawings may not be drawn to scale. Accordingly, the dimensions of the various features can be arbitrarily enlarged or reduced for clarity. Also, some of the drawings may be simplified for clarity. Therefore, the drawings may not illustrate all components of a given apparatus (eg, device) or procedure. Finally, similar reference numerals may be used to denote similar features throughout the specification and the figures.

DETAILED DESCRIPTION

FIG. 1 illustrates various nodes of a sample communication system 100 (eg, a part of a communication network). For illustrative purposes, various aspects of the invention will be described in the context of one or more access terminals, access points, and network nodes communicating with each other. However, it should be appreciated that the teachings in this document may be applied to other types of apparatus or to other similar apparatus referred to using other terminology (eg, base stations, user equipment, etc.).

The access points of the system 100 provide one or more services (for example, network connectivity) to one or more wireless terminals (for example, an access terminal 102) that may be installed in or that may roam an entire geographic area. associated. For example, at different times, the access terminal 102 may be connected to an access point 104, to any one of a set of access points 1 to N (represented by access points 106 and 108 and the ellipsis associated), or to an access point 110. Each of the access points 102 to 110 can communicate with one or more network nodes (represented, for convenience, by the network node 112) to facilitate area network connectivity extensive. Such network nodes may take various forms such as, for example, one or more core and / or radio network entities (for example, a configuration manager, a mobility management entity or some other suitable network entity).

Each access point in system 100 is assigned a first type of identifier, referred to herein as a node identifier. In various implementations, such an identifier may comprise, for example, a physical cell identifier (PCID), a pseudo-random number offset (PN), or a pilot acquisition. Typically, a fixed number (for example, 504) of node identifiers is defined in a given system. In such a case, confusion can occur when the number of access points exceeds the number of node identifiers. FIG. 1 illustrates a simple example of this case, where access point 106 and access point 110 are both assigned identifier 1.

As access terminal 102 travels through system 100, access terminal 102 may handover from one access point (eg, access point 104) to another access point (eg, access point 110). The decision to hand over access terminal 102 to access point 110 may be based on whether access terminal 102 is receiving particularly strong signals from access point 110. In this case, the access terminal 102 identifies the signals from the access point 110 by means of the node identifier associated with (eg, included in) these signals. To perform a handover, various information held by the source access point 104 (the access point to which the access terminal is currently connected) is transferred to the destination access point 110. When there is no confusion, this can be accomplished by using the node identifier (identifier 1) associated with the access point 110. However, when there is confusion, as in the example of FIG. 1, access point 104 cannot determine whether the information should be sent to access point 106 or access point 110.

To resolve confusion like this, the access terminal 102 and / or the access point 104 are configured to detect the confusion and to determine a second type of identifier associated with the access point 110. In some aspects, the second type of identifier comprises a unique identifier. For example, the second type of identifier may be unique in a larger region with respect to the first type of identifier. In some implementations, the second type of identifier may be unique throughout an operator network. In various implementations, such a unique identifier may comprise, for example, a global cell identifier ("GCI"), an access node identifier ("ANID"), a sector identifier, an Internet protocol address. or some other identifier that uniquely identifies access point 110 on a network.

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In some implementations, the access terminal 102 includes a confusion detector 114 that can detect actual or potential confusion among the nodes of the system 100. After detecting a confusion, the access terminal 102 (eg, a unique identifier controller 116 ) can acquire the unique identifier. For example, access terminal 102 may monitor a signal that includes the unique identifier that is broadcast by access point 110. After detecting the confusion, the access terminal 102 may also inform the access point 104 of the confusion and / or the unique identifier.

In some implementations, access point 104 includes a confusion controller 118 that can detect actual or potential confusion between nodes in system 100. For example, confusion controller 118 can autonomously detect confusion or, upon receiving a confusion indication from access terminal 102, confusion controller 118 may perform additional steps to determine if there is a confusion. In the event that confusion is detected, access point 104 may request that access terminal 102 acquire the unique identifier.

Once the confusion is resolved as described above, the access point 104 (eg, a handover controller 120) can initiate handover operations based on the unique identifier. In this manner, the access terminal 102 can be efficiently handover to the desired destination access point. As will be described later, in some implementations, the access terminal 102 (eg, by operating a handover controller, not shown) can initiate handover operations based on the unique identifier (eg, once it resolves the confusion).

The confusion described above can occur in a network 200 such as that shown in FIG. 2, where some access points provide macro coverage and other access points provide smaller coverage. In this case, the macro coverage areas 204 may be provided, for example, by macro access points of a wide area cellular network such as a 3G network, commonly referred to as a macro cell network or a wide area network (WAN). Furthermore, smaller coverage areas 206 can be provided, for example, by access points of a network environment for residences or buildings, commonly referred to as a local area network (LAN). As an access terminal ("AT") roams such a network, the access terminal can receive service at certain locations via access points that provide macro coverage, while the access terminal can receive service. at other locations via access points that provide smaller area coverage. In some respects, smaller area coverage access points can be used to provide incremental capacity growth, coverage within buildings, and different services, resulting in a more robust user experience.

In the description of this document, a node (for example, an access point) that provides coverage over a relatively large area may be called a macro node, while a node that provides coverage for a relatively small area (for example, a residence) may be called the femtonode. It should be appreciated that the teachings in this document can be applied to nodes associated with other types of coverage areas. For example, a piconode can provide coverage in an area that is smaller than a macro area and larger than a femto area (for example, coverage in a shopping mall). In various applications, other terminology may be used to refer to a macro, femtonode, or other access point type nodes. For example, a macro node can be configured or named access node, base station, access point, eNodeB, macrocell, etc. Furthermore, a femtonode can be configured or referred to as a home NodeB, a home eNodeB, an access point base station, a femtocell, and so on. In some implementations, a node may be associated with (eg split into) one or more cells or sectors. A cell or sector associated with a macro-node, a femto-node or a piconode can be called a macro-cell, a femto-cell or a pico-cell, respectively.

In the example of FIG. 2, several tracking areas 202 (or routing areas or location areas) are defined, each of which includes several macro coverage areas 204. In this case, the coverage areas associated with tracking areas 202A, 202B and 202C they are outlined by broad lines, and the macro coverage areas 204 are represented by hexagons. As mentioned above, the tracking areas 202 may also include coverage femto areas 206. In this example, each of the coverage femto areas 206 (eg, coverage femto areas 206C) is illustrated within one or more macro coverage areas 204 (eg, macro coverage area 204B). However, it should be appreciated that a coverage femto area 206 may not be completely within a macro coverage area 204. In addition, one or more coverage pico areas or femto areas (not shown) may be defined within a given tracking area 202 or macro coverage area 204.

In a deployment (for example, a deployment in a densely populated urban area) where a large number of access points, such as femtonodes and piconodes, are located within a given area, two or more of these access points may have the same node identifier assigned. For example, in macro coverage area 204A, coverage femto areas 206A and 206D may be assigned the same identifier. In this case, node identifier confusion (eg PCID confusion) may occur as multiple neighboring nodes that are close to the service access point of an access terminal disclose the same node identifier. For example, in FIG. 1, the access points 106 and 110 may comprise femtonodes or piconodes that broadcast the "identifier 1" through respective pilot signals.

ES 2 397 800 T3 released. In addition, both access points may be close to the access point 104 (eg, a macro access point) that is currently serving the access terminal 102. In this case, the access point 104 may be aware of both access points. access 106 and 110 and therefore confusion can occur when a handover is indicated to the access point identified by identifier 1.

In general, the confusion resolution techniques described in this document can be applied to any type of node. However, in many implementations, the macro access points in a given area will be planned so that there is no confusion associated with a handover to a macro access point. In such cases, the confusion resolution techniques described in this document can be applied to any node on the network that is not a macro node. Such nodes that are not macrodes may include, for example, nodes that are implemented in an unplanned manner. As noted above, such non-macro nodes may include femtonodes (eg, user implanted) as well as operator implanted low power piconodes. Furthermore, as will be described in greater detail later, a node may be restricted in some way (eg, have restricted access). Therefore, the confusion resolution techniques described in this document can be applied to restricted nodes (eg, nodes associated with a closed group of subscribers).

Considering the general description provided above, various techniques that can be used to resolve confusion in accordance with the teachings of this document will be described with reference to FIGS. 3-13. By way of summary, FIG. 3 illustrates various components that can be used in an access point or access terminal, and the flow charts of FIGS. 4 to 13 refer to various confusion resolution techniques.

For illustrative purposes, the operations of FIGS. 4-13 (or any other operations described or shown in this document) are described as being carried out by specific components (eg, components of system 100 and / or the components shown in FIG. 3). However, it should be appreciated that these operations can be carried out by other types of components and can be carried out using a different number of components. It should also be appreciated that one or more of the operations described in this document may not be used in a given implementation.

FIG. 3 illustrates various sample components that can be incorporated into nodes, such as access terminal 102 and access point 104, to perform confusion resolution operations such as those described herein. The components described can also be incorporated into other nodes of a communication system. For example, other nodes in a system may include components similar to those described for access terminal 102 and access point 104 to provide similar functionality. A given node can contain one or more of the components described. For example, an access terminal may contain multiple transceiver components that allow the access terminal to operate on multiple frequencies and / or communicate through different technologies.

As shown in FIG. 3, access terminal 102 and access point 104 may include transceivers 302 and 304, respectively, to communicate with other nodes. Transceiver 302 includes a transmitter 306 for sending signals (eg, messages) and a receiver 308 for receiving messages (including, for example, searching for pilot signals). Transceiver 304 includes a transmitter 310 for sending signals and a receiver 312 for receiving signals.

Access terminal 102 and access point 104 also include other components that can be used in conjunction with confusion resolution operations such as those described in this document. For example, the access terminal 102 and the access point may include communication controllers 314 and 316, respectively, to manage communications with other nodes (eg, send and receive messages / indications) and to provide other related functionality described in this document. Access terminal 102 and / or access point 104 may include confusion detectors 318 and 320, respectively, to detect confusion and to provide other related functionality described herein. Access terminal 102 and / or access point 104 may include identifier controllers 322 and 324, respectively, to manage (eg, select, acquire, request, etc.) node identifiers and to provide other related functionality described in this document. Next, sample operations of the other components of FIG. 3.

For convenience, access point 102 and access terminal 104 are shown in FIG. 3 including components that can be used in the various examples described below in conjunction with FIGS. 4-13. In practice, one or more of the illustrated components may not be used in a given example. As an example, in some implementations the access terminal 102 may not comprise the confusion detector 318 and in some implementations the access point 104 may not include the confusion detector 320.

Referring now to FIGS. 4 and 5, in some aspects a confusion associated with the first type of identifier (for example, a PN offset, a PCID, etc.) can be resolved by specifying the use of a second type of identifier (for example, an ANID, a GCI, etc.) in conjunction with a handover or other transaction.

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This scheme can be used, for example, when an access terminal that is connected to a macro access point triggers a search for nearby femtonodes (eg, a home femtonode). When the access terminal detects a signal from a femtonode, the access terminal can obtain an identifier of the first type (for example, a pilot signal ID, a sector ID, a PCID, etc.) from the signal. . If the received signal strength is greater than a threshold value and / or the access terminal is authorized to access the discovered femtonode (for example, the access point is included in a preferred roaming list of the access terminal), the terminal You can add this access point to the active set for the access terminal.

The first access terminal to make an open path for this femtonode from the macro access point will establish a mapping between the identifier of the first type and the identifier of the second type (for example, an ANID, a GCI, etc.) in the macro point of access. In this case, after receiving the second type of identifier from the access terminal, the macro access point can initiate the discovery of neighboring nodes with that femtonode.

The presence of subsequent femtonodes with the same identifier of the first type in the macrocoverage will result in the macro access point determining that there are multiple access points using a common identifier of the first type (that is, detecting confusion regarding this identifier). In this case, the macro access point can discover the presence of these other femtonodes from, for example, the discovery of neighboring nodes or by receiving a message from an access terminal that has discovered the confusion. The macro access point can then always request a second type of identifier each time it receives a message (for example, an open path) that includes the identifier subject to confusion. After receiving the second type of identifier from an access terminal, the macro access point can initiate the discovery of neighboring nodes with that femtonode.

Also, as an optimization in some implementations, the access terminal can send messages with the second type of identifier by default. For example, the access terminal can always use the second type of identifier when sending an open route or other message for its home femtonode.

Referring initially to FIG. 4, as represented by block 402, an access point (for example, access point 104) receives a message from an access terminal, where the message is directed to a node (for example, a destination node such as access point 110) identified by a first node identifier. For example, as described above, the access terminal may receive an open path request that includes a PN offset or some other type of message that includes some other type of identifier. It should be appreciated that such a message can take various forms. For example, in various implementations, the message may comprise a message to configure resources for a handover, a handover request, an active set add request, interference management signaling, a signal strength measurement notification, or a message. to reserve at least one resource.

As represented by block 404, the access point determines whether another node is identified by the first node identifier. The access point can detect such confusion in several ways. For example, as described above, the access point can receive messages from one or more access terminals indicating the identifiers used by neighboring nodes. In some cases, the access point can perform neighbor node discovery and determine that two or more neighboring nodes are using the same identifier. In some cases, the access point may receive configuration information (for example, from a configuration manager as represented by node 112 of FIG. 1) that identifies the identifiers that are being used by neighboring nodes of the access point. . In some cases, the operation of block 404 may comprise determining whether the identifier is a list of identifiers maintained by the access point. As described in this document, this list of identifiers may comprise, for example, identifiers that are not guaranteed to be free from confusion, identifiers that are possibly subject to confusion, or identifiers that are subject to confusion. In some aspects, the list of identifiers may comprise a range of identifier values.

As represented by blocks 406 and 408, if no confusion is detected, the access point can perform the appropriate operation (eg, a handover operation) based on the first node identifier.

As represented by block 410, if confusion is detected, the access point sends a message to the access terminal specifying that the access terminal is to use the second node identifier (for example, an ANID) to establish communication with the node. Such a message can take several forms. For example, the message may comprise a rejection message (eg, an open path rejection) that instructs the access terminal to use a different identifier.

As represented by block 412, the access point may then receive a message from the access terminal that includes the second node identifier. The access point may carry out the appropriate operation (eg, a handover operation) based on the second node identifier. In some implementations, this may involve sending the message that includes the second node identifier to the destination node.

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In some aspects, the operations of FIG. 4 refer to reserving resources through a backhaul for a handover operation (for example, in conjunction with an add active set operation). Furthermore, since the nodes subject to confusion may be restricted in some respects (for example, having a restricted association or otherwise restricted as described later), these operations may also refer to reserving resources for restricted nodes.

FIG. 5 refers in some respects to specifying the use of a non-conflicting identifier to establish communications with a node. In some aspects, these operations may be complementary to some of the operations of FIG. Four.

As represented by block 502, an access terminal (eg, access terminal 102) chooses to transmit a message to a destination node identified by a first node identifier. As mentioned above in block 402, this message can be sent through an associated access point (eg, access point 104).

As represented by block 504, the access terminal determines whether another node can be identified by the first node identifier. This determination can be made in a number of ways. As described above, the access terminal may have sent a message to the access point 104 using the first node identifier and received a message from the access point 104 indicating that there is a confusion (and that specifies the use of a second node identifier). In some cases, this determination may involve attempting a communication with the destination node and receiving a message from a destination node indicating that the communication is not authorized. Such a reject message may be received because the access terminal context was sent to a node other than the intended destination node due to node identifier confusion. Furthermore, the access terminal can identify confusion based on signals it receives from neighboring access points indicating the identifiers used by those access points.

As represented by blocks 506 and 508, if no confusion is detected, the access terminal can use the first node identifier to establish communications with the destination node.

As represented by block 510, if confusion is detected, the access terminal can use the second node identifier to establish communications with the destination node.

In addition, as represented by block 512, the access terminal can be configured to use the second node identifier to establish communications with the destination node. For example, the access terminal can be configured in this way after the access terminal detects a confusion. Alternatively, as described in this document, the access terminal may send a second node identifier by default.

FIG. 6 refers in some respects to reserving a subset of the node identifier space (eg, the PCID space) for nodes that are not macrodes to simplify confusion resolution. In this way, a node that receives an identifier from the subset can easily determine that confusion is possible or probable. In some implementations, the subset comprises a set of designated values ​​that is associated with access points that are not free from confusion. In some implementations, the subset comprises a set of designated values ​​that is associated with a closed subscriber group (eg, as described below). In some implementations, the subset comprises a set of designated values ​​that is associated with access points of at least one designated type (eg, a node type). Such designated type may refer to, for example, one or more of the following: a transmit power, a coverage area, or retransmission capabilities.

As represented by block 602, an access terminal (eg, access terminal 102) receives a list of node identifiers. This list may comprise, for example, the subset of node identifiers described above. In some implementations, this list may be received from a service access point (eg, access point 104) that publishes the list. In some implementations, a target access point or some other access point (for example, through information from a list of neighboring nodes) may disclose an indication that the second type of identifier is to be used (for example, a GCI) when accessing the destination access point. In some implementations, this list may be received from a configuration manager (eg, network node 112) that keeps track of the reserved set of nodes that are assigned a list identifier.

As represented by block 604, the access terminal determines a first identifier to communicate with the destination access point. For example, as described in this document, an identifier may be received through a pilot signal or some other suitable signal.

As represented by block 606, the access terminal can determine (eg, autonomously) whether to use a second identifier (eg, a GCI) to establish communications with the access point. In some aspects, this determination may be based on the first identifier (eg, determining the type of the first identifier). For example, if the identifier obtained in block 604 is in 8

ES 2 397 800 T3 list obtained in block 602, the access terminal can acquire the second identifier. In this case, the acquisition of the second identifier may comprise monitoring other signals (from the destination access point) that contain the second identifier. As an example, the destination access point may broadcast the second identifier at intervals that are less frequent than the intervals at which the destination access point broadcasts a first identifier.

As represented by block 608, the access terminal may transmit a message comprising the second identifier to establish communications with the destination access point. This message can take various forms in various scenarios. For example, the message may comprise a signal strength measurement message, a radio resource notification, or a handover request. In a typical implementation, the access terminal (for example, the access terminal 102) includes the associated PCID and GCI values ​​in a measurement notification that the access terminal sends to its service access point (for example, the access 104). Furthermore, as described below in relation to FIG. 7, under certain circumstances the access terminal can send this information to the destination access point.

As represented by block 610, upon receiving this information, the serving access point can initiate a handover procedure using the GCI value. Consequently, the service access point will configure the resources in the destination cell and send a handover command to the access terminal.

FIG. 7 refers in some respects to selecting an identifier to be provided to a destination access point, where the identifier is associated with a source access point. For example, the access terminal can use the GCI of the source access point in case the access terminal accesses the destination access point directly, without prior handover preparation. In this case, the access terminal may include the GCI of the source access point when accessing the destination access point. This allows the destination access point to resolve any confusion about the identity of the source access point. The destination access points can then extract the content for the access terminal from the appropriate source access point and complete the handover. These operations are described in blocks 702 to 706 of FIG. 7.

As represented by block 702, the access terminal selects the identifier (eg, a GCI) from a set of identifiers (eg, a first identifier such as a PCID and a second identifier such as a GCI) associated with it. to a destination access point (for example, access point 110). In some aspects, the selection of the second identifier may be based on whether the first identifier is in a received list of identifiers (e.g., designated as not free of confusion, based on the node type of an access point, etc.) of similarly to that described above in relation to FIG. 6. As mentioned above, in some respects the selection of the second identifier may be based on a loss of communication with a source access point (eg, access point 104).

As represented by block 704, the access terminal transmits the selected identifier to the destination access point when it establishes communication with the destination access point. For example, the access terminal may include the GCI of the source access point in a connection request message.

As represented by block 706, the source access point may then use the selected identifier to communicate with and / or obtain configuration information from the source access point. In this way, the originating access point can obtain context information for the access terminal to complete the handover.

FIG. 8 refers in some respects to the operations that an access point and / or an access terminal can perform in conjunction with the detection and resolution of node identifier confusion. In some respects, these operations are complementary to the operations described above in relation to FIG. 5.

As represented by block 802, an access point (for example, access point 104) determines whether a plurality of nodes use the same identifier, where the identifier is of a first type (for example, a PCID) . As mentioned above, the access point can detect such confusion based on measurement notifications, discovery of neighboring nodes, and received messages.

As represented by blocks 804 and 806, if no confusion is detected, the access point can proceed with normal operations. For example, the access point may determine whether to carry out a handover based on an identifier of the first type received through a measurement notification.

As represented by block 808, if confusion is detected, the access point may issue a request to obtain an identifier of the second type that is associated with the identifier of the first type subject to confusion. For example, if a confusing PCID was received through a measurement notification from an access terminal (eg, access terminal 102), the access point may send a request to the access terminal to acquire the GCI. associated with PCID. The access terminal can then acquire the GCI, for example, as described in this document.

As represented by block 810, the access point may then receive a response from the access terminal including the GCI. Since the confusion will be resolved next (for example, at point

ES 2 397 800 T3), at block 812 the handover operation can be initiated (eg, via the access point) using the received GCI.

FIG. 9A and 9B refer in some respects to the use of a threshold to initiate the acquisition of a unique identifier (eg, GCI). In some cases, an access terminal can autonomously determine when to acquire the unique identifier, that is, without being instructed to do so by another node (eg, an access point).

As represented by block 902, an access terminal may receive a defined set of identifiers of a first type (eg, the list of node identifiers described above). In some implementations, this information may be defined or provided by a service access point (eg, token controller 324) or some other node. For example, the service access point may identify all PCID identifiers that are or may be subject to confusion, and supply a list of these identifiers to the access terminal.

As represented by block 904, the access terminal may also receive a threshold associated with the defined set of identifiers. For example, this threshold may designate the threshold signal strength value for a received signal that initiates GCI acquisition by the access terminal. In some implementations, this threshold may be defined or provided by a service access point (eg, by a threshold controller 334) or some other node. For example, this threshold can be defined to be lower (eg, by a few dB) than the received signal strength threshold that initiates a handover operation. In some implementations, the threshold may be specified as a relative offset from a destination access point signal strength or as an absolute threshold for the carrier-to-interference (C / I) value of a destination access point.

As represented by block 906, at some point in time, the access terminal will receive a signal that is associated with an identifier of the first type. As represented by block 908, the access terminal (eg, a comparer 330) can determine if the received identifier is in the identifier list. In addition, the access terminal (eg, a signal processor 332, which may be implemented in or co-operate with the receiver 308) determines whether the received signal strength of the signal received by block 906 is greater than or equal to the threshold.

As represented by blocks 910 and 912, if the criteria in block 908 are not met, the access terminal can continue to monitor signals from neighboring access points.

As represented by block 914, if the criteria of block 908 are met, the access terminal acquires an identifier of the second type (eg, GCI) that is associated with the identifier received in block 906. As As described above, this may involve monitoring a broadcast signal with a specific periodicity.

As represented by block 916, the access terminal (for example, the notification generator 328) sends a message to the access point that includes the identifier acquired in blocks 906 and 910 and the received signal strength of a associated signal (eg, the signal received at block 906). This message can be sent just after the unique identifier is acquired at block 910 or at some other time. In some implementations, this information is sent in a measurement notification. For example, this notification can be sent once the received signal strength of a received signal (eg, from a destination access point) exceeds a handover threshold.

As represented by block 918, since any confusion will now be resolved, the access point (eg, handover controller 326) determines whether to initiate a handover operation based on the identifier and received signal strength. provided in this message. As described in this document, if a handover operation is indicated, the access point will use the unique identifier to prepare the destination access point and send a handover command to the access terminal.

In some aspects, the scheme of FIG. 9 can be advantageous in high mobility environments. For example, this scheme can provide faster handover since the GCI can be read before the signal strength of the destination access point is strong enough to require a handover.

FIG. 10A and 10B refer in some respects to a scheme in which an access terminal notifies an access point of the receipt of a signal that has exceeded a threshold (eg, the GCI threshold). In this case, the access point can determine if confusion is possible and, if so, instruct the access terminal to acquire a unique identifier (eg, the GCI). In this case, the operations of blocks 1002 to 1012 may be similar to the operations of blocks 902 to 912, respectively.

However, in block 1014, if the criteria are met in block 1010, the access terminal sends a message to the access point that includes the identifier acquired in block 1006 and the received signal strength of the associated signal. This message can be sent just after the identifier is acquired in the block

ES 2 397 800 T3

1006 or at some other time. In some implementations, this information is sent in a measurement notification.

As represented by block 1016, the access point determines whether the confusion is possibly based on the information received. For example, this determination can be based on whether multiple nodes use the same identifier. Furthermore, this determination may optionally be based on the received signal strength of any detected signal that includes this identifier.

As represented by blocks 1018 and 1020, if no confusion is detected, the access point can proceed with normal operations. For example, the access point may determine whether to carry out a handover based on an identifier of the first type received through a measurement notification.

As represented by block 1022, if confusion is detected, the access point sends a message to the access terminal requesting that the access terminal acquire the unique identifier (eg, the CGI) associated with the identifier subject to confusion. As represented by block 1024, the access terminal can then acquire the identifier as described herein and send the identifier to the access point (eg, via a measurement notification).

As represented by blocks 1026 and 1028, the access point thus resolves the confusion and determines whether to initiate a handover based on the unique identifier and received signal strength (for example, as described herein ).

FIG. 11 relates in some respects to collision detection (eg autonomous detection) by means of an access terminal. In particular, this scheme refers to an access terminal that provides a measurement report with collision information.

As represented by block 1102, an access terminal detects a collision for a given identifier of a first type. For example, based on the supervised pilots or other suitable signals, the access terminal can determine that multiple access points use the same PCID as described in this document.

As represented by block 1104, the access terminal may optionally acquire an identifier of the second type (eg, a GCI) associated with the identifier for which a collision has been indicated. Again, this operation can be carried out in the manner described above.

As represented by block 1106, the access terminal sends a measurement notification that includes multiple entries for the identifier for which a collision has been detected. For example, if two access terminals use a PCID value of 12, the metering report can include two different entries corresponding to a PCID value of 12. In addition, the measurement notification may optionally include the unique identifier (eg, the GCI) associated with each of these entries.

FIG. 12 relates in some respects to autonomous collision detection by means of an access terminal. In particular, this scheme refers to an access terminal that sends a measurement notification if it detects a collision.

As represented by block 1202, an access terminal detects a collision for a given identifier of a first type. As before, the access terminal can determine that multiple access points use the same PCID based on the supervised pilot signals or other suitable signals, as described in this document.

In some aspects, the detection of a collision may be indicated based on whether at least two nodes are currently using this same identifier or have recently used the same identifier. For example, a collision may be indicated if the access terminal is currently receiving pilot or sync signals from multiple access points using the same PCID. Furthermore, a collision may be indicated if the access terminal received pilot or sync signals from multiple access points in a defined period of time (eg the last 10 seconds). Under certain conditions, this time period can be set to zero (for example, for a very fast moving access terminal). Furthermore, a collision may be indicated if the access terminal received pilot or sync signals from multiple access points during a time period associated with a defined number of handovers (eg, the last four handovers). This latter scheme can advantageously allow slowly moving access terminals to send notifications to cover a desired geographic area. In other words, this scheme allows the detection of repeating node identifiers over a larger geographic area.

As represented by block 1204, the access terminal may optionally acquire an identifier of the second type (eg, a GCI) associated with the identifier for which a collision has been indicated. Again, this operation can be carried out in the manner described above.

ES 2 397 800 T3

As represented by block 1206, the access terminal sends a measurement notification if a collision was detected in block 1202. In addition, the measurement notification may optionally include the unique identifier (eg, the GCI) associated with each of these entries.

FIG. 13 refers in some respects to an access terminal that provides collision notification on request. As represented by block 1302, the access terminal receives a request for a collision notification. For example, the network may periodically request the access terminal to send a measurement notification with collision information. This request can specify one or more identifiers (for example, PCIDs) for which the collision information is requested. This identifier may be the identifier of the requesting node (eg, the service access point). Alternatively, this request may include a wildcard identifier, where the access terminal is requested to report all detected collisions. As represented by block 1304, the access terminal monitors signals from neighboring access points and detects collisions if appropriate (block 1306). As represented by block 1308, the access terminal sends a collision notification if a collision was detected in block 1306. In case the access terminal does not have any collision information, the access terminal may respond with a "no events" message or it may not provide any response. It should be appreciated that one or more of the operations of FIGS. 11 to 13 can be combined in various ways in different implementations.

As mentioned above, the teachings in this document can be implemented in a network that uses macro access points and femtonodes. FIG. 14 and 15 illustrate examples of how access points can be implemented in such a network. FIG. 14 illustrates, in a simplified manner, how cells 1402 (eg, macro cells 1402A through 1402G) of a wireless communication system 1400 can be served by corresponding access points 1404 (eg, access points 1404A through 1404G). In this case, macro cells 1402 may correspond to macro coverage areas 204 of FIG. 2. As shown in FIG. 14, access terminals 1406 (eg, access terminals 1406A through 1406L) may be dispersed at various locations throughout the system over time. Each access terminal 1406 can communicate with one or more access points 1404 on a forward link (FL) and / or a reverse link (RL) at any given time, depending on whether the access terminal 1406 is active and whether it is in a soft handoff, for example. By utilizing this cellular scheme, the wireless communication system 1400 can provide service to a large geographic region. For example, each of the macrocells 1402A through 1402G can cover a few blocks in a neighborhood or several square miles of a rural setting.

FIG. 15 illustrates an example of how one or more femtonodes can be implemented in a network environment (eg, the 1400 system). In the system 1500 of FIG. 15, multiple femtonodes 1510 (eg, femtonodes 1510A and 1510B) are installed in a relatively small area coverage network environment (eg, one or more user residences 1530). Each femtonode 1510 can be coupled to a wide area network 1540 (eg, the Internet) and a central mobile operator network 1550 via a DSL router, cable modem, wireless link, or other means of connectivity (not shown). .

The holder of a femtonode 1510 may subscribe to a mobile service such as, for example, the 3G mobile service, offered through the central mobile operator network 1550. In addition, an access terminal 1520 may be capable of operating both in macro-environments as in smaller area coverage network environments (eg residential). In other words, depending on the current location of the access terminal 1520, the access terminal 1520 may be served by a macrocell access point 1560 associated with the central mobile operator network 1550 or by any one of a set of femtonodes. 1510 (eg, femtonodes 1510A and 1510B residing in a corresponding user residence 1530). For example, when a subscriber is away from home, the subscriber can receive service through a standard macro access point (for example, the 1560 access point) and when the subscriber is near or at home, the subscriber can receive service. via a femtonode (for example, node 1510A). In this case, a 1510 femtonode may be backward compatible with legacy 1520 access terminals.

A femtonode 1510 can be implanted on a single frequency or, alternatively, on multiple frequencies. Depending on the particular configuration, the single frequency or one or more of the multiple frequencies may overlap with one or more frequencies used by a macro access point (eg, access point 1560).

In some aspects, an access terminal 1520 may be configured to connect to a preferred femtonode (eg, the home femtonode of access terminal 1520) whenever such connectivity is possible. For example, as long as the access terminal 1520A is in the user's residence 1530, it may be desirable for the access terminal 1520A to communicate only with the home femtodo 1510A or 1510B.

In some aspects, if access terminal 1520 operates on cellular macronetwork 1550 but does not reside in its most preferred network (for example, defined in a preferred roaming list), access terminal 1520 can continue to search for the most preferred network ( for example, preferred femtonode 1510) using best system reselection ("BSR"), This may involve periodically exploring available systems to determine if the best systems are currently available and subsequent tasks for association with such preferred systems. With the acquisition input, the access terminal 1520 can limit the search to specific bands and channels. By

For example, the search for the most preferred system may be repeated periodically. Upon discovery of a preferred femtonode 1510, access terminal 1520 selects the femtonode 1510 to associate with in its coverage area.

A femtonode may be limited in some respects. For example, a given femtonode can only provide certain services to certain access terminals. In implementations with a so-called restricted (or closed) association, a given access terminal can only be served by the macrocellular mobile network and a defined set of femtonodes (eg, the femtonodes 1510 residing in the residence 1530 of the corresponding user). In some implementations, a node may be restricted from providing, to at least one node, at least one of the following: signaling, data access, registration, paging, or services.

In some aspects, a restricted femtonode (which may also be referred to as a closed subscriber group home NodeB) is a node that provides service to a restricted provisioned set of access terminals. This set can be extended temporarily or permanently as needed. In some aspects, a closed subscriber group (CSG) can be defined as the set of access points (eg, femtonodes) that share a common access control list of access terminals. A channel in which all femtonodes (or all restricted femtonodes) in a region operate can be called a femtochannel.

Therefore, there can be several relationships between a given femtonode and a given access terminal. For example, from the perspective of an access terminal, an open femtonode can refer to a femtonode without restricted associations (eg, the femtonode allows access to any access terminal). A restricted femtonode can refer to a femtonode that is restricted in some way (for example, it has a restricted association and / or registration). A home femtodo may refer to a femtodo that the access terminal is authorized to access and operate (eg, permanent access is provided for a defined set of one or more access terminals). A guest femto node may refer to a femto node that an access terminal is temporarily authorized to access and operate. An external femtonode may refer to a femtonode that the access terminal is not authorized to access or operate, except perhaps in emergency situations (eg, 112 calls).

From the point of view of a restricted femtonode, a home access terminal may refer to an access terminal that is authorized to access the restricted femtonode (eg, the access terminal has permanent access to the femtonode). A guest access terminal may refer to an access terminal with restricted temporary access to the femtonode (eg, limited by a deadline, usage time, bytes, connection count, or some other criterion or criteria). An external access terminal may refer to an access terminal that does not have permission to access the restricted femtonode, except in emergency situations, for example calls to 112 (for example, an access terminal that does not have the credentials or permissions to register with restricted femtonode).

For convenience, various functionalities are described in this document in the context of a femtonode. However, it should be appreciated that a piconode can provide identical or similar functionality for a larger coverage area. For example, a piconode can be restricted, a home piconode can be defined for a given access terminal, and so on.

The teachings in this document can be implemented in various types of communication devices. In some aspects, the teachings of this document can be implemented in wireless devices that can be implemented in a multiple access communications system that can simultaneously support communications for multiple wireless access terminals. In this case, each terminal can communicate with one or more access points through transmissions on the forward link and the reverse link. Forward link (or downlink) refers to the communication link from the access points to the terminals, and the reverse link (or uplink) refers to the communication link from the terminals to the access points. This communication link can be established through a single input single output system, a multiple input multiple output (MIMO) system, or some other type of system.

For illustrative purposes, FIG. 16 describes sample communication components that can be used in a wireless device in the context of a MIMO 800 type system. System 1600 uses multiple (Nt) transmit antennas and multiple (Nr) receive antennas for data transmission. A MIMO channel formed by the Nt transmitting antennas and the Nr receiving antennas can be decomposed into independent Nschannels, which are also called spatial channels, where Ns <min {Nt, Nr}. Each of the Ns independent channels corresponds to a dimension. The MIMO system can provide better performance (eg, higher data throughput and / or higher reliability) by utilizing the additional dimensionalities created by multiple transmit and receive antennas.

The 1600 system can support time division duplexing (TDD) and frequency division duplexing (FDD). In a TDD system, the forward link and reverse link transmissions are in the same frequency region, so the reciprocity principle allows estimation of the forward link channel from the reverse link channel. This allows the access point to extract a transmit beamforming gain on the forward link when multiple antennas are available at the access point.

ES 2 397 800 T3

System 1600 includes a wireless device 1610 (eg, an access point) and a wireless device 1650 (eg, an access terminal). In device 1610, traffic data from a plurality of data streams is provided from a data source 1612 to a transmission data processor (TX) 1614.

In some aspects, each data stream is transmitted through a respective transmitting antenna. The TX data processor 1614 formats, encodes, and interleaves the traffic data for each data stream based on a particular encoding scheme selected for that data stream to provide encoded data.

The encoded data for each data stream can be multiplexed with pilot data using OFDM techniques. Pilot data is typically a known data pattern that is processed in a known way and can be used in the receiving system to estimate channel responses. The multiplexed pilot data and encoded data for each data stream are then modulated (e.g. mapped symbols) based on a particular modulation scheme (e.g. BPSK, QSPK, M-PSK, or M-QAM) selected for that data stream to provide modulation symbols. The data transfer rate, encoding, and modulation for each data stream can be determined by instructions carried out by a 1630 processor. A data memory 1632 can store program codes, data, and other information used by processor 1630 or other components of device 1610.

The modulation symbols for all data streams are then provided to a TX 1620 MIMO processor, which can further process the modulation symbols (eg, for OFDM). The TX MIMO processor 1620 then provides Nt modulation symbol streams to Nt transceivers ("XCVR") 1622A through 1622T. In some aspects, the MIMO TX 1620 processor applies beamforming weights to the symbols in the data streams and to the antenna from which the symbol is being transmitted.

Each 1622 transceiver receives and processes a respective symbol stream to provide one or more analog signals and further conditions (e.g., amplifies, filters, and upconverts) the analog signals to provide a modulated signal suitable for transmission over the channel. MIME. Nt modulated signals from transceivers 1622A through 1622T are then transmitted from Nt antennas 1624A through 1624T, respectively.

In device 1650, the transmitted modulated signals are received by Nr antennas 1652A through 1652R and the received signal from each antenna 1652 is provided to a respective transceiver ("XCVR") 1654A through 1654R. Each transceiver 1654 conditions (eg, filters, amplifies, and downconverts) a respective received signal, digitizes the conditioned signal to provide samples, and further processes the samples to provide a corresponding received symbol stream.

Next, a receive data processor ("RX") 1660 receives and processes the Nr symbol streams received from Nr receivers 1654 based on a particular receiver processing technique to provide Nt detected symbol streams. The RX 1660 data processor then demodulates, de-interleaves, and decodes each detected symbol stream to recover the traffic data for the data stream. The RX 1660 data processor processing is complementary to that performed by the TX 1620 MIMO processor and the TX 1614 data processor in the 1610 device.

A processor 1670 periodically determines which precoding matrix to use (described later). Processor 1670 formulates a reverse link message that comprises an array index portion and a range value portion. A data memory 1672 can store program codes, data, and other information used by the 1670 processor or other components of the 1650 device.

The reverse link message may comprise various types of information related to the communication link and / or the received data flow. The reverse link message is then processed by a TX data processor 1638, which also receives traffic data for a plurality of data streams from a data source 1636, is modulated by a modulator 1680, is conditioned by transceivers 1654A to 1654R and transmitted to the 1610 device.

In device 1610, modulated signals from mobile device 1650 are received by antennas 1624, conditioned by transceivers 1622, demodulated by a demodulator ("DESMOD") 1640, and processed by an RX data processor 1642 to extract the data. reverse link message transmitted by device 1650. The processor 1630 then determines which precoding matrix to use to determine the beamforming weights and then processes the extracted message.

FIG. 16 also illustrates that the communication components may include one or more components that carry out confusion control operations in the manner described herein. For example, a confusion control component 1690 may cooperate with processor 1630 and / or other components of device 1610 to send / receive signals to / from another device (eg, device 1650) in the manner described herein. . Also, a confusion control component 1692 may cooperate with processor 1670 and / or other components of device 1650 to send / receive signals to / from another device (eg, device 1610). It should be appreciated that for each device 1610 and 14

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1650, the functionality of two or more of the described components can be provided by a single component. For example, a single processing component can provide the functionality of the 1690 confusion control component and the 1630 processor, and a single processing component can provide the functionality of the 1692 confusion control component and the 1670 processor.

The teachings in this document can be incorporated into various types of communication systems and / or system components. In some aspects, the teachings in this document can be used in a multiple access system that can support communications with multiple users sharing available system resources (for example, specifying one or more of the bandwidth, transmission power , encoding, interlacing, etc.). For example, the teachings in this document can be applied to any one or combinations of the following technologies: code division multiple access systems (CDMA), multi-carrier CDMA (MCCDMA), broadband CDMA (“W-CDMA”), high-speed packet access systems (“HSPA”, “HSPA +”), systems time division multiple access (“TDMA”), frequency division multiple access (FDMA) systems, single carrier FDMA (SC-FDMA) systems, orthogonal frequency division multiple access (“OFDMA”) systems or other multiple access techniques. A wireless communication system that uses the teachings in this document may be designed to implement one or more standards, such as IS-95, cdma2000, IS-856, W-CDMA, TDSCDMA, and other standards. A CDMA network may implement radio technology such as Universal Terrestrial Radio Access ("UTRA"), cdma2000, or some other technology. UTRA includes W-CDMA and low-speed chip (“LCR”). Cdma2000 technology covers IS-2000, IS-95 and IS-856 standards. A TDMA network can implement radio technology such as the Global System for Mobile Communications (GSM). An OFDMA network can implement radio technology such as Evolved UTRA (E-UTRA), IEEE 802.11, IEEE 802.16, IEEE 802.20, Flash-OFDM®, etc. UTRA, E-UTRA and GSM are part of the Universal Mobile Telecommunications System (“UMTS”). The teachings in this document can be implemented in a 3GPP Long Term Evolution ("LTE") system, an Ultramobile Broadband ("UMB") system, and other types of systems. LTE is a version of UMTS that uses E-UTRA. Although certain aspects of the invention can be described using 3GPP terminology, it should be understood that the teachings of this document can be applied to 3GPP technology (Re199, Re15, Re16, Re17), as well as 3GPP2 technology (IxRTT, IxEV-DO ReIO, RevA, RevB) and other technologies.

The teachings in this document can be incorporated into (eg, implemented in or carried out by) a variety of apparatus (eg, nodes). In some aspects, a node (eg, a wireless node) implemented in accordance with the teachings of this document may comprise an access point or an access terminal.

For example, an access terminal can comprise, be implemented or known as a user equipment, a subscriber station, a subscriber unit, a mobile station, a mobile, a mobile node, a remote station, a remote terminal, a terminal user agent, user agent, user device, or other terminology. In some implementations, an access terminal may comprise a cellular phone, a cordless phone, a session initiation protocol ("SIP") phone, a wireless local loop station ("WLL"), a personal digital assistant (" PDA ”), a handheld device with wireless capability, or some other suitable processing device connected to a wireless modem. Accordingly, one or more aspects described in this document may be incorporated into a telephone (eg, a cell phone or a smartphone), a computer (eg, a laptop), a portable communications device, a portable computing device. (for example, a personal data assistant), an entertainment device (for example, a music device, a video device or a satellite radio), a global positioning system device or any other suitable device that is configured to communicate over a wireless medium.

An access point can comprise, be implemented or known as a NodeB, an eNodeB, a radio network controller ("RNC"), a base station ("BS"), a radio base station (RBS "), a controller base station ("BSC"), a base transceiver station (BTS), a function transceiver (TF), a radio transceiver, a radio router, a Basic Service Set (BSS), an Extended Service Set (ESS ) or by other similar terminology.

In some aspects, a node (eg, an access point) may comprise an access node for a communication system. Such an access node can provide, for example, connectivity to or to a network (eg, a wide area network such as the Internet or a cellular network) via a wired or wireless communication link to the network. Consequently, an access node can allow another node (eg, an access terminal) to access a network or some other functionality. Furthermore, it should be appreciated that one or both of the nodes may be portable or, in some cases, relatively non-portable.

Furthermore, it should be appreciated that a wireless node may be capable of transmitting and / or receiving information non-wirelessly (eg, through a wired connection). Thus, a receiver and transmitter such as those described herein may include appropriate communication interface components (eg, electrical or optical interface components) for communicating over a non-wireless medium.

ES 2 397 800 T3

A wireless node may communicate over one or more wireless communication links that are based on or otherwise support any suitable wireless communication technology. For example, in some aspects, a wireless node may be associated with a network. In some aspects, the network may comprise a local area network or a wide area network. A wireless device may support or otherwise utilize one or more of a variety of wireless communication technologies, protocols, or standards such as those described in this document (e.g., CdMa, TDMA, OFDM, OFDMA, WiMAX, Wi-Fi, etc.). Also, a wireless node may support or otherwise utilize one or more of a variety of corresponding modulation or multiplexing schemes. A wireless node can therefore include appropriate components (eg, air interfaces) for establishing and communicating over one or more wireless communication links using prior technologies or other wireless communication technologies. For example, a wireless node may comprise a wireless transceiver with associated transmitter and receiver components that may include various components (eg, signal generators and signal processors) that facilitate communication over a wireless medium.

The components described in this document can be implemented in various ways. Referring to FIGS. 17-21, the 1700, 1800, 1900, 2000, and 2100 apparatuses are represented as a series of interrelated functional blocks. In some aspects, the functionality of these blocks can be implemented as a processing system that includes one or more processor components. In some aspects, the functionality of these blocks can be implemented using, for example, at least a part of one or more integrated circuits (for example, an ASIC). As described in this document, an integrated circuit can include a processor, software, other related components, or some combination thereof. The functionality of these blocks can also be implemented in some other way described in this document. In some aspects, one or more of the discontinuous blocks of FIGS. 17 to 21 are optional.

Apparatus 1700, 1800, 1900, 2000, and 2100 can include one or more modules that can perform one or more of the functions described above in relation to various figures. For example, a receiving means 1702, a message receiving means 1806, a request receiving means 1906, a signal receiving means 2012 or a receiving means 2108 may correspond, for example, to a receiver and / or a communications controller such as those described in this document. An identification determination means 1704 or an identical identifier determination means 1902 may correspond, for example, to a confusion detector as described in this document. A message sending means 1706, an identifier sending means 1802, an identifier definition means 1808, an identifier determination means 1908, a type determination means 2004, a second identifier determination means 2006 or a Identifier selection means 2104 may correspond, for example, to an identifier controller as described in this document. A transmission medium 1706 or a transmission medium 2008 may correspond, for example, to a transmitter and / or a communications controller such as those described in this document. A threshold sending means 1804 or a threshold setting means 1810 may correspond, for example, to a threshold controller as described herein. A notification sending means 1904 may correspond, for example, to a notification generator as described in this document. A first means of determining identifiers 2002, a means of using identifiers 2010, a communication means 2102 or a transmission means 2106 may correspond, for example, to a communication controller such as that described in this document. A means for determining signal intensity 2014 may correspond, for example, to a signal processor and / or receiver such as those described in this document.

Those skilled in the art will understand that information and signals can be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols and pieces of information that may have been referred to throughout the above description may be represented by voltages, currents, electromagnetic waves, particles or magnetic fields, particles or optical fields or any combination thereof.

Those skilled in the art will further appreciate that any of the various illustrative logic blocks, modules, processors, media, circuits, and algorithm steps described in connection with the aspects disclosed herein may be implemented as electronic hardware (e.g., an implementation digital, an analog implementation, or a combination of the two, which can be designed using source encoding or some other technique), various forms of program or design code incorporating instructions (which may be referred to in this document, for convenience, as software or "software module"), or combinations thereof. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been generically described above with respect to their functionality. Whether such functionality is implemented as hardware or software depends on the particular application and the design constraints imposed on the overall system. Those skilled in the art may implement the described functionality in various ways for each particular application, but such implementation decisions should not be construed as departing from the scope of the present invention.

The various illustrative logic blocks, modules and circuits described in connection with the aspects disclosed in this document may be implemented in or carried out by an integrated circuit ("IC"), an access terminal, or an access point. The IC may comprise a general purpose processor, a 16 processor

ES 2 397 800 T3 digital signals (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, electrical components, optical components, mechanical components, or any combination thereof designed to perform the functions described in this document, and it can execute codes or instructions that reside on the CI, outside the CI, or both. A general purpose processor can be a microprocessor but, alternatively, the processor can be any conventional processor, controller, microcontroller, or state machine. A processor can also be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors together with a DSP core, or any other such configuration.

The functions described can be implemented in hardware, software, firmware or any combination thereof. If implemented in software, the functions can be stored in or transmitted through one or more instructions or code on a computer-readable medium. Computer-readable media includes both computer storage media and communication media, including any medium that facilitates the transfer of a computer program from one location to another. A storage medium can be any available medium that can be accessed by a computer. By way of example, and not by way of limitation, such computer-readable media may comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to transport or store desired program code in the form of instructions or data structures and can be accessed by a computer. Furthermore, any connection is appropriately referred to as a computer-readable medium. For example, if the software is transmitted 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 microwaves, then coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of medium. Discs, as used in this document, include compact discs (CDs), laser discs, optical discs, digital versatile discs (DVD), floppy discs, and blue-ray discs, where the discs normally reproduce data magnetically. as well as optically with laser. Combinations of the above should also be included within the scope of computer-readable media. In summary, it should be appreciated that a computer-readable medium can be implemented in any suitable computer program product.