European Patent Office - EP 2377347 B1

Note: Within nine months of the publication of the mention of the grant of the European patent in the European PatentBulletin, any person may give notice to the European Patent Office of opposition to that patent, in accordance with theImplementing Regulations. Notice of opposition shall not be deemed to have been filed until the opposition fee has beenpaid. (Art. 99(1) European Patent Convention).

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(12) EUROPEAN PATENT SPECIFICATION

(45) Date of publication and mention of the grant of the patent: 20.09.2017 Bulletin 2017/38

(21) Application number: 09799467.7

(22) Date of filing: 22.12.2009

(51) Int Cl.:H04W 36/00 (2009.01)

(86) International application number: PCT/US2009/069341

(87) International publication number: WO 2010/075474 (01.07.2010 Gazette 2010/26)

(54) HANDOVER CONTROL BASED ON CLOSED SUBSCRIBER GROUP SUBSCRIPTION INFORMATION

HANDOVER-STEUERUNG AUF DER BASIS VON SUBSKRIPTIONSINFORMATIONEN GESCHLOSSENER TEILNEHMERGRUPPEN

GESTION DE TRANSFERT SUR LA BASE D’INFORMATIONS D’ABONNEMENTS D’UN GROUPE D’ABONNÉS FERMÉ

(84) Designated Contracting States: AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO SE SI SK SM TR

(30) Priority: 23.12.2008 US 140584 P18.12.2009 US 642292

(43) Date of publication of application: 19.10.2011 Bulletin 2011/42

(73) Proprietor: QUALCOMM IncorporatedSan Diego, CA 92121 (US)

(72) Inventor: HORN, Gavin B.San DiegoCalifornia 92121 (US)

(74) Representative: Wegner, HansBardehle Pagenberg Partnerschaft mbB Patentanwälte, Rechtsanwälte Prinzregentenplatz 781675 München (DE)

(56) References cited: WO-A1-2009/022976 US-A- 5 946 632

• PANASONIC: "UE access control in CSG cell" 3GPP DRAFT; R2-082238_UE ACCESS CONTROL IN CSG CELL, 3RD GENERATION PARTNERSHIP PROJECT (3GPP), MOBILE COMPETENCE CENTRE ; 650, ROUTE DES LUCIOLES ; F-06921 SOPHIA-ANTIPOLIS CEDEX ; FRANCE, vol. RAN WG2, no. Kansas City, USA; 20080429, 29 April 2008 (2008-04-29), XP050140005 [retrieved on 2008-04-29]

• NOKIA SIEMENS NETWORKS ET AL: "Impact on S1AP from HeNB GW concept" 3GPP DRAFT; R3-080465, 3RD GENERATION PARTNERSHIP PROJECT (3GPP), MOBILE COMPETENCE CENTRE ; 650, ROUTE DES LUCIOLES ; F-06921 SOPHIA-ANTIPOLIS CEDEX ; FRANCE, vol. RAN WG3, no. Sorrento, Italy; 20080218, 18 February 2008 (2008-02-18), XP050163662 [retrieved on 2008-02-18]

• VODAFONE GROUP: "Handover to CSG cells" 3GPP DRAFT; R2-072827, 3RD GENERATION PARTNERSHIP PROJECT (3GPP), MOBILE COMPETENCE CENTRE ; 650, ROUTE DES LUCIOLES ; F-06921 SOPHIA-ANTIPOLIS CEDEX ; FRANCE, vol. RAN WG2, no. Orlando, USA; 20070702, 2 July 2007 (2007-07-02), XP050135604 [retrieved on 2007-07-02]

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• QUALCOMM EUROPE: "Principles of Access Control for CSG Cells" 3GPP DRAFT; C1_083100, 3RD GENERATION PARTNERSHIP PROJECT (3GPP), MOBILE COMPETENCE CENTRE ; 650, ROUTE DES LUCIOLES ; F-06921 SOPHIA-ANTIPOLIS CEDEX ; FRANCE, no. Budapest, Hungary; 20080811, 11 August 2008 (2008-08-11), XP050308778 [retrieved on 2008-08-11]

• J. Carstens: "Architecture alternatives for LTE Femto GW Integration into Evolved Packet Core" 12 August 2008 (2008-08-12), XP002588392 Retrieved from the Internet: URL:http://priorartdatabase.com/IPCOM/0001 73330 [retrieved on 2010-06-23]

• ERICSSON: "CSG id in Initial UE message" 3GPP DRAFT; R3-083322, 3RD GENERATION PARTNERSHIP PROJECT (3GPP), MOBILE COMPETENCE CENTRE ; 650, ROUTE DES LUCIOLES ; F-06921 SOPHIA-ANTIPOLIS CEDEX ; FRANCE, no. Prague, Czech Republic; 20081105, 5 November 2008 (2008-11-05), XP050324540 [retrieved on 2008-11-05]

• NOKIA SIEMENS NETWORKS: "Clean up and update on security, mobility and DRX", 3GPP DRAFT; R2-074673 STAGE 2 UPDATE, 3RD GENERATION PARTNERSHIP PROJECT (3GPP), MOBILE COMPETENCE CENTRE ; 650, ROUTE DES LUCIOLES ; F-06921 SOPHIA-ANTIPOLIS CEDEX ; FRANCE, vol. RAN WG2, no. Jeju; 20071112, 12 November 2007 (2007-11-12), XP050137200, [retrieved on 2007-11-12]

• HUAWEI: "Adding 1bit Indicator into the ECGI", 3GPP DRAFT; R3-082526 ADDING 1BIT INDICATOR INTO THE ECGI_RV1, 3RD GENERATION PARTNERSHIP PROJECT (3GPP), MOBILE COMPETENCE CENTRE ; 650, ROUTE DES LUCIOLES ; F-06921 SOPHIA-ANTIPOLIS CEDEX ; FRANCE, no. Prague, Czech Republic; 20080924, 24 September 2008 (2008-09-24), XP050323812, [retrieved on 2008-09-24]

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Description

BACKGROUND

Field

[0001] This application relates generally to wirelesscommunication and more specifically, but not exclusive-ly, to handover control.

Introduction

[0002] A wireless communication network is deployedover a defined geographical area to provide various typesof services (e.g., voice, data, multimedia services, etc.)to users within that geographical area. In a typical imple-mentation, access points (e.g., corresponding to differentcells or sectors) are distributed throughout a network toprovide wireless connectivity for access terminals (e.g.,cell phones) that are operating within the geographicalarea served by the network. In general, at a given pointin time, the access terminal will be served by a given oneof these access points. As the access terminal roamsthroughout this geographical area, the access terminalmay move away from its serving access point and movecloser to another access point. In addition, signal condi-tions within a given cell may change, whereby an accessterminal may be better served by another access point.In these cases, the access terminal may be handed-overfrom its serving access point to be served by the otheraccess point to maintain mobility for the access terminal.[0003] An example of how the serving access point foran access terminal may be changed follows. The accessterminal may regularly perform radio frequency ("RF")measurements and determine that the signals being re-ceived from a neighbor access point (e.g., a so-calledtarget access point) are stronger than the signals beingreceived from the current serving access point by a cer-tain margin. As a result, the access terminal sends ameasurement report with this information to the network(e.g., to the serving access point). The serving accesspoint then performs backhaul communication with thetarget access point to negotiate resources for the accessterminal on the target access point. In addition, the serv-ing access point sends a handover command to the ac-cess terminal, wherein the handover command identifiesthe resources assigned to the access terminal on thetarget access point. Finally, the access terminal connectsto the target access point using these resources.[0004] In some networks, access points may be de-ployed whereby only specified subscribers are allowedto access a given set of one or more access points. Forexample, a closed subscriber group (CSG) may be de-fined such that only users that are subscribed with thatCSG are allowed to access an access point that is amember of the CSG. All other users in the network maythen be rejected if they attempt to access an access pointthat is a member of the CSG (an exception may be made

for emergency calls). Accordingly, there is a need foreffective mechanisms to control access to such accesspoints during handover.[0005] According to Panasonic, "UE access control inCSG cell", a source cell sends a handover request to amobility management entity (MME) via an S1 interface.The MME performs user equipment (UE) access acces-sibility check by using the handover request includingGCI of target cell and a whitelist. When the MME consid-ers that the UE is accessible to the target cell the MMEforwards the handover request to this target cell.[0006] According to Nokia Siemens Networks et. al.,"Impact on S1AP from HeNB GW concept", a macro eNBprovides a CSG-Id and a Global Cell Identifier as targetIDs in S1AP HO Required message which is sent to aMME. After a possible subscription check, the MME pro-vides the GCI in S1AP HO Request to the HNB-GW (fi-nally to the respective HeNB). The routing to the respec-tive Home eNB is performed in the HNB-GW from theGCI.[0007] Vodafone Group, "Handover to CSG cells", pro-poses that an eNodeB has means to ascertain whethera cell reported by a UE is a CSG cell or not. Accordingto Qualcomm Europe, "Principles of access control forCSG cells", CSG subscription information should be per-manently stored in a network element like a HSS, andretrieved by the MSE/VLR, SGSN, MME for access con-trol such as UE attach, service request and location/rout-ing/tracking area update procedures.[0008] According to Ericson, "CSG ID in initial UE mes-sage", when an eNB has received from a radio interfacea NAS message to be forwarded to an MME to which noUE-associated logical S1-connection for the US exists,the UE shall invoke the NAS transport procedure andsend the INITIAL UE MESSAGE to the MME includingthe NAS message as a NAS-PDU IE. NSN, "Clean upand update on security, mobility and DRX"describes ahandover procedure between two eNBs using a X2 in-terface.

SUMMARY

[0009] The above mentioned need is fulfilled by thesubject matter of the independent claims. Advantageousembodiments are contained in the dependent claims.[0010] A summary of sample aspects of the disclosurefollows. In the discussion herein, any reference to theterm aspects may refer to one or more aspects of thedisclosure.[0011] The disclosure relates in some aspects to con-trolling handover of an access terminal. For example,one or more nodes in a network may provide access con-trol for in-bound handovers to a CSG.[0012] In some cases, a source access point (e.g., acell of the source access point) provides access controlfor in-bound handover of an access terminal to a targetaccess point (e.g., a cell of the target access point) as-sociated with a CSG. In some aspects, the source access

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point controls access based on whether a CSG identifier(CSG ID) of the target access point is listed in the CSGsubscription information for the access terminal.[0013] In some cases, a network node (e.g., a mobilitymanager) provides access control for in-bound handoverto a target access point associated with a CSG. In someaspects, the network node controls access based onwhether the CSG ID of the target access point is in theCSG subscription information for the access terminal..In addition, the network node may provide the CSG sub-scription information to other nodes in the system (e.g.,source access points).[0014] In some cases, a target access point associatedwith a CSG provides access control for in-bound hando-ver to itself. In some aspects, the target access pointcontrols access based on whether the CSG ID of thetarget access point is in the CSG subscription informationfor the access terminal.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] These and other sample aspects of the disclo-sure will be described in the detailed description and theappended claims that follow, and in the accompanyingdrawings, wherein:

FIG. 1 is a simplified block diagram of several sampleaspects of a communication system adapted to con-trol handover of an access terminal;FIG. 2 is a flowchart of several sample aspects ofoperations that may be performed to control hando-ver at a source access point;FIG. 3 is a flowchart of several sample aspects ofoperations that may be performed to control hando-ver at a network node;FIG. 4 is a flowchart of several sample aspects ofoperations that may be performed to control hando-ver at a target access point;FIG. 5 is a simplified call flow illustrating several sam-ple aspects of operations that may be performed todirectly hand-over an access terminal from a sourceto a target;FIG. 6 is a simplified call flow illustrating several sam-ple aspects of operations that may be performed tohand-over an access terminal via a network node;FIG. 7 is a simplified block diagram of several sampleaspects of components that may be employed in acommunication node;FIG. 8 is a simplified diagram of a wireless commu-nication system;FIG. 9 is a simplified diagram of a wireless commu-nication system including femto nodes;FIG. 10 is a simplified diagram illustrating coverageareas for wireless communication;FIG. 11 is a simplified block diagram of several sam-ple aspects of communication components; andFIGS. 12 - 15 are simplified block diagrams of severalsample aspects of apparatuses configured to pro-

vide handover control as taught herein.

[0016] In accordance with common practice the vari-ous features illustrated in the drawings may not be drawnto scale. Accordingly, the dimensions of the various fea-tures may be arbitrarily expanded or reduced for clarity.In addition, some of the drawings may be simplified forclarity. Thus, the drawings may not depict all of the com-ponents of a given apparatus (e.g., device) or method.Finally, like reference numerals may be used to denotelike features throughout the specification and figures.

DETAILED DESCRIPTION

[0017] Various aspects of the disclosure are describedbelow. It should be apparent that the teachings hereinmay be embodied in a wide variety of forms and that anyspecific structure, function, or both being disclosed here-in is merely representative. Based on the teachings here-in one skilled in the art should appreciate that an aspectdisclosed herein may be implemented independently ofany other aspects and that two or more of these aspectsmay be combined in various ways. For example, an ap-paratus may be implemented or a method may be prac-ticed using any number of the aspects set forth herein.In addition, such an apparatus may be implemented orsuch a method may be practiced using other structure,functionality, or structure and functionality in addition toor other than one or more of the aspects set forth herein.Furthermore, an aspect may comprise at least one ele-ment of a claim.[0018] FIG. 1 illustrates several nodes of a samplecommunication system 100 (e.g., a portion of a commu-nication network). For illustration purposes, various as-pects of the disclosure will be described in the context ofone or more access terminals, access points, and net-work nodes that communicate with one another. It shouldbe appreciated, however, that the teachings herein maybe applicable to other types of apparatuses or other sim-ilar apparatuses that are referenced using other termi-nology. For example, in various implementations accesspoints may be referred to or implemented as base sta-tions, NodeBs, home NodeBs, Radio Network Control-lers (RNCs), eNodeBs, or home eNodeBs, while accessterminals may be referred to or implemented as userequipment or mobiles.[0019] Access points in the system 100 provide one ormore services (e.g., network connectivity) for one or morewireless terminals (e.g., access terminal 102) that maybe installed within or that may roam throughout a cover-age area of the system 100. For example, at variouspoints in time the access terminal 102 may connect toan access point 104 or an access point 106. Each of theaccess points 104 and 106 may communicate with oneor more network nodes (represented, for convenience,by network node 108) to facilitate wide area network con-nectivity. These network nodes may take various formssuch as, for example, one or more radio and/or core net-

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work entities. Thus, in various implementations the net-work node 108 may represent functionality such as atleast one of: network management (e.g., via an opera-tion, administration, management, and provisioning en-tity), call control, session management, mobility manage-ment, gateway functions, interworking functions, or someother suitable network functionality.[0020] One or more of the access point 104, the net-work node 108, and the access point 106 may provideaccess control for handover of the access terminal 102from the access point 104 to the access point 106. Insome cases, an access terminal may be handed-over toan access point associated with a wireless cell set. Ingeneral, a wireless cell set comprises a set of one ormore cells (e.g., at least one access point) where thereis a defined relationship specific to that set. An exampleof a wireless cell set is a CSG. For convenience, thediscussion that follows may simply refer to the term CSG,rather than the more general term wireless cell set. Itshould be appreciated, however, that the described con-cepts may be applicable to other types of defined sets orgroups of wireless cells or other similar entities.[0021] In some aspects, the access point 104, the net-work node 108, and the access point 106 may provideaccess control by determining whether a CSG ID asso-ciated with the access point 106 is listed in the CSG sub-scription information for the access terminal 102. If so,handover will be allowed since the access terminal 102has been subscribed to access the CSG associated withthe access point 106. Otherwise, the handover will notbe allowed.[0022] For illustration purposes, each of these nodesis illustrated as including handover access control com-ponents (i.e., handover access control functionality 110,112, and 114 and access terminal CSG subscription in-formation 116, 118, and 120). In practice, however, oneor more of these nodes may not include such function-ality. For example, in some implementations, only thenetwork node 108 and/or the target access point 106provide handover access control as taught herein.[0023] Sample operations of the system 100 will nowbe described in more detail in conjunction with the flow-charts of FIGS. 2 - 4. For convenience, the operations ofFIGS. 2 - 4 (or any other operations discussed or taughtherein) may be described as being performed by specificcomponents (e.g., the components shown in FIGS. 1 and7). It should be appreciated, however, that these opera-tions may be performed by other types of componentsand may be performed using a different number of com-ponents. It also should be appreciated that one or moreof the operations described herein may not be employedin a given implementation.[0024] FIG. 2 describes sample operations that maybe performed in conjunction with a source access pointcontrolling whether an access terminal being served bythat access point will be handed-over to a target accesspoint. Blocks 202 - 208 describe sample operations re-lating to configuring the source access point with CSG

subscription information for the access terminal. Blocks210 - 214 describe sample operations relating to hando-ver access control based on the CSG subscription infor-mation.[0025] As represented by block 202, at some point intime a connection is established for an access terminal(e.g., access terminal 102) at an access point (e.g., ac-cess point 104). For example, the access terminal maybe powered on when it is located within a cell of the ac-cess point, the access terminal may establish a connec-tion from idle mode, or the access terminal may be hand-ed-over to the access point from another access point.[0026] As represented by block 204, the access pointthen sends a message to the network to inform the net-work that the access terminal has established a connec-tion at the access point. For example, the access pointmay send an "initial UE message" to a mobility managersuch as a mobility management entity (MME) or a servingGPRS support node (SGSN).[0027] As represented by block 206, in response to thismessage, the network sends CSG subscription informa-tion for the access terminal to the access point. For ex-ample, the mobility manager may send an initial contextsetup request message to the access point that includesthe CSG subscription information. In some implementa-tions, this CSG subscription information may be includedin a handover restriction list information element (IE). Theaccess point receives the CSG subscription informationas represented by block 208.[0028] In some aspects, the CSG subscription infor-mation for a given access terminal identifies at least oneCSG at which that access terminal is allowed access(e.g., the CSG subscription information includes a list ofone or more CSG IDs). Thus, the CSG subscription in-formation may be referred to as an allowed CSG list (e.g.,from the perspective of the access terminal).[0029] As discussed above, an access terminal mayregularly perform RF measurements to determine thesignal conditions at its current cell and its neighboringcells. Consequently, the access terminal will occasionallysend measurement reports with this information to itsserving access point. In addition, in cases where detect-ed cells are associated with CSGs (e.g., the cell corre-sponds to a femto access point such as a home eNodeB),the access terminal may include the corresponding CSGIDs in neighbor relations messages sent to the servingaccess point.[0030] Thus, as represented by block 210, at somepoint in time the serving access point (e.g., access point104) will receive a measurement report that identifies atarget access point for handover of the access terminal.For example, when the signals being received at the ac-cess terminal from a neighbor access point are strongerthan the signals being received from the current servingaccess point (i.e., the source access point for the hando-ver) by a certain margin, the neighbor access point (e.g.,access point 106) may be designated as a target accesspoint for handover of the access terminal.

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[0031] As represented by block 212, the source accesspoint may determine whether to allow the access terminalto be handed-over to the target access point based onthe CSG subscription information for the access terminal.For example, the source access point may check if aCSG ID associated with the target access point (e.g., aCSG ID received during automatic neighbor relations op-erations) is listed in the CSG subscription information.[0032] If the source access point determines that thehandover should not be allowed, the source access pointwill not commence handover operations. Alternatively, ifthe source access point decides to allow the handover,the source access point may commence handover op-erations by sending a handover message to an appro-priate node as represented by block 214. Here, handovermay be accomplished in various ways in different imple-mentations.[0033] As described in more detail below in conjunctionwith FIG. 5, in some implementations the source accesspoint initiates handover via a message (e.g., a handoverrequest message) that is sent directly to the target accesspoint (e.g., via the backhaul). For example, the sourceaccess point may send such a message via the X2 pro-tocol (specified in 3GPP TS 36.423).[0034] As described in more detail below in conjunctionwith FIG. 6, in some implementations the source accesspoint initiates handover via a message (e.g., a handoverrequired message) that is sent to a network node (e.g.,a mobility manager). For example, the source accesspoint may send such a message via the S1 protocol(specified in 3GPP TS 36.413).[0035] In some implementations, the handover mes-sage sent at block 214 includes the CSG subscriptioninformation for the access terminal being handed-over.For example, the CSG subscription information may beincluded in a handover restriction list that is included inthe handover message.[0036] FIG. 3 describes sample operations that maybe performed by one or more network nodes (hereinafterreferred to, for convenience, as the network node) to con-trol whether an access terminal will be handed-over to atarget access point. In some implementations, the oper-ations of FIG. 3 may be performed by a mobility manager(e.g., an MME or SGSN).[0037] As represented by block 302, at some point intime the network node receives a message that indicatesthat an access terminal is being handed-over to a targetaccess points. This message may be received from dif-ferent nodes in different implementations. As describedin conjunction with block 214 above and FIG. 6 below, insome implementations the network node receives ahandover message (e.g., a handover required message)from the source access point. As described in more detailbelow in conjunction with FIG. 6, in some implementa-tions the network node receives a handover message(e.g., a handover request acknowledge message) fromthe target access point. As described in more detail belowin conjunction with FIG. 5, in some implementations the

network node receives a handover message (e.g., a pathswitch request message) from the target access point.[0038] As represented by blocks 304 and 306, the net-work node determines whether to allow the access ter-minal to be handed-over to the target access point basedon the CSG subscription information for the access ter-minal. For example, at block 304, the network node com-pares a CSG ID associated with the target access pointwith the CSG subscription information for the access ter-minal to determine whether the CSG ID is listed in theCSG subscription information. Then, at block 306, thenetwork node determines whether to allow the accessterminal to be handed-over to the target access pointbased on the comparison.[0039] If the network node determines that the hando-ver should not be allowed, the network node will terminatethe handover operations. For example, the network nodemay send a handover failure message to the node thatsent the message at block 302 (e.g., send a handoverpreparation failure message with the appropriate errorcode to the source access point).[0040] As represented by block 308, if the networknode decides to allow the handover, the network nodemay allow the handover operations to continue by send-ing a handover message to an appropriate node. In someaspects, this handover message comprises an indication(e.g., explicit or implicit) of the determination of block 306.[0041] In some aspects, the destination for this hando-ver message may depend on the type of message re-ceived at block 302. As described in FIG. 6, in implemen-tations where a handover required message was re-ceived from the source access point, the network nodemay send a handover request message to the target ac-cess point at block 308. Also as described in conjunctionwith FIG. 6 below, in implementations where a handoverrequest acknowledge message was received from thetarget access point and the network node performs ac-cess control upon receipt of this message, the networknode may send an appropriate message to the targetaccess point at block 308 that indicates whether thehandover is allowed. As described in FIG. 5, in imple-mentations where a path switch request message wasreceived from the target access point and the networknode performs access control upon receipt of this mes-sage, the network node may send a path switch requestacknowledgement message to the target access point atblock 308 that indicates whether the handover is allowed.[0042] FIG. 4 describes sample operations that maybe performed by a target access point to control whetheran access terminal will be handed-over to the target ac-cess point.[0043] As represented by block 402, the target accesspoint receives a handover request message. As dis-cussed herein, the target access point may receive thehandover request message from, for example, the sourceaccess point or a network node. In some aspects, thehandover request message may comprise CSG sub-scription information for the access terminal that is being

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handed-over. For example, the CSG subscription infor-mation may be included in a handover restriction list thatis included in the handover request message.[0044] As represented by block 404, the target accesspoint determines whether to allow the access terminal tobe handed-over based on the CSG subscription informa-tion for the access terminal. For example, the target ac-cess point may determine whether the CSG subscriptioninformation includes a CSG ID associated with the targetaccess point.[0045] If the target access point determines that thehandover should not be allowed, the target access pointwill terminate handover operations and send an appro-priate failure message to an appropriate node. Alterna-tively, if the target access point decides to allow thehandover, the target access point may send a handovermessage to an appropriate node as represented by block406. This message may explicitly or implicitly indicatethat the access terminal is being handed-over to the tar-get access point.[0046] In some aspects, the destination for this hando-ver message may depend on the type of message re-ceived at block 402. As described in FIG. 5, in implemen-tations where a handover request message is receivedfrom the source access point, the target access pointmay send a path switch request message to a networknode at block 406 to request that the handover be com-pleted. As described in FIG. 6, in implementations wherea handover request message was received from a net-work node, the target access point may send a handoverrequest acknowledge message to the network node atblock 406 to request that the handover be completed.[0047] In some aspects, the message sent at block 406may trigger handover access control at a network node.For example, as discussed above in conjunction withFIG. 3, upon receiving a handover message from a targetaccess point, a network node also may determine wheth-er to allow the handover.[0048] Accordingly, as represented by block 408, thetarget access point may subsequently receive an indica-tion of whether the handover is allowed from a networknode. As discussed herein, this message may take theform of, for example, a path switch request acknowledge-ment in the example of FIG. 5.[0049] With the above in mind, sample call flows as-sociated with handover access control will now be de-scribed in FIGS. 5 and 6. FIG. 5 describes sample callflow in an implementation where a source access pointand a target access point are able to directly communi-cate via, for example, an X2 protocol. FIG. 6 describessample call flow in an implementation where accesspoints communicate through a network node via, for ex-ample, an S1 protocol.[0050] For purposes of illustration, the examples ofFIGS. 5 and 6 describe implementations that are basedon LTE. Thus, the figures depict components such asuser equipment (UE), an eNodeB (eNB), an MME, a serv-ing gateway (SGW), and a packet data network gateway

(PGW). It should be appreciated, however, that the con-cepts taught herein may be applicable to other imple-mentations (e.g., a UMTS-based system, etc.).[0051] Referring initially to FIG. 5, at some point in timea UE sends a measurement report including a CSG IDof a target CSG cell to its serving eNB (e.g., a home eNB).This triggers a handover preparation message exchangebetween the source and the target.[0052] Before the source eNB performs a handover tothe target CSG cell, the source eNB optionally checks ifthe CSG ID of the target eNB (e.g., a home eNB) is inthe UE’s CSG subscription information (e.g., AllowedCSG list). The source eNB includes the Handover Re-striction List IE procedures in the Handover Requestmessage sent to the target eNB as part of the X2 hando-ver.[0053] Upon receiving the Handover Request, the tar-get eNB checks if its CSG ID is in the CSG subscriptioninformation for the UE (e.g., included in the HandoverRestriction List IE). If the UE is allowed to access theCSG cell, the target eNB responds with the HandoverRequest Acknowledge (Ack).[0054] Handover execution and handover completionoperations then commence. In some aspects these op-erations may include data transfers such as the forward-ing of data from the source to the target, the sending ofdownlink data from the target to the UE, and the sendingof uplink data from the UE to the PGW.[0055] The target eNB sends a Path Switch Requestmessage to inform the MME that the UE is changing cells.This message may include the Cell Global Identity of thetarget cell and the list of rejected EPS bearers. If appli-cable, the MME then determines that the SGW may con-tinue to serve the UE. The MME may also optionallycheck if the CSG ID of the target eNB is in the CSGsubscription information for the UE upon receiving thePath Switch Request message.[0056] The MME sends a User Plane Update Request(eNB address(es) and TEIDs for downlink user plane forthe accepted EPS bearers) message to the SGW. In caseany EPS bearers are to be released the MME triggers abearer release procedure. The SGW starts sendingdownlink packets to the target eNB using the newly re-ceived address and TEIDs. A User Plane Update Re-sponse message is sent back to the MME. To assist thereordering function in the target eNB, the SGW shall sendone or more "end marker" packets on the old path imme-diately after switching the path for each SAE bearer ofthe UE.[0057] The MME confirms the Path Switch Requestmessage with the Path Switch Request Acknowledge-ment (Ack) message. The MME may provide the eNBwith a Handover Restriction List (e.g., as discussed here-in).[0058] By sending a Release Resource message, thetarget eNB informs the source eNB that the handoverwas successful and triggers the release of resources.Depending on the RAN configuration, the eNB triggers

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the UE to initiate a Tracking Area Update procedure. RANfunctionality provides the ECM CONNECTED UE withthe trigger information.[0059] Referring now to FIG. 6, at some point in timea UE sends a measurement report to the source eNB(e.g., a home eNB).[0060] As discussed herein, the source eNB may per-form handover access control based on CSG subscriberinformation for the UE. If handover is allowed, the sourceeNB sends a Handover Required message to the MME(e.g., via S1).[0061] The MME may perform handover access con-trol based on CSG subscriber information for the UE astaught herein. If handover is not allowed, the MME re-sponds to the source eNB with a Handover PreparationFailure message with the appropriate error code (e.g.,not authorized for this CSG). If handover is allowed, theMME sends a Handover Request message to the targeteNB (e.g., a home eNB).[0062] The target eNB may perform handover accesscontrol based on CSG subscriber information for the UEas taught herein. If handover is allowed, the target eNBsends a Handover Request Acknowledge message tothe MME.[0063] The MME may perform handover access con-trol upon receipt of the Handover Request Acknowledgemessage. Again, this access control may be based onCSG subscriber information for the UE as taught herein.The MME may respond to the target eNB with an appro-priate message (not shown in FIG. 6) indicative of wheth-er handover is allowed. If handover is allowed, the MMEsends a Handover Command message to the sourceeNB to complete the handover.[0064] FIG. 7 illustrates several sample componentsthat may be incorporated into nodes such as an accesspoint 702 (e.g., corresponding to the access point 104 orthe access point 106) and a network node 704 (e.g., cor-responding to the network node 108) to perform hando-ver operations as taught herein. The described compo-nents also may be incorporated into other nodes in acommunication system. For example, other nodes in asystem may include components similar to those de-scribed for the access point 702 and the network node704 to provide similar functionality. A given node maycontain one or more of the described components. Forexample, an access point may contain multiple transceiv-er components that enable the access point to operateon multiple frequencies and/or communicate via differenttechnologies.[0065] As shown in FIG. 7, the access point 702 in-cludes a transceiver 706 for communicating with othernodes. The transceiver 706 includes a transmitter 708for sending signals (e.g., messages) and a receiver 710for receiving signals (e.g., messages).[0066] The access point 702 and the network node 704also include network interfaces 712 and 714, respective-ly, for communicating with one another or other networknodes. For example, the network interfaces 712 and 714

may be configured to communicate with one or more net-work nodes via a wired or wireless backhaul.[0067] The access point 702 and the network node 704also include other components that may be used in con-junction with handover operations as taught herein. Forexample, the access point 702 and the network node 704may include communication controllers 716 and 718, re-spectively, for managing communication with othernodes (e.g., sending and receiving handover messages,CSG information, handover indications, and other mes-sages or indications; and establishing connections) andfor providing other related functionality as taught herein.In addition, the access point 702 may include a handovercontroller 720 (e.g., corresponding in some aspects tothe functionality of block 110 and/or block 114 of FIG. 1)for managing mobility-related operations (e.g., determin-ing whether to allow handover) and for providing otherrelated functionality as taught herein. Similarly, the net-work node 704 may include a handover controller 722(e.g., corresponding in some aspects to the functionalityof block 112 of FIG. 1) for managing mobility-related op-erations (e.g., determining whether to allow handover,comparing CSG information, and sending CSG informa-tion) and for providing other related functionality as taughtherein.[0068] Also, in some implementations the componentsof FIG. 7 may be implemented in one or more processors(e.g., that uses and/or incorporates data memory). Forexample, the functionality of blocks 712, 716, and 720may be implemented by a processor or processors in anaccess point, while the functionality of blocks 714, 718,and 722 may be implemented by a processor or proces-sors in a network node.[0069] As discussed above, in some aspects the teach-ings herein may be employed in an environment that in-cludes macro scale coverage (e.g., a large area cellularnetwork such as a 3G network, typically referred to as amacro cell network or a WAN) and smaller scale cover-age (e.g., a residence-based or building-based networkenvironment, typically referred to as a LAN). As an ac-cess terminal (AT) moves through such an environment,the access terminal may be served in certain locationsby access points that provide macro coverage while theaccess terminal may be served at other locations by ac-cess points that provide smaller scale coverage. In someaspects, the smaller coverage nodes may be used toprovide incremental capacity growth, in-building cover-age, and different services (e.g., for a more robust userexperience).[0070] A node (e.g., an access point) that provides cov-erage over a relatively large area may be referred to asa macro access point while a node that provides cover-age over a relatively small area (e.g., a residence) maybe referred to as a femto access point. It should be ap-preciated that the teachings herein may be applicable tonodes associated with other types of coverage areas.For example, a pico access point may provide coverage(e.g., coverage within a commercial building) over an ar-

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ea that is smaller than a macro area and larger than afemto area. In various applications, other terminologymay be used to reference a macro access point, a femtoaccess point, or other access point-type nodes. For ex-ample, a macro access point may be configured or re-ferred to as an access node, base station, access point,eNodeB, macro cell, and so on. Also, a femto accesspoint may be configured or referred to as a Home NodeB,Home eNodeB, access point base station, femto cell, andso on. In some implementations, a node may be associ-ated with (e.g., divided into) one or more cells or sectors.A cell or sector associated with a macro access point, afemto access point, or a pico access point may be re-ferred to as a macro cell, a femto cell, or a pico cell,respectively.[0071] FIG. 8 illustrates a wireless communication sys-tem 800, configured to support a number of users, inwhich the teachings herein may be implemented. Thesystem 800 provides communication for multiple cells802, such as, for example, macro cells 802A - 802G, witheach cell being serviced by a corresponding access point804 (e.g., access points 804A - 804G). As shown in FIG.8, access terminals 806 (e.g., access terminals 806A -806L) may be dispersed at various locations throughoutthe system over time. Each access terminal 806 maycommunicate with one or more access points 804 on aforward link (FL) and/or a reverse link (RL) at a givenmoment, depending upon whether the access terminal806 is active and whether it is in soft handoff, for example.The wireless communication system 800 may provideservice over a large geographic region. For example,macro cells 802A - 802G may cover a few blocks in aneighborhood or several miles in rural environment.[0072] FIG. 9 illustrates an exemplary communicationsystem 900 where one or more femto access points aredeployed within a network environment. Specifically, thesystem 900 includes multiple femto access points 910(e.g., femto access points 910A and 910B) installed in arelatively small scale network environment (e.g., in oneor more user residences 930). Each femto access point910 may be coupled to a wide area network 940 (e.g.,the Internet) and a mobile operator core network 950 viaa DSL router, a cable modem, a wireless link, or otherconnectivity means (not shown). As will be discussedbelow, each femto access point 910 may be configuredto serve associated access terminals 920 (e.g., accessterminal 920A) and, optionally, other (e.g., hybrid or alien)access terminals 920 (e.g., access terminal 920B). Inother words, access to femto access points 910 may berestricted whereby a given access terminal 920 may beserved by a set of designated (e.g., home) femto accesspoint(s) 910 but may not be served by any non-designat-ed femto access points 910 (e.g., a neighbor’s femto ac-cess point 910).[0073] FIG. 10 illustrates an example of a coveragemap 1000 where several tracking areas 1002 (or routingareas or location areas) are defined, each of which in-cludes several macro coverage areas 1004. Here, areas

of coverage associated with tracking areas 1002A,1002B, and 1002C are delineated by the wide lines andthe macro coverage areas 1004 are represented by thelarger hexagons. The tracking areas 1002 also includefemto coverage areas 1006. In this example, each of thefemto coverage areas 1006 (e.g., femto coverage areas1006B and 1006C) is depicted within one or more macrocoverage areas 1004 (e.g., macro coverage areas 1004Aand 1004B). It should be appreciated, however, thatsome or all of a femto coverage area 1006 may not liewithin a macro coverage area 1004. In practice, a largenumber of femto coverage areas 1006 (e.g., femto cov-erage areas 1006A and 1006D) may be defined within agiven tracking area 1002 or macro coverage area 1004.Also, one or more pico coverage areas (not shown) maybe defined within a given tracking area 1002 or macrocoverage area 1004.[0074] Referring again to FIG. 9, the owner of a femtoaccess point 910 may subscribe to mobile service, suchas, for example, 3G mobile service, offered through themobile operator core network 950. In addition, an accessterminal 920 may be capable of operating both in macroenvironments and in smaller scale (e.g., residential) net-work environments. In other words, depending on thecurrent location of the access terminal 920, the accessterminal 920 may be served by a macro cell access point960 associated with the mobile operator core network950 or by any one of a set of femto access points 910(e.g., the femto access points 910A and 910B that residewithin a corresponding user residence 930). For exam-ple, when a subscriber is outside his home, he is servedby a standard macro access point (e.g., access point960) and when the subscriber is at home, he is servedby a femto access point (e.g., access point 910A). Here,a femto access point 910 may be backward compatiblewith legacy access terminals 920.[0075] A femto access point 910 may be deployed ona single frequency or, in the alternative, on multiple fre-quencies. Depending on the particular configuration, thesingle frequency or one or more of the multiple frequen-cies may overlap with one or more frequencies used bya macro access point (e.g., access point 960).[0076] In some aspects, an access terminal 920 maybe configured to connect to a preferred femto accesspoint (e.g., the home femto access point of the accessterminal 920) whenever such connectivity is possible. Forexample, whenever the access terminal 920A is withinthe user’s residence 930, it may be desired that the ac-cess terminal 920A communicate only with the homefemto access point 910A or 910B.[0077] In some aspects, if the access terminal 920 op-erates within the macro cellular network 950 but is notresiding on its most preferred network (e.g., as definedin a preferred roaming list), the access terminal 920 maycontinue to search for the most preferred network (e.g.,the preferred femto access point 910) using a better sys-tem reselection (BSR), which may involve a periodicscanning of available systems to determine whether bet-

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ter systems are currently available, and subsequent ef-forts to associate with such preferred systems. With theacquisition entry, the access terminal 920 may limit thesearch for specific band and channel. For example, oneor more femto channels may be defined whereby all fem-to access points (or all restricted femto access points) ina region operate on the femto channel(s). The search forthe most preferred system may be repeated periodically.Upon discovery of a preferred femto access point 910,the access terminal 920 selects the femto access point910 for camping within its coverage area.[0078] A femto access point may be restricted in someaspects. For example, a given femto access point mayonly provide certain services to certain access terminals.In deployments with so-called restricted (or closed) as-sociation, a given access terminal may only be servedby the macro cell mobile network and a defined set offemto access points (e.g., the femto access points 910that reside within the corresponding user residence 930).In some implementations, a node may be restricted tonot provide, for at least one node, at least one of: sign-aling, data access, registration, paging, or service.[0079] In some aspects, a restricted femto access point(which may also be referred to as a closed subscribergroup Home NodeB) is one that provides service to arestricted provisioned set of access terminals. This setmay be temporarily or permanently extended as neces-sary. In some aspects, a closed subscriber group iden-tifies subscribers of an operator who are permitted toaccess one or more cells of a wireless network (e.g.,PLMN) but which have restricted access. In some as-pects, a closed subscriber group may be defined as theset of access points (e.g., femto access points) that sharea common access control list of access terminals.[0080] Various relationships may thus exist between agiven femto access point and a given access terminal.For example, from the perspective of an access terminal,an open femto access point may refer to a femto accesspoint with no restricted association (e.g., the femto ac-cess point allows access to any access terminal). A re-stricted femto access point may refer to a femto accesspoint that is restricted in some manner (e.g., restrictedfor association and/or registration). A home femto accesspoint may refer to a femto access point on which theaccess terminal is authorized to access and operate on(e.g., permanent access is provided for a defined set ofone or more access terminals). A hybrid (or guest) femtoaccess point may refer to a femto access point on whichan access terminal is temporarily authorized to accessor operate on. An alien femto access point may refer toa femto access point on which the access terminal is notauthorized to access or operate on, except for perhapsemergency situations (e.g., 911 calls).[0081] From a restricted femto access point perspec-tive, a home access terminal may refer to an access ter-minal that is authorized to access the restricted femtoaccess point (e.g., the access terminal has permanentaccess to the femto access point). A guest access ter-

minal may refer to an access terminal with temporaryaccess to the restricted femto access point (e.g., limitedbased on deadline, time of use, bytes, connection count,or some other criterion or criteria). An alien access ter-minal may refer to an access terminal that does not havepermission to access the restricted femto access point,except for perhaps emergency situations, for example,such as 911 calls (e.g., an access terminal that does nothave the credentials or permission to register with therestricted femto access point).[0082] For convenience, the disclosure herein de-scribes various functionality in the context of a femto ac-cess point. It should be appreciated, however, that a picoaccess point may provide the same or similar function-ality for a larger coverage area. For example, a pico ac-cess point may be restricted, a home pico access pointmay be defined for a given access terminal, and so on.[0083] The teachings herein may be employed in awireless multiple-access communication system that si-multaneously supports communication for multiple wire-less access terminals. Here, each terminal may commu-nicate with one or more access points via transmissionson the forward and reverse links. The forward link (ordownlink) refers to the communication link from the ac-cess points to the terminals, and the reverse link (or up-link) refers to the communication link from the terminalsto the access points. This communication link may beestablished via a single-in-single-out system, a multiple-in-multiple-out (MIMO) system, or some other type of sys-tem.[0084] A MIMO system employs multiple (NT) transmitantennas and multiple (NR) receive antennas for datatransmission. A MIMO channel formed by the NT transmitand NR receive antennas may be decomposed into NSindependent channels, which are also referred to as spa-tial channels, where NS ≤ min {NT, NR}. Each of the NSindependent channels corresponds to a dimension. TheMIMO system may provide improved performance (e.g.,higher throughput and/or greater reliability) if the addi-tional dimensionalities created by the multiple transmitand receive antennas are utilized.[0085] A MIMO system may support time division du-plex (TDD) and frequency division duplex (FDD). In aTDD system, the forward and reverse link transmissionsare on the same frequency region so that the reciprocityprinciple allows the estimation of the forward link channelfrom the reverse link channel. This enables the accesspoint to extract transmit beam-forming gain on the for-ward link when multiple antennas are available at theaccess point.[0086] FIG. 11 illustrates a wireless device 1110 (e.g.,an access point) and a wireless device 1150 (e.g., anaccess terminal) of a sample MIMO system 1100. At thedevice 1110, traffic data for a number of data streams isprovided from a data source 1112 to a transmit (TX) dataprocessor 1114. Each data stream may then be trans-mitted over a respective transmit antenna.[0087] The TX data processor 1114 formats, codes,

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and interleaves the traffic data for each data streambased on a particular coding scheme selected for thatdata stream to provide coded data. The coded data foreach data stream may be multiplexed with pilot data usingOFDM techniques. The pilot data is typically a knowndata pattern that is processed in a known manner andmay be used at the receiver system to estimate the chan-nel response. The multiplexed pilot and coded data foreach data stream is then modulated (i.e., symbolmapped) based on a particular modulation scheme (e.g.,BPSK, QSPK, M-PSK, or M-QAM) selected for that datastream to provide modulation symbols. The data rate,coding, and modulation for each data stream may bedetermined by instructions performed by a processor1130. A data memory 1132 may store program code,data, and other information used by the processor 1130or other components of the device 1110.[0088] The modulation symbols for all data streamsare then provided to a TX MIMO processor 1120, whichmay further process the modulation symbols (e.g., forOFDM). The TX MIMO processor 1120 then provides NTmodulation symbol streams to NT transceivers (XCVR)1122A through 1122T. In some aspects, the TX MIMOprocessor 1120 applies beam-forming weights to thesymbols of the data streams and to the antenna fromwhich the symbol is being transmitted.[0089] Each transceiver 1122 receives and processesa respective symbol stream to provide one or more an-alog signals, and further conditions (e.g., amplifies, fil-ters, and upconverts) the analog signals to provide amodulated signal suitable for transmission over the MI-MO channel. NT modulated signals from transceivers1122A through 1122T are then transmitted from NT an-tennas 1124A through 1124T, respectively.[0090] At the device 1150, the transmitted modulatedsignals are received by NR antennas 1152A through1152R and the received signal from each antenna 1152is provided to a respective transceiver (XCVR) 1154Athrough 1154R. Each transceiver 1154 conditions (e.g.,filters, amplifies, and downconverts) a respective re-ceived signal, digitizes the conditioned signal to providesamples, and further processes the samples to providea corresponding "received" symbol stream.[0091] A receive (RX) data processor 1160 then re-ceives and processes the NR received symbol streamsfrom NR transceivers 1154 based on a particular receiverprocessing technique to provide NT "detected" symbolstreams. The RX data processor 1160 then demodulates,deinterleaves, and decodes each detected symbolstream to recover the traffic data for the data stream. Theprocessing by the RX data processor 1160 is comple-mentary to that performed by the TX MIMO processor1120 and the TX data processor 1114 at the device 1110.[0092] A processor 1170 periodically determineswhich pre-coding matrix to use (discussed below). Theprocessor 1170 formulates a reverse link message com-prising a matrix index portion and a rank value portion.A data memory 1172 may store program code, data, and

other information used by the processor 1170 or othercomponents of the device 1150.[0093] The reverse link message may comprise vari-ous types of information regarding the communicationlink and/or the received data stream. The reverse linkmessage is then processed by a TX data processor 1138,which also receives traffic data for a number of datastreams from a data source 1136, modulated by a mod-ulator 1180, conditioned by the transceivers 1154Athrough 1154R, and transmitted back to the device 1110.[0094] At the device 1110, the modulated signals fromthe device 1150 are received by the antennas 1124, con-ditioned by the transceivers 1122, demodulated by a de-modulator (DEMOD) 1140, and processed by a RX dataprocessor 1142 to extract the reverse link message trans-mitted by the device 1150. The processor 1130 then de-termines which pre-coding matrix to use for determiningthe beam-forming weights then processes the extractedmessage.[0095] FIG. 11 also illustrates that the communicationcomponents may include one or more components thatperform handover control operations as taught herein.For example, a handover control component 1190 maycooperate with the processor 1130 and/or other compo-nents of the device 1110 to send/receive signals to/fromanother device (e.g., device 1150) as taught herein. Sim-ilarly, a handover control component 1192 may cooper-ate with the processor 1170 and/or other components ofthe device 1150 to send/receive signals to/from anotherdevice (e.g., device 1110). It should be appreciated thatfor each device 1110 and 1150 the functionality of twoor more of the described components may be providedby a single component. For example, a single processingcomponent may provide the functionality of the handovercontrol component 1190 and the processor 1130 and asingle processing component may provide the function-ality of the handover control component 1192 and theprocessor 1170.[0096] The teachings herein may be incorporated intovarious types of communication systems and/or systemcomponents. In some aspects, the teachings herein maybe employed in a multiple-access system capable of sup-porting communication with multiple users by sharing theavailable system resources (e.g., by specifying one ormore of bandwidth, transmit power, coding, interleaving,and so on). For example, the teachings herein may beapplied to any one or combinations of the following tech-nologies: Code Division Multiple Access (CDMA) sys-tems, Multiple-Carrier CDMA (MCCDMA), WidebandCDMA (W-CDMA), High-Speed Packet Access (HSPA,HSPA+) systems, Time Division Multiple Access (TDMA)systems, Frequency Division Multiple Access (FDMA)systems, Single-Carrier FDMA (SC-FDMA) systems, Or-thogonal Frequency Division Multiple Access (OFDMA)systems, or other multiple access techniques. A wirelesscommunication system employing the teachings hereinmay be designed to implement one or more standards,such as IS-95, cdma2000, IS-856, W-CDMA, TDSCD-

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MA, and other standards. A CDMA network may imple-ment a radio technology such as Universal TerrestrialRadio Access (UTRA), cdma2000, or some other tech-nology. UTRA includes W-CDMA and Low Chip Rate(LCR). The cdma2000 technology covers IS-2000, IS-95and IS-856 standards. A TDMA network may implementa radio technology such as Global System for MobileCommunications (GSM). An OFDMA network may im-plement a 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 Uni-versal Mobile Telecommunication System (UMTS). Theteachings herein may be implemented in a 3GPP LongTerm Evolution (LTE) system, an Ultra-Mobile Broad-band (UMB) system, and other types of systems. LTE isa release of UMTS that uses E-UTRA. UTRA, E-UTRA,GSM, UMTS and LTE are described in documents froman organization named "3rd Generation PartnershipProject" (3GPP), while cdma2000 is described in docu-ments from an organization named "3rd Generation Part-nership Project 2" (3GPP2). Although certain aspects ofthe disclosure may be described using 3GPP terminolo-gy, it is to be understood that the teachings herein maybe applied to 3GPP (e.g., Re199, Re15, Re16, Re17)technology, as well as 3GPP2 (e.g., 1xRTT, 1xEV-DORelO, RevA, RevB) technology and other technologies.[0097] The teachings herein may be incorporated into(e.g., implemented within or performed by) a variety ofapparatuses (e.g., nodes). In some aspects, a node (e.g.,a wireless node) implemented in accordance with theteachings herein may comprise an access point or anaccess terminal.[0098] For example, an access terminal may comprise,be implemented as, or known as user equipment, a sub-scriber station, a subscriber unit, a mobile station, a mo-bile, a mobile node, a remote station, a remote terminal,a user terminal, a user agent, a user device, or someother terminology. In some implementations an accessterminal may comprise a cellular telephone, a cordlesstelephone, a session initiation protocol (SIP) phone, awireless local loop (WLL) station, a personal digital as-sistant (PDA), a handheld device having wireless con-nection capability, or some other suitable processing de-vice connected to a wireless modem. Accordingly, oneor more aspects taught herein may be incorporated intoa phone (e.g., a cellular phone or smart phone), a com-puter (e.g., a laptop), a portable communication device,a portable computing device (e.g., a personal data as-sistant), an entertainment device (e.g., a music device,a video device, or a satellite radio), a global positioningsystem device, or any other suitable device that is con-figured to communicate via a wireless medium.[0099] An access point may comprise, be implementedas, or known as a NodeB, an eNodeB, a radio networkcontroller (RNC), a base station (BS), a radio base station(RBS), a base station controller (BSC), a base transceiv-er station (BTS), a transceiver function (TF), a radio trans-ceiver, a radio router, a basic service set (BSS), an ex-

tended service set (ESS), a macro cell, a macro node, aHome eNB (HeNB), a femto cell, a femto node, a piconode, or some other similar terminology.[0100] In some aspects a node (e.g., an access point)may comprise an access node for a communication sys-tem. Such an access node may provide, for example,connectivity for or to a network (e.g., a wide area networksuch as the Internet or a cellular network) via a wired orwireless communication link to the network. Accordingly,an access node may enable another node (e.g., an ac-cess terminal) to access a network or some other func-tionality. In addition, it should be appreciated that one orboth of the nodes may be portable or, in some cases,relatively non-portable.[0101] Also, it should be appreciated that a wirelessnode may be capable of transmitting and/or receivinginformation in a non-wireless manner (e.g., via a wiredconnection). Thus, a receiver and a transmitter as dis-cussed herein may include appropriate communicationinterface components (e.g., electrical or optical interfacecomponents) to communicate via a non-wireless medi-um.[0102] A wireless node may communicate via one ormore wireless communication links that are based on orotherwise support any suitable wireless communicationtechnology. For example, in some aspects a wirelessnode may associate with a network. In some aspects thenetwork may comprise a local area network or a widearea network. A wireless device may support or other-wise use one or more of a variety of wireless communi-cation technologies, protocols, or standards such asthose discussed herein (e.g., CDMA, TDMA, OFDM,OFDMA, WiMAX, Wi-Fi, and so on). Similarly, a wirelessnode may support or otherwise use one or more of avariety of corresponding modulation or multiplexingschemes. A wireless node may thus include appropriatecomponents (e.g., air interfaces) to establish and com-municate via one or more wireless communication linksusing the above or other wireless communication tech-nologies. For example, a wireless node may comprise awireless transceiver with associated transmitter and re-ceiver components that may include various components(e.g., signal generators and signal processors) that facil-itate communication over a wireless medium.[0103] The functionality described herein (e.g., with re-gard to one or more of the accompanying figures) maycorrespond in some aspects to similarly designated"means for" functionality in the appended claims. Refer-ring to FIGS. 12, 13, 14, and 15, apparatuses 1200, 1300,1400, and 1500 are represented as a series of interre-lated functional modules. Here, a connection establish-ing module 1202 may correspond at least in some as-pects to, for example, a communication controller as dis-cussed herein. A CSG subscription information receivingmodule 1204 may correspond at least in some aspectsto, for example, a communication controller as discussedherein. A handover determining module 1206 may cor-respond at least in some aspects to, for example, a

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handover controller as discussed herein. A handover re-quest message sending module 1208 may correspondat least in some aspects to, for example, a communica-tion controller as discussed herein. A handover requiredmessage sending module 1210 may correspond at leastin some aspects to, for example, a communication con-troller as discussed herein. A handover request messagereceiving module 1302 may correspond at least in someaspects to, for example, a communication controller asdiscussed herein. A handover determining module 1304may correspond at least in some aspects to, for example,a handover controller as discussed herein. A handoverindication receiving module 1306 may correspond atleast in some aspects to, for example, a communicationcontroller as discussed herein. A handover message re-ceiving module 1402 may correspond at least in someaspects to, for example, a communication controller asdiscussed herein. A comparing module 1404 may corre-spond at least in some aspects to, for example, a hando-ver controller as discussed herein. A handover determin-ing module 1406 may correspond at least in some as-pects to, for example, a handover controller as discussedherein. A handover request message sending module1408 may correspond at least in some aspects to, forexample, a communication controller as discussed here-in. An indication sending module 1410 may correspondat least in some aspects to, for example, a communica-tion controller as discussed herein. A message receivingmodule 1502 may correspond at least in some aspectsto, for example, a communication controller as discussedherein. A CSG subscription information sending module1504 may correspond at least in some aspects to, forexample, a handover controller as discussed herein.[0104] The functionality of the modules of FIGS. 12 -15 may be implemented in various ways consistent withthe teachings herein. In some aspects the functionalityof these modules may be implemented as one or moreelectrical components. In some aspects the functionalityof these blocks may be implemented as a processingsystem including one or more processor components. Insome aspects the functionality of these modules may beimplemented using, for example, at least a portion of oneor more integrated circuits (e.g., an ASIC). As discussedherein, an integrated circuit may include a processor,software, other related components, or some combina-tion thereof. The functionality of these modules also maybe implemented in some other manner as taught herein.In some aspects one or more of any dashed blocks inFIGS. 12 - 15 are optional.[0105] It should be understood that any reference toan element herein using a designation such as "first,""second," and so forth does not generally limit the quan-tity or order of those elements. Rather, these designa-tions may be used herein as a convenient method of dis-tinguishing between two or more elements or instancesof an element. Thus, a reference to first and second el-ements does not mean that only two elements may beemployed there or that the first element must precede

the second element in some manner. Also, unless statedotherwise a set of elements may comprise one or moreelements. In addition, terminology of the form "at leastone of: A, B, or C" used in the description or the claimsmeans "A or B or C or any combination of these ele-ments."[0106] Those of skill in the art would understand thatinformation and signals may be represented using anyof a variety of different technologies and techniques. Forexample, data, instructions, commands, information, sig-nals, bits, symbols, and chips that may be referencedthroughout the above description may be represented byvoltages, currents, electromagnetic waves, magneticfields or particles, optical fields or particles, or any com-bination thereof.[0107] Those of skill would further appreciate that anyof the various illustrative logical blocks, modules, proc-essors, means, circuits, and algorithm steps describedin connection with the aspects disclosed herein may beimplemented as electronic hardware (e.g., a digital im-plementation, an analog implementation, or a combina-tion of the two, which may be designed using source cod-ing or some other technique), various forms of programor design code incorporating instructions (which may bereferred to herein, for convenience, as "software" or a"software module"), or combinations of both. To clearlyillustrate this interchangeability of hardware and soft-ware, various illustrative components, blocks, modules,circuits, and steps have been described above generallyin terms of their functionality. Whether such functionalityis implemented as hardware or software depends uponthe particular application and design constraints imposedon the overall system. Skilled artisans may implementthe described functionality in varying ways for each par-ticular application, but such implementation decisionsshould not be interpreted as causing a departure fromthe scope of the present disclosure.[0108] The various illustrative logical blocks, modules,and circuits described in connection with the aspects dis-closed herein may be implemented within or performedby an integrated circuit (IC), an access terminal, or anaccess point. The IC may comprise a general purposeprocessor, a digital signal processor (DSP), an applica-tion specific integrated circuit (ASIC), a field programma-ble gate array (FPGA) or other programmable logic de-vice, discrete gate or transistor logic, discrete hardwarecomponents, electrical components, optical compo-nents, mechanical components, or any combinationthereof designed to perform the functions describedherein, and may execute codes or instructions that residewithin the IC, outside of the IC, or both. A general purposeprocessor may be a microprocessor, but in the alterna-tive, the processor may be any conventional processor,controller, microcontroller, or state machine. A processormay also be implemented as a combination of computingdevices, e.g., a combination of a DSP and a microproc-essor, a plurality of microprocessors, one or more micro-processors in conjunction with a DSP core, or any other

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such configuration.[0109] It is understood that any specific order or hier-archy of steps in any disclosed process is an example ofa sample approach. Based upon design preferences, itis understood that the specific order or hierarchy of stepsin the processes may be rearranged while remainingwithin the scope of the present disclosure. The accom-panying method claims present elements of the varioussteps in a sample order, and are not meant to be limitedto the specific order or hierarchy presented.[0110] In one or more exemplary embodiments, thefunctions described may be implemented in hardware,software, firmware, or any combination thereof. If imple-mented in software, the functions may be stored on ortransmitted over as one or more instructions or code ona computer-readable medium. Computer-readable me-dia includes both computer storage media and commu-nication media including any medium that facilitatestransfer of a computer program from one place to anoth-er. A storage media may be any available media that canbe accessed by a computer. By way of example, and notlimitation, such computer-readable media can compriseRAM, ROM, EEPROM, CD-ROM or other optical diskstorage, magnetic disk storage or other magnetic storagedevices, or any other medium that can be used to carryor store desired program code in the form of instructionsor data structures and that can be accessed by a com-puter. Also, any connection is properly termed a compu-ter-readable medium. For example, if the software istransmitted from a website, server, or other remotesource using a coaxial cable, fiber optic cable, twistedpair, digital subscriber line (DSL), or wireless technolo-gies such as infrared, radio, and microwave, then thecoaxial cable, fiber optic cable, twisted pair, DSL, or wire-less technologies such as infrared, radio, and microwaveare included in the definition of medium. Disk and disc,as used herein, includes compact disc (CD), laser disc,optical disc, digital versatile disc (DVD), floppy disk andblu-ray disc where disks usually reproduce data magnet-ically, while discs reproduce data optically with lasers.Combinations of the above should also be included withinthe scope of computer-readable media. It should be ap-preciated that a computer-readable medium may be im-plemented in any suitable computer-program product.[0111] The previous description of the disclosed as-pects is provided to enable any person skilled in the artto make or use the present disclosure. Various modifica-tions to these aspects will be readily apparent to thoseskilled in the art, and the generic principles defined hereinmay be applied to other aspects without departing fromthe scope of the disclosure. Thus, the present disclosureis not intended to be limited to the aspects shown hereinbut is to be accorded the widest scope consistent withthe principles and novel features disclosed herein.

Claims

1. A method of communication, comprising:

receiving (302) a message at a network nodethat indicates that an access terminal is beinghanded-over to a target access point, whereinthe message is received from the target accesspoint;comparing (304) a closed subscriber groupidentifier of the target access point with closedsubscriber group subscription information forthe access terminal; anddetermining (306) whether to allow the accessterminal to be handed-over to the target accesspoint based on the comparison.

2. The method of claim 1, wherein the message com-prises a path switch request message.

3. The method of claim 1, further comprising sending(308) an indication of the determination to the targetaccess point.

4. The method of claim 1, wherein the message com-prises a handover request acknowledge message.

5. The method of claim 4, wherein the message is re-ceived in response to a handover request messagesent to the target access point.

6. The method of claim 1, wherein the determination ismade by a mobility manager for the handover.

7. The method of claim 1, wherein the target accesspoint comprises a femto access point.

8. An apparatus (1400) for communication, comprising:

means (1402) for receiving a message at a net-work node that indicates that an access terminalis being handed-over to a target access point,wherein the message is received from the targetaccess point;means (1404) for comparing a closed subscribergroup identifier of the target access point withclosed subscriber group subscription informa-tion for the access terminal; andmeans (1406) for determining whether to allowthe access terminal to be handed-over to thetarget access point based on the comparison.

9. The apparatus (1400) of claim 8, wherein the mes-sage comprises a path switch request message.

10. The apparatus (1400) of claim 8, further comprisingmeans for sending an indication of the determinationto the target access point.

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11. A computer program comprising instructions whichcause a computer to perform a method according toany of claims 1 to 7, when executed.

Patentansprüche

1. Verfahren zur Kommunikation, aufweisend:

Empfangen (302) einer Nachricht bei einemNetzwerkknoten, welche anzeigt, dass ein Zu-gangsendgerät an einen Zielzugangspunktübergeben wird, wobei die Nachricht von demZielzugangspunkt empfangen wird;Vergleichen (304) einer Kennung für eine ge-schlossene Teilnehmergruppe des Zielzu-gangspunkts mit Information für eine geschlos-sen Teilnehmergruppe für das Zugangsendge-rät; undErmitteln (306), ob es dem Zugangsendgerätgestattet ist, an einen Zielzugangspunkt über-geben zu werden basierend auf dem Vergleich.

2. Verfahren nach Anspruch 1, wobei die Nachricht ei-ne Pfadwechselanforderungsnachricht aufweist.

3. Verfahren nach Anspruch 1, weiter aufweisend dasSenden (308) einer Anzeige des Ermittelns an denZielzugangspunkt.

4. Verfahren nach Anspruch 1, wobei die Nachricht ei-ne Übergabeanfragebestätigungsnachricht auf-weist.

5. Verfahren nach Anspruch 4, wobei die Nachricht inAntwort auf eine Übergabeanforderungsnachrichtempfangen wird, welche an den Zielzugangspunktgesendet wird.

6. Verfahren nach Anspruch 1, wobei das Ermitteln voneinem Mobility Manager für die Übergabe gemachtwird.

7. Verfahren nach Anspruch 1, wobei der Zielzugangs-punkt einen Femtozugangspunkt aufweist.

8. Vorrichtung (1400) zur Kommunikation, aufweisend:

Mittel (1402) zum Empfangen einer Nachrichtbei einem Netzwerkknoten, welche anzeigt,dass ein Zugangsendgerät an einen Zielzu-gangspunkt übergeben wird, wobei die Nach-richt von dem Zielzugangspunkt empfangenwird;Mittel (1404) zum Vergleichen einer Kennungfür eine geschlossene Teilnehmergruppe desZielzugangspunkts mit Information für eine ge-schlossene Teilnehmergruppe für das Zu-

gangsendgerät; undMittel (1406) zum Ermitteln, ob es dem Zu-gangsendgerät gestattet ist, an einen Zielzu-gangspunkt übergeben zu werden basierendauf dem Vergleich.

9. Vorrichtung (1400) nach Anspruch 8, wobei dieNachricht eine Pfadwechselanforderungsnachrichtaufweist.

10. Vorrichtung (1400) nach Anspruch 8, weiter aufwei-send Mittel zum Senden einer Anzeige des Ermit-telns an den Zielzugangspunkt.

11. Computerprogramm aufweisend Anweisungen, wel-che einen Computer dazu veranlassen, ein Verfah-ren nach einem der Ansprüche 1 bis 7 durchzufüh-ren, wenn diese ausgeführt werden.

Revendications

1. Procédé de communication, comprenant :

la réception (302) d’un message dans un noeudde réseau qui indique qu’un terminal d’accès esten cours de transfert à un point d’accès cible,dans lequel le message est reçu du point d’ac-cès cible ;la comparaison (304) d’un identifiant de grouped’abonnés fermé du point d’accès cible à desinformations d’abonnement de groupe d’abon-nés fermé pour le terminal d’accès ; etla détermination (306) s’il faut autoriser que leterminal d’accès soit transféré au point d’accèscible sur la base de la comparaison.

2. Procédé selon la revendication 1, dans lequel lemessage comprend un message de demande decommutation de trajet.

3. Procédé selon la revendication 1, comprenant enoutre l’envoi (308) d’une indication de la détermina-tion au point d’accès cible.

4. Procédé selon la revendication 1, dans lequel lemessage comprend un message d’acquittement dedemande de transfert.

5. Procédé selon la revendication 4, dans lequel lemessage est reçu en réponse à un message de de-mande de transfert envoyé au point d’accès cible.

6. Procédé selon la revendication 1, dans lequel la dé-termination est faite par un gestionnaire de la mobi-lité pour le transfert.

7. Procédé selon la revendication 1, dans lequel le

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point d’accès cible comprend un point d’accès femto.

8. Appareil (1400) de communication, comprenant :

un moyen (1402) pour recevoir un messagedans un noeud de réseau qui indique qu’un ter-minal d’accès est en cours de transfert à un pointd’accès cible, dans lequel le message est reçudu point d’accès cible ;un moyen (1404) pour comparer un identifiantde groupe d’abonnés fermé du point d’accès ci-ble à des informations d’abonnement de grouped’abonnés fermé pour le terminal d’accès ; etun moyen (1406) pour déterminer s’il faut auto-riser que le terminal d’accès soit transféré aupoint d’accès cible sur la base de la comparai-son.

9. Appareil (1400) selon la revendication 8, dans lequelle message comprend un message de demande decommutation de trajet.

10. Appareil (1400) selon la revendication 8, compre-nant en outre un moyen pour envoyer une indicationde la détermination au point d’accès cible.

11. Programme d’ordinateur comprenant des instruc-tions qui amènent un ordinateur à réaliser un procé-dé selon l’une quelconque des revendications pré-cédentes 1 à 7, lorsqu’elles sont exécutées.

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