I||||||||||||||||||||||||||||||||||l1||||| ||||||l||||||||||||||||||||||||||
`
`US0089?"7258B2
`
`(12) United States Patent
`Chou
`
`(10) Patent No.:
`
`(45; Date of Patent:
`
`US 8,977,258 B2
`Mar. 10, 2015
`
`(56)
`
`References Cited
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`370-"338
`455.-435.1
`3'?0»"39S.4
`370-"208
`370-"316
`3'10.-282
`455-"436
`3703310
`
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`375,340
`371}.-453
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`6.404.754 131*
`7.437.157 131 1*
`2003.='007683'r‘ Al *
`.~’\l ‘I
`200-’-00233838 .311"
`200550068915 Al *
`200510201304 Al"‘
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`3,.-‘gum Jain
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`OTHER PUBLICATIONS
`“IF.F.E Standard 802.16aT”—lEEE Standard for Local and Metro-
`
`politan Area l\'etworks. P311 10: Air Interface for Fixed Broadband
`Wireless Access Systems—Amendment 2: Medium Access Control
`Modifications and Additional Physical Layer Specifications for 2 -l 1
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`PM-C‘
`ABS.l.RAC.l.
`(57)
`l£mbodi1'11e11ts of System and Method for Comittuiticatirtg
`within Broadband Wireless Networks are generally described
`herein. Otlter embodiments may be described and claimed.
`
`(54)
`
`SYSTEM AN D METHOD FOR
`(IOMMUNICATING WITH FIXED A:\D
`MOBILE SUBSCRIBER STATIONS IN
`BROADBAND WIRELESS A( ICESS
`.
`,
`.
`,
`*l’51W"RK5
`
`(75)
`
`(73)
`
`Illventgr:
`_
`Asslgneei
`
`Joey! (Thou. Scottsdale‘
`_
`ll1t°'C0I‘P01‘ati0IJ.-Santa Clara-CA
`(US)
`
`(*1
`
`.
`Nultce:
`
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`_.
`._
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`.
`§|lllJ_]{:C1-10 any d15cl.111n<.r.- 1111. 11.r111 oflhm
`patent 15 extended or £lCl_]lJSl.E(Ll under 35
`U.S.(.‘. 154-(b) by 1596 days.
`
`(21)
`
`.‘\pp1.No.:
`
`llf222,6'I-'5
`
`(22)
`
`Ffled:
`
`Scp_ 9‘ 2005
`
`(65)
`
`(51)
`
`(52)
`
`(53)
`
`Priflr Publication Data
`Us 2007;0.07(,(,39 A]
`_¢_-‘pl-1 5‘ 2007
`
`Int CL
`H04”, 4,90
`H041. 12/24
`H()4W 84/04'
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`U_§_ (j]_
`crpc.‘
`
`(200901 )
`(2006.01)
`(2009.01)
`(2001101)
`(200901)
`
`H041’. 41/0213 (201301 1; H041, 4L"0226
`(2013.01): H041-‘V 84/04 (2013.01); Hf)-’.\'W 88/10
`(2013.01): H0-¢W92/02 (2013.01)
`USPC
`4551'-435.1: 45Sr’435.2; 45515’-135.3
`Field of Classification Search
`USPC
`
`4551‘435.l—435.3
`
`See application file for complete Search history.
`
`21 Claims, 7 Drawing Sheets
`
`APPLE 1010
`
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`
`1
`
`

`
`US 8,977,258 B2
`Page 2
`
`(56)
`
`References Cited
`
`OTHER PUBLICATIONS
`“IEEE Standard 802.l6e'"“——IEEE Standard for Local and Metro-
`politan Area Networks. Part 16: Air Interface for Fixed and Mobile
`Broadband Wireless Access Systems. Amendment 2: Physical and
`Medium Access Control Layers for Combined Fixed and Mobile
`Operation in Licensed Bands and Corrigendum 1". HSEE Std. 802.
`I6eT”—2Ut95 rmd IEEE Sm’. 802.367-“—2004fCoi‘} —2005 (.4meJ1'd—
`mm: and Corrigetrdmrr to IEEE 802..’6—20t?-i). The Institute of
`Electrical and Electronics Engineers. Inc.. New York. NY. (2006),
`864 pgs.
`
`“IEEE Standard 3t]2.l61T'“—IF.EE Standard for Local and Metro-
`politan Area Networks. Part 16: Air Interface for Fixed Broadband
`Wireless Access Systems—Amend.ment
`I: Management Informa-
`tion Base”. IEEE Std. 8U2.Id,I'7""
`-2005, IEEE, New York. NY.
`(2005), 257 pgs.
`Chou. J.. at al.. "MAC and PHY MIB fur WirelessMAN and
`Wirelessliuman BS and SS”, (Jul. 9._ 2004). 1-120.
`Liang. (7.. "Wireless awareness for wireless intelligent network“.
`Communications. 2003. APCC 2003, 2. The 9th Asia-Pacific
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`
`* cited by examiner
`
`2
`
`

`
`U.S. Patent
`
`Mar. 10, 2015
`
`Sheet 1 of 7
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`US 8,977,258 B2
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`U.S. Patent
`
`Mar. 10, 2015
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`U.S. Patent
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`Mar. 10, 2015
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`
`Mar. 10, 2015
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`Mar. 10, 2015
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`US 8,977,258 B2
`
`1
`SYSTEM AND METHOD FOR
`(IOMMUNl(.‘ATING WITI-I FIXED AND
`MOBILE SUBSCRIBER S'l'A'l'IONS IN
`BROADBAND WIRELESS ACCESS
`NETWORKS
`
`"l'l'.i(TI'lNl(IAl. I-‘Il.i.[..l)
`
`Embodiments of the present invention pertain to wireless
`networks and wireless communications. Some embodiments
`pertain to broadband wireless access (BWA) networks.
`
`1U
`
`BAC KGROUNI )
`
`In wireless communication networks. including broadband
`wireless access (BWA) networks. a base station may desire to
`communicate with many different types of subscriber sta-
`tions. including fixed subscriber stations and mobile sub-
`scriber stations. Subscriber stations operating in accordance
`with different network protocols and standards may wish to
`concurrently communicate with a base station. Examples of
`different network protocols and standards include the Insti-
`tute of Electrical and I-Electronic Engineers (IEEE) 802. l6(e)
`proposed specification tor both mobile and fixed subscriber
`stations and the IIEI-EE 802.16-2004 standard for fixed sub-
`scriber stations. These standards are referenced below.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`FIG. 1 illustrates a broadband wireless access [l3WA) net-
`work in accordance with some embodiments of the present
`invention:
`
`FIG. 2 illustrates an example of a base station interface
`table in accordance with some ernbodiments of the present
`invention;
`FIG. 3 is a tlow chart of a downlink synchronization pro-
`cedure in accordance with some embodinients of the present
`invention;
`FIG. 4 is a How chart of a base station network entry
`procedure in accordance with some embodiments of the
`present invention;
`FIG. 5 illustrates an example ofa management infomiation
`base (MIB) structure in accordance with some embodiments
`of the present invention:
`FIG. 6 illustrates an example ofa base station capabilities
`subtree in accordance with some embodiments of the present
`invention: and
`
`FIG. 7 illustrates an example of a base station physical
`(PHY) layer subtree in accordance with some embodiments
`of the present invention.
`
`DETAI LEI) l)I-ESCRIPTION
`
`The following description and the drawings illustrate spe-
`cific embodiments of the invention sufficiently to enable
`those skilled in the art to practice them. Other embodiments
`may incorporate structural, logical. electrical. process. and
`other changes. Examples merely typify possible variations.
`Individual components and functions are optional unless
`explicitly required. and the sequence of operations may vary.
`Portions and features of some embodiments may be included
`in or substituted for those of others. Embodiments of the
`
`invention set forth in the claims encompass all available
`equivalents of those claims. Embodiments of the invention
`may be referred to. individually or collectively. herein by the
`term “invention" merely for convenience auid without intend-
`
`3o
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`2
`
`ing to limit the scope of this application to any single inven-
`tion or inventive concept ifmore than one is in fact disclosed.
`FIG. 1 illustrates a broadband wireless access (BWA) net-
`work in accordance with some ernbodiments of the present
`invention. Broadband wireless network 100 includes base
`station (BS) 102 which may communicate with one or more
`fixed subscriber stations (SS) 104 and one or more 111obilc
`subscriber stations (MS) 106. Base station 102 may be
`coupled through network I08 to network management sys-
`tem (NMS) 112. servers 116 and database 114. Network 108
`may be an internet-protocol (IP) based network, such as the
`internet_. although the scope of the invention is not limited in
`this respect.
`Network I08 111ay be based on the llzilili 802. l6-2004 stan-
`dard andfor I£€lI-Liz‘ 802. l6(e) proposed specification for wire-
`less metropolitan area networks [WMAN) referenced below.
`although the scope of the invention is not limited in this
`respect. Base station 102 includes management ittforntation
`base (M113) 120 that may be managed directly by network
`management system 112. Subscriber stations 104 may also
`include subscriber stations management information bases
`122 that may be managed directly by network management
`system 112. or indirectly by base station 102 which acts as a
`front-end proxy. In some embodiments. the front-end proxy
`may unwrap packets to determine to which subscriber station
`104 a packet should be forwarded based on the packet con-
`text. The packets may include nianagcntcnt network protocol
`packets. such as simple network management protocol
`(SNMP) packets. although the scope of the invention is not
`limited in this respect. Mobile subscriber stations 106 may be
`notebook client devices. for example. that may not include an
`MIB. Mobile subscriber stations 106 may be managed indi-
`rectly via base station 102 which may act as a back—end proxy.
`In these embodiments, the back-end proxy may convert the
`SNMP packets to a management protocol that mobile sub-
`scriber stations are running.
`In accordance with some embodiments of the present
`invention. the front-end proxy may be viewed as per-packet
`multiplexing as the proxy operation occurs before the SNMP
`packet has been completely parsed and before any of the
`packet‘ s VarBinds are examined. A packet may include one or
`more V"arBinds that reference addition infomiation. such as
`indications of causes of failures. A description may be
`decoded from the VarI3ind. For example,
`if an SNNIPV3
`request packet is to be rejected by an SNMP agent, the agent
`may send a report packet that contains one or tnore VarBinds
`showing the cause offailures. An SNMI’ manager application
`may decode the description of the failures from the one or
`more VarBinds. Each SNMP message may be forwarded in its
`entirety to a new destination determined by the context of the
`request. Context is an attribute of an SNMP request that was
`created after the community string. In SNMPV3 (which does
`not use community strings}. the context is specified sepa-
`rately from the authentication secret.
`In SNMPVI and
`SNMPv2c, the community string serves a dual role as the
`authentication secret and as the context. Context may com-
`prise a collection of management information accessible by
`an SNMP entity. An item of management information may
`exist in more than one context. An SNMP entity potentially
`has access to many contexts.
`In accordance with some embodiments of the present
`invention. the back—end proxy. on the other hand. may be
`viewed as per—VarBi11d multiplexing as the proxy operation
`may occur after the SNMP packet has been completely parsed
`and while the \r"arBinds are being processed individually. This
`
`10
`
`10
`
`

`
`3
`
`4
`
`US 8,977,258 B2
`
`fronting may occur at the point where the SNMP agent would
`nonnally exchange data directly with the application’s data
`registers.
`In some embodiments, fixed subscriber stations 104 may
`be managed nodes. A managed node refers to devices that are
`managed by a management station of network management
`system 112. For example, fixed subscriber stations 104 and
`base station 102 may be managed nodes. The management
`agent may be an SN MP agent. In some embodiments. a man-
`aged device may be a network node that includes an SN MP
`agent and resides on a managed network. Managed devices
`may collect and store management
`information and may
`make the collected information available to network manage-
`ment system 112 using SNMP, for example. Managed devices
`may also include network elements and can be routers and
`access servers, switches and bridges. hubs, computer hosts, or
`printers. for example. In some embodiments, an agent may be
`a network-management mzuiagement software module that
`may resides in a managed device. In some embodiments. an
`agent has local knowledge of management information and
`translates that
`information into a form compatible with
`SNMP. In some embodiments. network management system
`112 may execute applications that monitor and control man-
`aged devices. Network management system 112 may provide
`the bulk of the processing and memory resources required for
`network managenient. although the scope of the invention is
`not limited in this respect.
`In some embodiments, the management information base
`defined by some embodiments of present invention 111ay
`allow the migration ofconventionai management" infonnation
`bases to support both mobile and lixed subscriber stations.
`such as fixed subscriber station based on the IEEE 802.16-
`2004 standard and mobile and lixed subscriber stations based
`
`on the llil-El-3 802.l6(e) proposed specification. although the
`scope of the invention is not limited in this respect. In some
`embodiments. a standards based MIB and method to manage
`IEEE 802. l6(e) based BWA networks is provided which may
`be very robust to support both llillli 802.16-2004 fixed and
`IEEE 802.l6(e) mobile networks simultaneously. In some
`embodiments. the MIR and method may be flexible enough to
`support mobile subscriber stations that may use non-SNMP
`based management protocol. In accordance with embodi-
`ments ofthe present invention, through messages exchanged
`during subscriber station network entry and capability nego-
`tiation. base station 102 determines the IVLAC version and
`whether fixed and mobile subscriber stations support mobil-
`ity.
`In accordance with some embodiments of the present
`invention. base station 102 may be able to manage both fixed
`subscriber stations 104 and mobile subscriber stations 106
`
`simultaneously when base station 102 has multiple sectors to
`support the llilili 802.16-2004 standard and the ll.§l:il£ 802.16
`(e) proposed specification. separately.
`In accordance with some embodiments of the present
`invention, base station 102 may be able to manage both fixed
`subscriber stations 104 and mobile subscriber stations 106
`
`siniultaneously when base station 102 has multiple sectors to
`support. IEEE 80216-2004 and IEEE 802.16(e) standards.
`separately.
`In some embodiments, base station 102. fixed subscriber
`stations 104 and mobile subscriber stations 106 may comn1u-
`nicate either orthogonal
`frequency division multiplexed
`(OFDM) communication signals or orthogonal frequency
`division multiple access [OFDMA) communication signals
`over a multicarrier communication channel. The multicarrier
`communication channel may be within a predetermined fre-
`quency spectrum and may comprise a plurality of orthogonal
`
`subcarriers. In some embodiments. the orthogonal subcarri-
`ers may be closely spaced subcarriers. To help achieve
`ortliogonality between the closely spaced subcarriers. each
`subcarrier may have a null at substantially a center frequency
`of the other subcarriers and!or each subcarrier may have an
`integer nurnberofcycles within a symbol period, although the
`scope of the invention is not limited in this respect.
`In some embodiments, base station 102 may be a Wireless
`Fidelity (Wil-‘i). Worldwide Interoperability for Microwave
`Access (Wih/lax], or broadbzmd communication station.
`although the scope of the invention is not limited in this
`respect. In some embodiments. mobile subscriber stations
`106 may be portable wireless communication devices, such
`as personal digital assistants (I’DAs), a laptop or portable
`computers with wireless communication capability. web tab-
`lets. wireless telephones wireless headsets, pagers. instant
`messaging devices. or other mobile devices that may receive
`andtor transmit information wirelessly.
`In some embodiments, the frequency spectruzns for the
`rnulticarrier comrnunication signals communicated by base
`station 102. subscriber stations 104 and mobile subscriber
`stations 106 may comprise either a 5 GHZ frequency spec-
`trum or a 2.4 (31-12 frequency spectrum. In these embodi-
`ments, the 5 GI-lz frequency spectrum may include frequen-
`cies ranging from approximately 4.9 to 5.9 GHZ. and the 2.4
`GI-Iz spectrum may include frequencies ranging from
`approximately 2.3 to 2.5 GI-Ix. although the scope of the
`invention is not limited in this respect, as other frequency
`spectrums are also equally suitable. In some broadband and
`Wilvlax embodiments, the frequency spectrum for communi-
`cations may comprise frequency channels between 2 and 11
`GHZ. although the scope ofthe invention is not limited in this
`respect.
`In some embodiments. base stat ion 102. subscriber stations
`104 and mobile subscriber stations 106 may communicate in
`accordance with specific communication standards. such as
`the IEEE standards and proposed specifications including the
`[El-EE 802.16 standard for wireless metropolitan area net-
`works [WiV1ANs). although the scope of the invention is not
`limited in this respect. For more information with respect to
`Ilil-Eli 802.16 standards. please refer to “lI*}l;ili Standards for
`Information Technology—Telecommunications and Infor-
`mation Exchange between Systems—Local and Metropoli-
`tan Area Network—Specific Requirements—l’art 16: ISO!
`[EC 8802-16: 1999” and related amendineiitslversioiis.
`
`Base station 102 may include one or more antennas 119,
`each of which may be associated with a different sector.
`Subscriber stations 104 may also include one or more anten-
`nas H8. Mobile subscriber stations 106 may also include one
`or more antennas not separately illustrated. Antennas 118 and
`119. including the antennas ofmobile subscriber stations 106.
`may comprise one or more directional or omnidirectional
`antennas. including, for example. dipole antennas, monopole
`antennas. patch antennas. loop antennas. microstrip antennas
`or other types of antennas suitable for transmission of radio-
`frequency (RF) signals. In some embodiments. instead oftwo
`or more antennas, a single antenna with multiple apertures
`may be used.
`Although the elements of base station 102. subscriber sta-
`tions 1 04 and mobile subscriber stations 1 06 are illustrated as
`
`several separate functional elements. one or more ofthe finic-
`tional elements may be combined and may be implemented
`by combinations of software-configured elements. such as
`processing elements including digital signal processors
`(DSl’s}_. andtor other hardware elements. For example. some
`elements may comprise one or more microprocessors. l)SPs.
`application specific integrated circuits (ASl(_‘s), and combi-
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`nations of various hardware and logic circuitry for perform-
`ing at least the functions described herein. In some embodi-
`ments. the functional elements base station 102. subscriber
`stations 104 and mobile subscriber stations 106 may refer to
`one or more processes operating on one or more processing
`eletnents.
`FIG. 2 illustrates an example of a base station interface
`table in accordance with some embodiments of the present
`invention. Base station interface (it) table 200 may be ttsed to
`cliaracterize a multi-sector base station. such as base station
`102 that supports OFDM and OFDMA communications with
`various fast-I"ourier'l'ransforrn (FFT) sizes. In this example.
`table 200 may be used to charact-eri7,e a five sector base station
`for FFT sizes of204-8, 1024, 512. and 128, although the scope
`of the present invention is not limited in this respect. The
`sectors may correspond to different antenna sectors of a base
`station. In sortie embodiments. the base station may employ
`orthogonal communications at least within each adjacent sec-
`ter. In some embodiments. when base station 102 communi-
`cates with the fixed and mobile subscriber stations within a
`plurality of anterma sectors. base station 102 may simulta-
`neously communicates with at least some of the admitted
`mobile subscriber stations and at least some of the fixed
`
`subscriber station ttsing differing fast Fourier transform
`(FFT) sizes identified iii the management infonnation base. In
`these embodiments, at least some of the antenna sectors using
`the different I"i’T sizes. In some embodiments. prior to trans-
`mitting the network admission requests, the fixed and mobile
`subscriber stations may synchronize to downlink channels
`transmitted by base station 102 by attempting to synchronize
`with a frame preamble for different channels and different
`FFT sizes to determine a correct channel and F FT size being
`used by base station 102. and wherein after the correct chan-
`nel and FITT size are detcrtnined. the fixed and mobile sub-
`scriber stations attempt to process a frame control header for
`different cyclic prefix sizes to determine a correct cyclic
`prefix size.
`As illustrated in Table 200. a base station may communi-
`cate with subscriber stations and mobile subscriber stations
`
`based on the following physical (PHY) layer configurations:
`a SS based on II-it-?.I_i 802.16-2004 (i.e.. OFDM 256 or
`OFDMA 2048}; a SS based on IEEE 802.16(e)(i.e.. OFDMA
`with an FFT size of 1024. 512, and 128) and a MS based on
`IEEE 802.16(e) (i.e.. OFDMA with an FFT size of I 024. 512.
`and I28). The use of table 200 within a base station is dis-
`cussed in more detail below.
`
`FIG. 3 is a How chart of a down] ink synchronization pro-
`cedure in accordance with some embodiments of the present
`invention. Downlink synchronization procedure 300 may be
`performed by either mobile subscriber stations. such as
`mobile subscriber stations 106 (FIG. 1). or fixed subscriber
`stations. such as fixed subscriber stations 104 (FIG. 1), to
`attempt to synchronize with a base station. such as base
`station 102 (FIG. I). and receive a downlink (l)I_.) channel. As
`part ofdownlink synchronization procedure 300, a subscriber
`station attempts to determine the frequency channel. the FFT
`size and the cyclic prefix (GP) size for subsequent admission
`to a broadband wireless access network, such as network 100
`(FIG. 1) and communication with the base station. such as
`base station 102 (FIG. 1).
`As shown in operations 302 through 316. the subscriber
`station attempts to properly receive a preamble of the down-
`link signals from the base station for different channels and
`different FFT sizes. In operation 302, the subscriber station
`determines and sets the channel. In operation 304, the sub-
`scriber station sets the I-‘I-”l‘ size. and in operation 306. the
`subscriber station sets the cyclic prefix (CP) size. In operation
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`308, the subscriber station attempts to synchronized with and
`receive the preamble on the downlink ([)L) using the channel.
`FFT size and CI’ size from operations 302 through 306. Once
`the subscriber station is able to synchronize with the pre-
`amble in operation 308, the channel and FI'"I" size is correct.
`The subscriber station can then determine the proper size of
`the cyclic prefix i11 operations 3 18 through and 322. When the
`cyclic prefix is correct. the frame control header (FCH) will
`be received properly in operation 318. Ifthe subscriber station
`exhausts all possible F FT sizes through the pcrfonnance of
`operations 310 and 31 2 without being able to properly receive
`the downlink preamble, and when the number of channels is
`not exhausted, as determined in operation 314, a new chamtel
`may be selected i11 operation 316 allowing the syncl1roniza-
`tion to be performed on the newly selected channel. if the
`station exhausts all channels and FFT sizes through the per-
`fortnance ofopcrations 310. 312 and 314, or if the subscriber
`station exhausts all possible cyclic prefixes through the per-
`formance of operations 320 and 322 without being able to
`receive the FC H. synchronization may fail in operation 324
`and the mobile or fixed subscriber station may not be able to
`communicate with the base station.
`When the FCI-I is properly received in operation 318, the
`subscriber station may set the FFT size object in operation
`326 and may transmit a network entry request message. such
`as a tattgittg request (RNG_RI'.*lQ) to the base station in opera-
`tion 328.
`I11 some embodiments, the downlink PHY data units traits-
`mitted by the base station may begin with a long preamble,
`which is used for PHY synchronization. The preaunble may
`be followed by a FCI-I burst that contains a downlink front
`prefix which specifies the burst profile and length of one or
`severai downlink bursts immediately following the I’(.'iI.
`When the FCH is received and decoded correctly, the CP size
`is set correctly.
`FIG. 4 is a How chart of a base station network entry
`procedure in accordance with some embodiments of the
`present invention. Network entry procedure 400 may be per-
`formed by a base station, such as base station 102 (FIG. I). for
`admitting a fixed or mobile subscriber station to the network.
`Procedure 400, among other things. detennjnes the opera-
`tional ntode ofthe fixed or mobile subscriber station request-
`ing network entry.
`In operation 402. a ranging request
`(l{NG_RI-_iQ) may be received at the base station. The ranging
`request may have been transmitted by the subscriber or
`mobile subscriber station in operation 328 (FIG. 3). As part of
`network entry procedure 400, a base station may generate and
`or update its management information base 120 (FIG. 1) for
`the newly admitted fixed or mobile subscriber station. In
`operation 404, the base station detennines whether the traits-
`mitting subscriber station is a station operating in accordance
`with the III-LEIEZ 802.16-2004 standard. If so, operations 406
`through 410 are perlbrmed.
`If in operation 404. the base station determines that the
`transmitting subscriber station is a station operating in accor-
`dance with the IEEE 802.16(e) proposed specificatiort, a reg-
`istration request (REG_REQ) may be received in operation
`412. Operation 414 determines whether or not the transmit-
`ting subscriber station supports a mobility feature. If the
`mobility feature is supported. the transmitting station is a
`mobile subscriber station. such as one of tnobile subscriber
`stations 106 (FIG. 1). and operations 416-420 are perfonned.
`If the mobility feature is not supported, the transrnjtting sta-
`tion is a fixed subscriber station. such as one of fixed sub-
`scriber stations 104 (FIG. I), and operations 422-426 are
`performed.
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`In some embodiments. operation 406 may (described in
`abstract syntax notation [ASN}] set MAC‘ version object
`wrnanIfBsMac\/ersion=ieee802 Dotl(i0f2004_. and may set
`mobility object—handoverSupport. sleepModeSupport_. and
`idleModeSupport bits in wmanlfI3sMsOfdmaRcqCapMo-
`bilityFeat1u'e to “0”. Operation 408 may include receiving the
`mobility object and operation 410 may include identifying
`the station as an 802.16-2004 mobile station.
`In some
`embodiments. operation 416 may set MAC version object
`wmanIlBsMacVersion to ieee802 Dotlée. and may set
`mobility object—handoverSupport_. sleepModeSnpport_. and
`idleModeSupport bits in wmanlIlisMs0l‘dmaRcqCapMo-
`bi1ityl'-‘eature to “l". Operation 418 may include receiving the
`mobility object and operation 420 may include identifying
`the station as an 80Q.l6e mobile station. In some embodi-
`ments, operation 422 may set MAC version object—wmanl-
`l'BsMacV"ersion to ieee802 Dotlée. and may set mobility
`object—handoverSupport_. sleepModeSupport_. and idleM-
`odeSuppot1
`bits
`in wmanlfl3sMsOfdmaReqCapMobili-
`tyl--‘eature to
`Operation 424 may include receiving the
`mobility object and operation 426 may include identifying
`the station as an 802.16e subscriber station. These table
`entries are described in more detail below.
`
`FIG. 5 illustrates an example ofa management information
`base (MIBJ structure in accordance with some embodiments
`of the present invention. MIB structure 500 (wmanl lMib) is a
`high level MII3 which may be suitable for use with base
`station 102 (FIG. 1) including base stations operating in
`accordance with IEEE 802.16 standards, although the scope
`of the invention is not limited in this respect. In these example
`embodiments. M113 structure 500 is organized based on the
`reference model as defined in IEEE 802,16-2004 standard.
`
`MIB structure 500 includes ofthree groups: wrnanI[BsOb-
`jects 502. which includes managed objects to be iniplemented
`in the SNMP agent in the base station, wmanllSsObjects 504
`which includes managed objects to be implemented in the
`SNMP agent in the subscriber stations. and wmanIfC"orn-
`mon()bjects 506 which includes common managed objects to
`be implemented in the SNMP agent in the base station and
`subscriber stations. In some embodiments. MIB structure 500
`may describe enhancements for IlEF.E. 802.16f MIBS to sup-
`port mobility features. The wn1anIlBsCp_. for example.
`is
`described in FIG. 6 below.
`
`FIG. 6 illustrates an example ofa base station capabilities
`subtree in accordance with some embodiments of the present
`invention. Base station capabilities subtree 600 includes two
`new tables wmanllBsNeigl1borAdvertiseTable and wmanI-
`ll}sPowerSavingClassTable. WrnanllMacVersion includes
`an entry to indicate the 302.1 6(e) version of MAC software
`that the registered subscriber station is running. These tables
`and their entries are described in 111ore detail below.
`FIG. 7 illustrates an example of a base station physical
`(PHY) layer subtree in accordance with some embodiments
`of the present invention. Base station physical layer subtree
`700 (wmanllBsPl1y subtree) includes four new tables identi-
`fied as wrnanIfBsSsOldmaReqCapabilitiesTable. wmanIfB-
`sSsOfdmaRspCapabilitiesTable, wmanIlBsOfdmaCapabili-
`tiesTable.
`and wman]fBs0fdznaCapabilitiesConfigTable.
`These tables and their entries are described in more detail
`below.
`
`Unless specifically stated otherwise. terms such as pro-
`cessing, computing. calculating. determining. displaying. or
`the like, may refer to an action andfor process ofone or more
`processing or computing systems or similar devices that may
`manipulate and transform data represented as physical (e.g._.
`electronic) quantities within a processing system's registers
`and memory i