available under
`Document made
`Patent Cooperation Treaty (PCT)
`
`the
`
`International application number: PCT/US2010/039372
`
`International filing date:
`
`21 June 2010 (21.06.2010)
`
`Document type:
`
`Certified copy of priority document
`
`Documentdetails:
`
`Country/Office: US
`Number:
`61/218,769
`Filing date:
`19 June 2009 (19.06.2009)
`
`Date ofreceipt at the International Bureau:
`
`30 January 2011 (30.01.2011)
`
`Remark:
`
`Priority document submitted or transmitted to the International Bureau in
`compliance with Rule 17.1(a),(b) or (b-dis)
`
`
`
`World Intellectual Property Organization (WIPO) - Geneva, Switzerland
`Organisation Mondiale de la Propriété Intellectuelle (OMPI) - Genéve, Suisse
`1
`APPLE 1010
`
`1
`
`APPLE 1010
`
`

`

`ANS AEsEDWKSGREESE: PRESENES: SHAG, COMES
`
`UNTPED STATES DEPARTMENT OF COMMERCE
`
`United States Patent and Trademark Office
`
`January 29, 2011
`
`Patent and Trademark Office
`
`THIS IS TO CERTIFY THAT ANNEXED HERETOIS A TRUE COPY FROM
`THE RECORDS OF THE UNITED STATES PATENT AND TRADEMARK
`OFFICE OF THOSE PAPERS OF THE BELOW IDENTIFIED PATENT
`APPLICATION THAT MET THE REQUIREMENTS TO BE GRANTED A
`FILING DATE.
`
`APPLICATION NUMBER: 61/218,769
`FILING DATE: June 19, 2009
`RELATED PCT APPLICATION NUMBER: PCT/US10/39372
`
`THE COUNTRY CODE AND NUMBER OF YOUR PRIORITY
`APPLICATION, TO BE USED FOR FILING ABROAD UNDER THE PARIS
`CONVENTION,IS US61/218,769
`
`Certified by
`
`UnderSecretary of Conmierce
`for letellectual Property
`and Director af the United States
`
`2
`
`

`

`DOCKETNO, 092546P1
`
`CLAIMS
`
`1,
`
`A method, comprising:
`
`associating a plurality of carriers utilized for communication into one or more
`
`timing groupsof carriers;
`
`assigning a candidate carrier in at least one of the one or more timing groups for
`
`timing updates;
`
`receiving a timing offset from the candidate carrier during a timing update; and
`
`updating timing for each carrier in the at least one timing group based on the
`
`timing offset.
`
`Zi
`
`The method of claim 1, wherein assigning the candidate carrier includes
`
`selecting the candidate carrier according to a hash function.
`
`3.
`
`The method of claim 2, wherein the hash function utilizes a variable key
`
`such that the candidate carrier differs for disparate timing updates.
`
`4,
`
`The method of claim 1, wherein assigning the candidate carrier is
`
`performed according to a received assignment from a base station associated with a
`
`subset of the plurality of carriers.
`
`3
`
`The method of claim |, wherein associating the plurality of carriers into
`
`one or more timing groups includes evaluating a timing difference of each of the
`
`plurality of carriers and grouping the plurality of carriers according to a threshold
`difference.
`
`6.
`
`The method of claim 1, wherein associating the plurality of carriers into
`
`one or more timing groups is performed according to a grouping received from a base
`
`station associated with a subset of the plurality of carriers.
`
`3
`
`

`

`DOCKETNO, 092546P1
`
`16
`
`7.
`
`The method of claim 1, further comprising monitoring a downlink timing
`
`for each carrier in the at
`
`least one timing group and modifying the timing offset
`
`according to an average of the offset applied to the monitored downlink timings for each
`
`carrier.
`
`8.
`
`The method of claim 1, wherein carriers in the at least one of the one or
`
`more timing groups are transmitted at a common site.
`
`9,
`
`The method of claim 8, wherein the timing offset is received in a vector
`
`of a plurality of timing offsets for the at least one of the one or more timing groups from
`the commonsite.
`
`10.
`
`A wireless communications apparatus, comprising:
`
`at least one processor configured to:
`
`generate
`
`an
`
`association of
`
`a plurality of carriers utilized for
`
`communication into one or more timing groups according to a timing of each of
`
`the plurality of carriers;
`
`select a candidate carrier in at least one of the one or more timing groups
`
`for timing updates;
`
`obtain a timing offset from the candidate carrier during a timing update;
`
`and
`
`modify timing for each carrier in the at least one timing group based on
`
`the timing offset; and
`
`a memory coupled to the at least one processor.
`
`11.
`
`The wireless communications apparatus of claim 10, wherein the at least
`
`one processorselects the candidate carrier according to a hash function.
`
`12.
`
`The wireless communications apparatus of claim 11, wherein the hash
`
`function utilizes a variable key such that
`
`the candidate carrier differs for disparate
`
`timing updates.
`
`4
`
`

`

`DOCKETNO, 092546P1
`
`17
`
`13.
`
`The wireless communications apparatus of claim 10, wherein theat least
`
`one processor selects the candidate carrier according to an assignment received from a
`
`base station associated with a subset of the plurality ofcarriers.
`
`14.
`
`The wireless communications apparatus of claim 10, wherein the atleast
`
`one processor generates the association of the plurality of carriers into one or more
`
`timing groups by evaluating a timing difference of each of the plurality of carriers and
`
`grouping the plurality of carriers into the timing groups according to a threshold
`difference.
`
`15.
`
`The wireless communications apparatus of claim 10, wherein the at least
`
`one processor generates the association of the plurality of carriers into one or more
`
`timing groups according to a grouping received from a base station associated with a
`
`subset of the plurality of carriers.
`
`16.|The wireless communications apparatus of claim 10, wherein the at least
`
`one processoris further configured to monitor a downlink timing for each carrier in the
`
`at least one timing group and update the timing offset according to an average of the
`
`offset applied to the monitored downlink timings for eachcarrier.
`
`17.
`
`The wireless communications apparatus of claim 10, wherein carriers in
`
`the at least one of the one or more timing groups are transmitted at a commonsite.
`
`18.
`
`The wireless communications apparatus of claim 17, wherein the at least
`
`one processor obtains the timing offset in a vector of a plurality of timing offsets for the
`
`at least one of the one or more timing groups from the commonsite.
`
`5
`
`

`

`DOCKETNO. 092546PI
`
`18
`
`19.
`
`An apparatus, comprising:
`
`means for associating a plurality of carriers utilized for communication into one
`
`or more timing groupsofcarriers;
`
`means for assigning a candidate carrier in at least one of the one or more timing
`
`groups over which to receive timing updates;
`
`means for receiving a timing offset from the candidate carrier during a timing
`
`update; and
`
`means for updating timing for each carrier in the at least one timing group based
`
`onthe timingoffset.
`
`20.
`
`The apparatus of claim 19, wherein the means for assigning the candidate
`
`carrier selects the candidate carrier according to a hash function.
`
`21.
`
`‘The apparatus of claim 20, wherein the hash function utilizes a variable
`
`key such that the candidate carrier differs for disparate timing updates.
`
`22.
`
`‘The apparatus of claim 19, wherein the means for assigning the candidate
`
`carrier assigns the candidate carrier according to a received assignment from a base
`
`station associated with a subsetof the plurality of carriers.
`
`23.
`
`The apparatus of claim 19, wherein the means for associating the
`
`plurality of carriers into one or more timing groups analyzes a timing difference of each
`
`of the plurality of carriers and groups the plurality of carriers according to a threshold
`difference.
`
`24.
`
`The apparatus of claim 19, wherein the means for associating the
`
`plurality of carriers into one or more timing groups associates according to a grouping
`
`received from a base station associated with a subset of the plurality of carriers.
`
`6
`
`

`

`DOCKETNO, 092546P1
`
`19
`
`25.
`
`The apparatus of claim 19, further comprising:
`
`means for monitoring a downlink timing for each carrier in the at
`
`least one
`
`timing group; and
`
`means for modifying the timing offset according to an average of the offset
`
`applied to the monitored downlink timings for each carrier.
`
`26.
`
`The apparatus of claim 19, whereincarriers in the at least one of the one
`
`or more timing groupsare transmitted at a commonsite.
`
`27.
`
`The apparatus of claim 26, wherein the timing offset is received in a
`
`vector of a plurality of timing offsets for the at least one of the one or more timing
`
`groups from the common site.
`
`28.
`
`A computer program product, comprising:
`
`a computer readable medium, comprising:
`
`code for causing at least one computer to associate a plurality of carriers
`
`utilized for communication into one or more timing groups ofcarriers:
`
`code for causing the at least one computerto assign a candidate carrier in
`
`at least one of the one or more timing groupsfor timing updates;
`
`code for causing the at least one computer to receive a timing offset from
`
`the candidate carrier during a timing update; and
`
`code for causing the at least one computer to update timing for each
`
`carrier in the at least one timing group based onthe timing offset.
`
`29.
`
`The computer program product of claim 28, wherein assigning the
`
`candidate carrier includes selecting the candidate carrier according to a hash function.
`
`30.
`
`The computer program product of claim 29, wherein the hash function
`
`utilizes a variable key such that
`
`the candidate carrier differs for disparate timing
`
`updates.
`
`7
`
`

`

`DOCKETNO, 092546P1
`
`20
`
`31.
`
`The computer program product of claim 28, wherein assigning the
`
`candidate carrier is performed according to a received assignment from a basestation
`
`associated with a subset of the plurality of carriers.
`
`32.
`
`The computer program product of claim 28, wherein associating the
`
`plurality of carriers into one or more timing groups includes evaluating a timing
`
`difference of each of the plurality of carriers and grouping the plurality of carriers
`
`according to a threshold difference.
`
`33.
`
`The computer program product of claim 28, wherein associating the
`
`plurality of carriers into one or more timing groups is performed according to a
`
`grouping received from a base station associated with a subset of the plurality of
`carriers.
`
`34.
`
`The computer program product of claim 28, wherein the computer-
`
`readable medium further comprises:
`
`code for causing the at least one computer to monitor a downlink timing for each
`
`carrier in the at least one timing group; and
`
`code for causing the at least one computer to modify the timing offset according
`
`to an average of the offset applied to the monitored downlink timings for each carrier.
`
`35.
`
`The computer program product of claim 28, wherein carriers in the at
`
`least one of the one or more timing groups are transmitted at a commonsite,
`
`36,
`
`The computer program product of claim 35, wherein the timing offset is
`
`received in a vector of a plurality of timing offsets for the at least one of the one or more
`
`timing groups from the common site.
`
`8
`
`

`

`Electronic AcknowledgementReceipt
`
`5554918
`EFS ID:
`
`
`61218769
`Application Number:
`
`
`International Application Number:
`
`Confirmation Number:
`
`
`Title of Invention:
`
`TIMING ALIGNMENT IN A MULTICARRIER SYSTEM
`
`Nathan E. Tenny
`First Named Inventor/Applicant Name:
`
`23696
`Customer Number:
`
`
`Filer:
`
`Filer Authorized By:
`
`Florin C. Corie
`
`Paymentinformation: Submitted with Payment
`Florin C, Corie/Susan Turner
`
` Attorney Docket Number:
`
`092546P1
`
`
`Receipt Date:
`
`19-JUN-2009
`
`Filing Date:
`
`Time Stamp:
`
`17:36:48
`
`
`
`Application Type: Provisional
`
`Payment Type
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`Payment was successfully received in RAM
`RAM confirmation Number
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`Deposit Account
`Authorized User
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`yes
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`Deposit Account
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`$220
`
`The Director of the USPTO is hereby authorized to charge indicated fees and credit any overpayment as follows:
`
`Charge any Additional Fees required under 37 C.F.R. Section 1.21 (Miscellaneous fees and charges)
`
`9
`
`

`

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`092546P1_20090619_ADSsign
`gi
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`Application Data Sheet
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`Specification
`
`092546P1_20090619_APP.pdf
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`COMB9 te) terSeeTibetTataGelateel
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` This Acknowledgement Receipt evidences receipt on the noted date by the USPTO of the indicated documents,
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`11
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`11
`
`

`

`DOCKET NO, 092546P1
`
`1. Scope
`
`Appendix A
`
`This document describes solutions to several issues that arise in relation to maintaining timing
`synchronisation for a UE in a multicarrier LTE-Advanced (LTE-A) system.
`
`2. Background
`
`Ina single-carrier environment, the maintenance of timing synchronisation for a UE is well
`understood; the UE receives an uplink/downlink offset from the network, which occasionally
`needs to be updated, indicating how it shouldalignits uplink transmissions inrelation to the
`received downlink timing.
`
`In a multicarrier environment, however, the situationis less straightforward. Assumingthatall
`carriers serving a single UE are transmitted fromthe samecell site, it appears that a common
`offset should be adequate; however, even co-sited carriers could experience some variation in
`timing for a number of reasons (e.g., cable delays, distance between the basestation site anda
`remote radio head), which would make separate timing offsets per carrier beneficial or even
`necessary.
`
`3. Proposal
`
`3.1. Timing groups
`
`As a general framework, we propose that it should be possible to assign a UE to at least one so-
`called timing group, i.c., a group of carriers with uplink timings that are the same to within some
`tolerance. Depending onthe tolerance, a timing group might consist of carriers that share a
`common controlling site (but may still have fine differences in timing), or only of carriers whose
`antennae are collocated. Different carriers with synchronised downlinks butsignificant
`differences in uplink timing for a given UE (e.g., from differentcell sites in a synchronous
`network) would not normally belong to the same timing groupin this sense.
`
`There is no fundamental reason to assume that a UE would be assigned carriers from only one
`timing group; in principle, a UE with enough reception and decoding capabilities couldlisten to
`several sets of carriers with independent timing. Such a situation would most obviously arise if a
`UE were assigned to carriers from differentcell sites; however, the current LTE design (with no
`soft handover), and the complexities that arise when attempting to design such a system, such a
`multiple-site assignment seems unlikely. Even so, if the tolerances defining a timing groupare
`fine, it is possible that a UE could be assigned carriers from multiple timing groups originating
`from the same cell site. An example, in which a remote radio head belonging to the eNode B
`causes somecarriers to have different timing from others, is shown in Figure 1.
`
`rs
`
`onaMw
`
`10
`11
`12
`13
`14
`
`16
`
`17
`18
`19
`20
`21
`
`23
`
`24
`25
`26
`27
`28
`29
`30
`3]
`32
`
`= WR
`
`12
`
`12
`
`

`

`DOCKET NO, 092546P1
`
`Appendix A
`
`Main eNB site
`
` Remote radio head
`
`ho
`
`aub&w
`
`14
`15
`16
`17
`
`18
`19
`20
`21
`22
`
`23
`24
`25
`26
`
`Figure 1: Two timing groups from a single eNode B
`
`In sucha case, the UE could be assigned to carriers in both groups A and B, andit would need to
`maintain timing separately for each group. This might require separate timing advance
`procedures for each group, or enhancedsignalling allowing timing maintenanceto take place for
`all groups inparallel.
`
`3.2. Carrier selection for random access
`
`Within eachtiming group, the UE may need to occasionally perform randomaccess to update its
`timing (e.g., if timing is maintained through a separate procedure for each timing group). By
`definition, this update only needs to be performed with one carrier of each timing group; and the
`issue arises of how the UE should decide which carrierthis is. At a minimum, the UE should be
`expected to behave intelligently enough not to perform unnecessary timing updates, i.e., to select
`a single carrier from the timing group to use forits timing control.
`
`In principle, random access on any carrier in the group should work, However,it is desirable to
`avoidsituations in which large numbers of UEs concentrate their randomaccess attempts on a
`particular carrier, to minimise contention on the random access channel. To this end, we suggest
`that the system could adopt either a UE-based or a network-based solution.
`
`A network-based solution is extremely simple: Whenthe UE is assigned to carriers in a particular
`timing group, the network provides the UE withinstructions regarding which carrierin that group
`to use for randomaccess. The instructions could be absolute (“always use this carrier”) or subject
`to relaxation based on conditions at the UE (“use this carrier preferentially, unless radio
`conditions on that carrier are worse than indicated by a threshold”).
`
`In a UE-based approach, each UE wouldselect a single carrier for random access for timing
`updates autonomously, based on some function that tends to distribute UEs moreor less evenly
`across the timing group. A typical example would be a hash function, in which a UE associated
`with a timing group of 7 carriers provides some input to a hash function with n possible values,
`
`= 27s
`
`13
`
`13
`
`

`

`eonawkwh—
`
`13
`14
`15
`16
`17
`
`18
`
`19
`
`2)
`22
`23
`
`24
`
`25
`
`26
`27
`
`29
`30
`
`31
`32
`
`DOCKET NO, 092546P1
`
`Appendix A
`
`and the function’s output is the index ofthe carrier of the group that the UE will (prefer to) use
`for random access. (Again, the determination of the carrier could be absolute or subject to
`modification, as with the network-based solution.) There are many options for an appropriate
`hash function; a UE identifier would be a typical input, with other values such as an eNode B
`identifier also potentially used, The inputs could bestatic or time-varying;if they are static
`(depending on characteristics of the UE and/or the serving eNode B), the UE will tend to use the
`samecarrier for randomaccess throughout its assignmentto a particular group, while if the inputs
`vary with time(e.g., through the use of an input value derived from a time measurement, or a
`counter), the UE will tend to “cycle” through the available carriers. The latter approach maybe
`preferable, since it means that coincidental “spikes” in concentration (e.g., when a particular site
`is serving a large number of UEs whoseidentities result in the same output from the hash
`function) will tend to correct themselves overtime.
`
`Other UE-baseddistribution mechanisms are feasible: for instance, instead of a fixed hash
`function, the UE could use a pseudorandomfunction to choose the carrier.
`In such a case, the
`determination could be made only at the time of carrier assignment(so that a given UE
`consistently uses the same carrier for timing) or at each request for a timing update (so that each
`UE tendsto balance its requests across the available carriers).
`
`3.3. Granularity of timing alignment
`
`Within a timing group,if all carriers are precisely aligned in both downlink anduplink timing,
`there is no ambiguity about what the “correct” timing alignment for a given UE should be.
`However, in the case of small differences betweencarrier transmission timing (e.g., due to cable
`delays), carriers with the same timing offset may nevertheless have different absolute timings.
`An example is shown in Figure 2.
`
`DL
`
`Carrier 1
`
`L2
`
`Figure 2: Ambiguous uplink timing
`
`A UE in the environment of Figure 2 could receive its timing information from either carrier | or
`carrier 2. The timings of the two carriers differ, but by less than the tolerance that the deployment
`requires for a timing group; andit follows that, depending on which carrier the UE receivedits
`last update from, a UE connected to both carriers could considerthe correct uplink timing to be at
`either ULI or UL2 inthe figure.
`
`The simplest approachis for the UE simply to apply thetiming offset to the carrier on which it
`receivedit, and assumethat the timing ofother carriers in the group is “close enough”; in terms of
`
`-3/7 -
`
`14
`
`14
`
`

`

`DOCKET NO, 092546P1
`
`Appendix A
`
`the figure, this would mean that the system considered UL] and UL? to be the same for purposes
`of uplink timing accuracy. As an alternative, however, the UE could apply the offset, not to the
`received downlink timing from the carrier that transmitted the offset, but to the average timing of
`the carriers in the timing group.
`In such a case, although the UE receivedits timing information
`from a particular carrier, it tracks the (downlink) timing of each carrier in the group separately, so
`that when a single DL/UL offset is received, the UE can apply the offset separately to cach carrier
`and take an averageofthe results to provide a “happy medium”uplink timing for use withall
`carriers in the group.
`
`Actual UL timing = (DL1 + DL2)/2 + offset
`=(UL1 + UL2)\/2
`
`||
`
`UL1
`
` DL1
`
`{4}
`
`DL2
`
`UL2
`
`Figure 3: UE averaging of uplink timing from two carriers
`
`Such an averaging behaviour could be cither a specified UE behaviour(to allow greater downlink
`tolerances within a timing group whilestill keeping the variation in uplink timing acceptable) or
`left to UE implementation.
`
`3.4. Vector timing adjustment command
`
`In the event that a UE is assigned to several timing groups that are controlled from a common
`site, it may be able to receive timing adjustments for all groups with a single interaction with the
`base station. This is essentially a signalling optimisation, in the sense that the UE couldin
`principle receive the same information by performing a separate timing adjustment for each
`group, but sending the adjustments as a vector reduces over-the-air activity, and in particular
`random access procedures, which are expensive in terms of radio resources and UE battery life.
`
`To implement such a command, the network would need to be aware ofthe timing groups in
`which the UE is assignedto at least one carrier. This knowledge could be maintained
`autonomously in the network, so that upon determining the need to signal a timing advance to a
`particular UE, the network automatically includes timing advance commandsforall appropriate
`timing groups. Alternatively, the UE could requesttiming advance values for a particular set of
`timing groups (c.g., the groups for which the UE’s time-alignment timers are within some range
`of expiring). However, the request for particular groups would represent a new MACcontrol
`element, which would needto be transmitted over the air at random access with a potentially
`
`Sap
`
`15
`
`cosahwy
`
`10
`
`11
`12
`13
`
`15
`16
`17
`18
`19
`20
`
`21
`22
`23
`24
`25
`26
`27
`28
`
`15
`
`

`

`DOCKET NO, 092546P1
`
`Appendix A
`
`significant cost in radio resources. The preferredsolution is therefore for the network to maintain
`knowledge of what timing groups require timing advance commands towards a particular UE.
`
`Ina “degenerate” form of this vector approach, the network could opt to sendonly a single timing
`advance command per MACelement, but indicate which timing group the value is associated
`with. This approach would minimise the specification impact to the concerned MAC control
`element, since the existing information only needs to be augmented by a group identifier.
`It is
`presumed that such an identifier could be sent with a small numberofbits, e.g., as an index into
`the set of timing groups with which the UE was configured. Such a mapping could be established
`by explicit signalling (in higher layers such as the RRC) at the time the UE is configured with
`particularcarriers.
`
`lL. A method of maintaining timing alignment between a mobile device and a network
`operating on a plurality of frequencies, the method comprising an association of the
`frequencies into one or more timing groups, suchthat:
`
`the carriers in cach timing group share commontransmissiontiming to within somefirst
`tolerance:
`
`a single timing advance value can be indicated to the UE for use with all the carriers in
`the group, such that the resulting uplink timing when the UE transmits with this timing
`advance value towards any carrier in the group will be sufficiently accurate for
`communication with that carrier, where “sufficiently accurate”is defined in terms of
`some secondtolerance.
`
`The method of claim 1, wherein the carriers in each timing group are transmitted from
`antennas located at a common site.
`
`The method of claim |, wherein the UE may be assigned to communicate with carriers in
`one or more timing groups.
`
`The method of claim 3, wherein the UE maintains timing synchronisation for each group
`to at least one of whose carriers it is assigned.
`
`The method of claim 1, wherein the UE may maintain timing synchronisation in
`association with a random access procedure.
`
`The method of claim 5, wherein the UE performs random accessfor timing
`synchronisation on a single carrier of the timing group for which it requires timing
`information.
`
`The method of claim 6, wherein the carrier chosen within the group for randomaccess is
`assigned to the UE by the network in advance of the random access procedure.
`
`The method ofclaim 7, wherein the carrier for randomaccess is signalled to the UE as
`part of a dedicated radio resource configuration.
`
`The method of claim 7, wherein a criterion for using the indicated carrier is provided
`along with the assignmentof the carrier.
`
`Ne
`
`CowonDikw
`
`23
`24
`
`25
`26
`
`ZY
`28
`
`29
`30
`
`31
`32
`33
`
`34
`35
`
`36
`37
`
`38
`39
`
`- 5/7 -
`
`16
`
`16
`
`

`

`DOCKET NO, 092546P1
`
`Appendix A
`
`10,
`
`I,
`
`The method of claim 9, wherein thecriterion is a minimumsignal quality threshold for
`the associatedcarrier.
`
`The method of claim 9, wherein the UE is provided with an alternative carrier to use for
`random access in case the criterion is not met by the assignedcarrier,
`
`. The method of claim 9, wherein if the criterion is not met by the assigned carrier, the UE
`determines independently which carrier to use for random access.
`
`. The method of claim 6, wherein the carrier for random access is selected independently
`by the UE.
`
`. The method of claim 13, wherein the UE selects the carricr by applying a determination
`function across the set of available carriers in the timing group.
`
`15,
`
`16.
`
`17,
`
`18.
`
`The method of claim 14, wherein the determination function is a pseudorandom function.
`
`The method of claim 14, wherein the determination function is a hash function.
`
`The method of claim 16, wherein the hash function takes an identity of the UE as an
`input.
`
`The method of claim 16, wherein the hash function takes anidentity of the network node
`controlling the carriers of the timing group as an input.
`
`. The methodof claim 16, wherein the hash function takes a time-varying value as an
`input.
`
`20.
`
`21.
`
`22.
`
`os
`
`24.
`
`25.
`
`26,
`
`The method of claim 19, wherein the time-varying value is determined by a time
`measurement froman internal source in the UE.
`
`The method of claim 19, wherein the time-varying value is modified by an arithmetic
`operation each time it is used,
`
`The methodof claim 13, wherein the UE selects the carrier at a time whenradio
`resources are assigned to it on carriers associated with the timing group.
`
`The method of claim 13, wherein the UE selects the carrier when the random access
`procedure is triggered.
`
`The method of claim 1, wherein the UE determinesits uplink timing based on an average
`of timing information froma plurality of carriers in the group.
`
`The method of claim 24, wherein the plurality of carriers in the group comprises the
`carriers within the group on which the UE has radio resources assigned.
`
`The method of claim 24, wherein the plurality of carriers in the group comprises a set of
`carriers indicated to the UE by the network.
`
`13
`14
`
`15
`16
`
`17
`18
`
`19
`20
`
`21
`22
`
`23
`
`25
`26
`
`27
`28
`
`29
`30
`
`-6/7 -
`
`17
`
`17
`
`

`

`DOCKET NO, 092546P1
`
`Appendix A
`
`21.
`
`28,
`
`29,
`
`30,
`
`31.
`
`The method of claim 3, wherein timing information for a plurality of timing groups may
`be provided to the UE in a single message.
`
`The method of claim 27, wherein the messageis a timing advance command.
`
`The method of claim 27, wherein the message contains a vector of timing adjustment
`values for different timing groups.
`
`The method of claim 27, wherein timing information is provided forall timing groups
`containing at least one carrier on which the UE has assigned radio resources.
`
`The method of claim 27, wherein timing information is provided for a proper subset of
`the timing groups containing carricrs on which the UE has assigned radio resources.
`
`. The method of claim 31, wherein the proper subset is determined based on a request from
`the UE.
`
`33.
`
`34,
`
`35.
`
`The method of claim 31, wherein the propersubset is determined by the network.
`
`The method of claim 33, whercin the message includes an indication of which timing
`groups are contained in the proper subset.
`
`The method of claim 34, whereinthe indication of which timing groups are contained in
`the proper subset relies on a mapping of group identities shared between the network and
`the UE.
`
`. The method of claim 35, wherein the mapping of groupidentities is configured in
`association with the assignment to the UE of dedicated radio resources on carriers in one
`or more of the concerned timing groups.
`
`Sk
`
`38.
`
`The method of claim 3, wherein a message directed to the UE may include timing
`information for at least one timing group other than the timing group containing the
`carrier on which the messageis transmitted.
`
`The method of claim 37, wherein an indication of the timing group to which the
`information applies is included in the message.
`
`. The method of claim 37, whercin the indication of the timing groupsrelics on a mapping
`of group identities shared between the network and the UE.
`
`40.
`
`41.
`
`The method of claim 39, wherein the mapping of groupidentities is configured in
`association with the assignment to the UE of dedicated radio resources on carriers in one
`or more of the concerned timing groups.
`
`(Corresponding apparatus claims, &c.)
`
`10
`11
`
`13
`14
`
`15
`16
`17
`
`18
`19
`
`21
`22
`23
`
`24
`25
`
`26
`27
`
`28
`29
`30
`
`31
`
`STi
`
`18
`
`18
`
`

`

`DOCKETNO, 092546P1
`
`Timing Alignment in a Multicarrier System
`
`Field
`
`BACKGROUND
`
`[0001]
`
`The present application relates generally to wireless communications, and more
`
`specifically to systems and methods for multicarrier system timing alignment.
`
`Background
`
`[0002]
`
`Wircless communication systems are widcly deployed to provide various types
`
`of communication content such as voice, data, and so on. These systems may be
`
`multiple-access systems capable of supporting communication with multiple users by
`
`sharing the available system resources (e.g., bandwidth and transmit power). Examples
`
`of such multiple-access systems
`
`include code division multiple acecss (CDMA)
`
`systems, time division multiple access (TDMA) systems, frequency division multiple
`
`access (FDMA) systems, 3GPP Long Term Evolution (LTE) systems,