3GPP TS 36.321 V8.2.0 (2008-05)
`
`Technical Specification
`
`3rd Generation Partnership Project;
`Technical Specification Group Radio Access Network;
`Evolved Universal Terrestrial Radio Access (E-UTRA)
`Medium Access Control (MAC) protocol specification
`(Release 8)
`
`
`
`
`
`The present document has been developed within the 3rd Generation Partnership Project (3GPP TM) and may be further elaborated for the purposes of 3GPP.
`
`
`The present document has not been subject to any approval process by the 3GPP Organizational Partners and shall not be implemented.
`
`This Specification is provided for future development work within 3GPP only. The Organizational Partners accept no liability for any use of this Specification.
`Specifications and reports for implementation of the 3GPP TM system should be obtained via the 3GPP Organizational Partners' Publications Offices.
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`Keywords
`UMTS, radio
`
`
`
`
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`Internet
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`Copyright Notification
`
`No part may be reproduced except as authorized by written permission.
`The copyright and the foregoing restriction extend to reproduction in all media.
`
`© 2008, 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TTA, TTC).
`All rights reserved.
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`Contents
`
`Foreword ............................................................................................................................................................5
`1
`Scope........................................................................................................................................................6
`2
`References................................................................................................................................................6
`3
`Definitions and abbreviations...................................................................................................................6
`3.1
`Definitions ......................................................................................................................................................... 6
`3.2
`Abbreviations..................................................................................................................................................... 7
`4
`General .....................................................................................................................................................8
`4.1
`Introduction........................................................................................................................................................ 8
`4.2
`MAC architecture .............................................................................................................................................. 8
`4.2.1
`MAC Entities ............................................................................................................................................... 8
`4.3
`Services.............................................................................................................................................................. 8
`4.3.1
`Services provided to upper layers ................................................................................................................ 8
`4.3.2
`Services expected from physical layer ......................................................................................................... 8
`4.4
`Functions............................................................................................................................................................ 9
`4.5
`Channel structure............................................................................................................................................... 9
`4.5.1
`Transport Channels ...................................................................................................................................... 9
`4.5.2
`Logical Channels........................................................................................................................................ 10
`4.5.3
`Mapping of Transport Channels to Logical Channels................................................................................ 10
`4.5.3.1
`Uplink mapping.................................................................................................................................... 10
`4.5.3.2
`Downlink mapping ............................................................................................................................... 11
`5
`MAC procedures ....................................................................................................................................11
`5.1
`Random Access procedure............................................................................................................................... 11
`5.1.1
`Random Access Procedure initialization.................................................................................................... 11
`5.1.2
`Random Access Resource selection........................................................................................................... 12
`5.1.3
`Random Access Preamble transmission..................................................................................................... 12
`5.1.4
`Random Access Response reception.......................................................................................................... 13
`5.1.5
`Contention Resolution................................................................................................................................ 14
`5.1.6
`Completion of the Random Access procedure ........................................................................................... 15
`5.2
`Maintenance of Uplink Time Alignment......................................................................................................... 15
`5.3
`DL-SCH data transfer ...................................................................................................................................... 16
`5.3.1
`DL Assignment reception........................................................................................................................... 16
`5.3.2
`HARQ operation ........................................................................................................................................ 16
`5.3.2.1
`HARQ Entity........................................................................................................................................ 16
`5.3.2.2
`HARQ process...................................................................................................................................... 17
`5.3.3
`Disassembly and demultiplexing................................................................................................................ 17
`5.4
`UL-SCH data transfer ...................................................................................................................................... 18
`5.4.1
`UL Grant reception .................................................................................................................................... 18
`5.4.2
`HARQ operation ........................................................................................................................................ 18
`5.4.2.1
`HARQ entity......................................................................................................................................... 18
`5.4.2.2
`HARQ process...................................................................................................................................... 19
`5.4.3
`Multiplexing and assembly ........................................................................................................................ 20
`5.4.3.1
`Logical channel prioritization............................................................................................................... 20
`5.4.3.2
`Multiplexing of MAC SDUs ................................................................................................................ 21
`5.4.4
`Scheduling Request.................................................................................................................................... 21
`5.4.5
`Buffer Status Reporting.............................................................................................................................. 21
`5.4.6
`Power Headroom Reporting....................................................................................................................... 22
`5.5
`PCH reception.................................................................................................................................................. 22
`5.6
`BCH reception ................................................................................................................................................. 23
`5.7
`Discontinuous Reception (DRX) ..................................................................................................................... 23
`5.8
`MAC reconfiguration....................................................................................................................................... 24
`5.9
`MAC Reset ...................................................................................................................................................... 24
`5.X
`Handling of unknown, unforeseen and erroneous protocol data...................................................................... 24
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`Protocol Data Units, formats and parameters.........................................................................................24
`6
`Protocol Data Units.......................................................................................................................................... 24
`6.1
`General....................................................................................................................................................... 24
`6.1.1
`MAC PDU (DL-SCH and UL-SCH).......................................................................................................... 24
`6.1.2
`MAC Control Elements.............................................................................................................................. 26
`6.1.3
`Buffer Status Report MAC Control Elements ...................................................................................... 26
`6.1.3.1
`C-RNTI MAC Control Element ........................................................................................................... 26
`6.1.3.2
`DRX Command MAC Control Element............................................................................................... 26
`6.1.3.3
`UE Contention Resolution Identity MAC Control Element ................................................................. 27
`6.1.3.4
`Timing Advance MAC Control Element.............................................................................................. 27
`6.1.3.5
`Power Headroom MAC Control Element............................................................................................. 27
`6.1.3.6
`MAC PDU (transparent MAC) .................................................................................................................. 28
`6.1.4
`MAC PDU (Random Access Response) .................................................................................................... 28
`6.1.5
`Formats and parameters................................................................................................................................... 29
`6.2
`MAC header for DL-SCH and UL-SCH.................................................................................................... 29
`6.2.1
`MAC header for Random Access Response .............................................................................................. 30
`6.2.2
`MAC payload for Random Access Response ............................................................................................ 30
`6.2.3
`Variables and constants..........................................................................................................................31
`7
`RNTI values..................................................................................................................................................... 32
`7.1
`Backoff Parameter values ................................................................................................................................ 32
`7.2
`Change history ...............................................................................................33
`Annex A (informative):
`
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`Foreword
`This Technical Specification has been produced by the 3rd Generation Partnership Project (3GPP).
`
`The contents of the present document are subject to continuing work within the TSG and may change following formal
`TSG approval. Should the TSG modify the contents of the present document, it will be re-released by the TSG with an
`identifying change of release date and an increase in version number as follows:
`
`Version x.y.z
`
`where:
`
`x
`
`the first digit:
`
`1 presented to TSG for information;
`
`2 presented to TSG for approval;
`
`3 or greater indicates TSG approved document under change control.
`
`y
`
`the second digit is incremented for all changes of substance, i.e. technical enhancements, corrections,
`updates, etc.
`
`z
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`the third digit is incremented when editorial only changes have been incorporated in the document.
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`1 Scope
`The present document specifies the E-UTRA MAC protocol.
`
`References
`2
`The following documents contain provisions which, through reference in this text, constitute provisions of the present
`document.
`
`• References are either specific (identified by date of publication, edition number, version number, etc.) or
`non-specific.
`
`• For a specific reference, subsequent revisions do not apply.
`
`• For a non-specific reference, the latest version applies. In the case of a reference to a 3GPP document (including
`a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same
`Release as the present document.
`
`[1]
`
`[2]
`
`[3]
`
`[4]
`
`[5]
`
`[6]
`
`3GPP TR 21.905: "Vocabulary for 3GPP Specifications".
`
`3GPP TR 36.213: "Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Layer
`Procedures".
`
`3GPP TS 36.322: “Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Link Control
`(RLC) protocol specification”.
`
`3GPP TS 36.323: “Evolved Universal Terrestrial Radio Access (E-UTRA); Packet Data
`Convergence Protocol (PDCP) Specification”.
`
`3GPP TS 36.212: “Evolved Universal Terrestrial Radio Access (E-UTRA); Multiplexing and
`channel coding”.
`
`3GPP TS 36.214: “Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer;
`Measurements”.
`
`3
`
`Definitions and abbreviations
`
`Definitions
`3.1
`For the purposes of the present document, the terms and definitions given in TR 21.905 [1] and the following apply. A
`term defined in the present document takes precedence over the definition of the same term, if any, in TR 21.905 [1].
`
`Active Time: time during which the UE monitors the PDCCH for a PDCCH-subframe. Section 5.7 defines the
`conditions for which a subframe is included as part of Active Time.
`
`Contention Resolution Timer: Specifies the number of consecutive PDCCH-subframe(s) during which the UE shall
`monitor the PDCCH after the uplink message containing the C-RNTI MAC control element or the uplink message
`associated with UE Contention Resolution Identity submitted from higher layer is transmitted.
`
`DRX Cycle: Specifies the periodic repetition of the On Duration followed by a possible period of inactivity (see figure
`3.1-1 below).
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`Figure 3.1-1: DRX Cycle
`
`
`
`DRX Inactivity Timer: Specifies the number of consecutive PDCCH-subframe(s) after successfully decoding a
`PDCCH indicating an initial UL or DL user data transmission for this UE.
`
`DRX Retransmission Timer: Specifies the maximum number of consecutive PDCCH-subframe(s) for as soon as a DL
`retransmission is expected by the UE.
`
`DRX Short Cycle Timer: This parameter specifies the number of consecutive subframe(s)the UE shall follow the short
`DRX cycle after the DRX Inactivity Timer has expired.
`
`HARQ RTT Timer: This parameter specifies the minimum amount of subframe(s) before a DL HARQ retransmission
`is expected by the UE.
`
`On Duration Timer: Specifies the number of consecutive PDCCH-subframe(s) at the beginning of a DRX Cycle.
`
`RA-RNTI: The Random Access RNTI is used on the PDCCH when Random Access Response messages are
`transmitted. It unambiguously identifies which time-frequency resource was utilized by the UE to transmit the Random
`Access preamble.
`
`PDCCH-subframe: For FDD UE operation, this represents any subframe; for TDD, only downlink subframes.
`
`NOTE: A timer is running once it is started, until it is stopped or until it expires.
`
`NOTE: When defining On Duration Timer, DRX Inactivity Timer, DRX Retransmission Timer and Contention
`Resolution Timer, PDCCH-subframes and subframes including DwPTS are considered as subframes
`where the timer, if running, shall be updated.
`
`Abbreviations
`3.2
`For the purposes of the present document, the abbreviations given in TR 21.905 [1] and the following apply. An
`abbreviation defined in the present document takes precedence over the definition of the same abbreviation, if any, in
`TR 21.905 [1].
`
`BSR
`C-RNTI
`CQI
`E-UTRA
`E-UTRAN
`MAC
`PHR
`P-RNTI
`RA-RNTI
`RNTI
`SI-RNTI
`SR
`SRS
`TB
`
`
`
`Buffer Status Report
`Cell RNTI
`Channel Quality Indicator
`Evolved UMTS Terrestrial Radio Access
`Evolved UMTS Terrestrial Radio Access Network
`Medium Access Control
`Power Headroom Report
`Paging RNTI
`Random Access RNTI
`Radio Network Temporary Identifier
`System Information RNTI
`Scheduling Request
`Sounding Reference Symbols
`Transport Block
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`4
`
`General
`
`Introduction
`4.1
`The objective is to describe the MAC architecture and the MAC entity from a functional point of view.
`
`MAC architecture
`4.2
`The description in this sub clause is a model and does not specify or restrict implementations.
`
`RRC is in control of configuration of MAC.
`
`4.2.1 MAC Entities
`E-UTRA defines two MAC entities; one in the UE and one in the E-UTRAN. These MAC entities handle the following
`transport channels:
`
`- Broadcast Channel (BCH);
`
`- Downlink Shared Channel (DL-SCH);
`
`- Paging Channel (PCH);
`
`- Uplink Shared Channel (UL-SCH);
`
`- Random Access Channel(s) (RACH).
`
`The exact functions performed by the MAC entities are different in the UE from those performed in the E-UTRAN.
`
`4.3
`
`Services
`
`Services provided to upper layers
`4.3.1
`This clause describes the different services provided by MAC sublayer to upper layers.
`
`- data transfer
`
`-
`
`radio resource allocation
`
`Services expected from physical layer
`4.3.2
`The physical layer provides the following services to MAC:
`
`- data transfer services;
`
`-
`
`-
`
`signalling of HARQ feedback;
`
`signalling of Scheduling Request;
`
`- measurements (e.g. Channel Quality Indication (CQI)).
`
`The access to the data transfer services is through the use of transport channels. The characteristics of a transport
`channel are defined by its transport format (or format set), specifying the physical layer processing to be applied to the
`transport channel in question, such as channel coding and interleaving, and any service-specific rate matching as
`needed.
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`Functions
`4.4
`The following functions are supported by MAC sublayer:
`
`- mapping between logical channels and transport channels;
`
`- multiplexing of MAC SDUs from one or different logical channels onto transport blocks (TB) to be delivered to
`the physical layer on transport channels;
`
`- demultiplexing of MAC SDUs from one or different logical channels from transport blocks (TB) delivered from
`the physical layer on transport channels;
`
`-
`
`scheduling information reporting;
`
`- error correction through HARQ;
`
`- priority handling between UEs by means of dynamic scheduling;
`
`- priority handling between logical channels of one UE;
`
`- Logical Channel prioritisation;
`
`-
`
`transport format selection.
`
`NOTE: How the multiplexing relates to the QoS of the multiplexed logical channels is FFS.
`
`The location of the different functions and their relevance for uplink and downlink respectively is illustrated in Table
`4.4-1.
`
`Multiplexing
`
`Demultiplexing
`
`Table 4.4-1: MAC function location and link direction association.
`MAC function
`UE
`eNB
`Downlink
`Mapping between logical channels and transport channels
`X
`
`X
`
`X
`X
`X
`
`
`
`X
`X
`X
`
`X
`
`X
`
`X
`
`X
`
`X
`X
`
`X
`X
`
`X
`X
`
`X
`X
`X
`
`
`X
`
`
`
`Error correction through HARQ
`
`Transport Format Selection
`Priority handling between UEs
`Priority handling between logical channels of one UE
`Logical Channel prioritisation
`Scheduling information reporting
`
`Uplink
`X
`X
`X
`
`
`X
`X
`X
`X
`X
`X
`X
`X
`
`
`
`Channel structure
`4.5
`The MAC sublayer operates on the channels defined below; transport channels are SAPs between MAC and Layer 1,
`logical channels are SAPs between MAC and RLC.
`
`Transport Channels
`4.5.1
`The transport channels used by MAC are described in Table 4.5.1-1 below.
`
`Table 4.5.1-1: Transport channels used by MAC
`Transport channel name
`Acronym
`Downlink
`Uplink
`Broadcast Channel
`BCH
`X
`
`Downlink Shared Channel
`DL-SCH
`X
`
`Paging Channel
`PCH
`X
`
`Uplink Shared Channel
`UL-SCH
`
`X
`Random Access Channel
`RACH
`
`X
`
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`Logical Channels
`4.5.2
`The MAC layer provides data transfer services on logical channels. A set of logical channel types is defined for
`different kinds of data transfer services as offered by MAC.
`
`Each logical channel type is defined by what type of information is transferred.
`
`MAC provides the control and traffic channels listed in Table 4.5.2-1 below. When MAC uses the PDCCH to indicate
`radio resource allocation, the RNTI that is mapped on the PDCCH depends on the logical channel type:
`
`- C-RNTI, Temporary C-RNTI and Semi-Persistent Scheduling C-RNTI for DCCH and DTCH;
`
`- P-RNTI for PCCH;
`
`- RA-RNTI for Random Access Response on DL-SCH;
`
`- Temporary C-RNTI for CCCH during the random access procedure;
`
`- SI-RNTI for BCCH.
`
`Table 4.5.2-1: Logical channels provided by MAC.
`Logical channel name
`Acronym
`Control channel
`Traffic channel
`Broadcast Control Channel
`BCCH
`X
`
`Paging Control Channel
`PCCH
`X
`
`Common Control Channel
`CCCH
`X
`
`Dedicated Control Channel
`DCCH
`X
`
`Dedicated Traffic Channel
`DTCH
`
`X
`
`
`
`4.5.3 Mapping of Transport Channels to Logical Channels
`The mapping of logical channels on transport channels depends on the multiplexing that is configured by RRC.
`
`Uplink mapping
`4.5.3.1
`The MAC entity is responsible for mapping logical channels for the uplink onto uplink transport channels. The uplink
`logical channels can be mapped as described in Figure 4.5.3.1-1 and Table 4.5.3.1-1.
`
`CCCH
`
`DCCH
`
`DTCH
`
`Uplink
`Logical channels
`
`RACH
`
`UL-SCH
`
`Uplink
`Transport channels
`
`
`
`Figure 4.5.3.1-1
`
`Table 4.5.3.1-1: Uplink channel mapping.
`Transport channel
`UL-SCH
`
`Logical channel
`CCCH
`DCCH
`DTCH
`
`X
`X
`X
`
`RACH
`
`
`
`
`
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`Downlink mapping
`4.5.3.2
`The MAC entity is responsible for mapping the downlink logical channels to downlink transport channels. The
`downlink logical channels can be mapped as described in Figure 4.5.3.2-1 and Table 4.5.3.2-1.
`
`PCCH
`
`BCCH
`
`CCCH
`
`DCCH
`
`DTCH
`
`Downlink
`Logical channels
`
`PCH
`
`BCH
`
`DL-SCH
`
`Figure 4.5.3.2-1
`
`Downlink
`Transport channels
`
`
`
`Table 4.5.3.2-1: Downlink channel mapping.
`Transport channel
`BCH
`PCH
`
`Logical channel
`BCCH
`PCCH
`CCCH
`DCCH
`DTCH
`
`
`X
`
`
`
`
`X
`
`
`
`
`
`DL-SCH
`
`X
`
`X
`X
`X
`
`MAC procedures
`
`
`
` 5
`
`5.1
`
`Random Access procedure
`
`Random Access Procedure initialization
`5.1.1
`The Random Access procedure described in this subclause is initiated by a PDCCH order or by the MAC sublayer
`itself. The PDCCH order or RRC optionally indicate a Random Access Preamble and PRACH resource.
`
`Before the procedure can be initiated, the following information is assumed to be available:
`
`-
`
`-
`
`-
`
`-
`
`-
`
`-
`
`-
`
`-
`
`the available set of PRACH resources for the transmission of the Random Access Preamble and their
`corresponding RA-RNTIs.
`
`the groups of Random Access Preambles and the set of available Random Access Preambles in each group.
`
`the thresholds required for selecting one of the two groups of Random Access Preambles.
`
`the parameters required to derive the TTI window described in subclause 5.1.4.
`
`the power-ramping factor POWER_RAMP_STEP.
`
`the parameter PREAMBLE_TRANS_MAX [integer > 0].
`
`the initial preamble power PREAMBLE_ INITIAL_RECEIVED_TARGET_POWER.
`
`the parameter Maximum number of Message3 HARQ transmissions.
`
`[Note that the above parameters may be updated from higher layers before each Random Access procedure is initiated.]
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`The Random Access procedure shall be performed as follows:
`
`- Flush the [Message3] buffer;
`
`-
`
`-
`
`set the PREAMBLE_TRANSMISSION_COUNTER to 1;
`
`set the backoff parameter value in the UE to 0 ms;
`
`- proceed to the selection of the Random Access Resource (see subclause 5.1.2).
`
`NOTE: There is only one Random Access procedure ongoing at any point in time. If the UE receives a request for
`a new Random Access procedure while another is already ongoing, it is up to UE implementation whether
`to continue with the ongoing procedure or start with the new procedure.
`
`Random Access Resource selection
`5.1.2
`The Random Access Resource procedure shall be performed as follows:
`
`-
`
`If the Random Access Preamble and PRACH resource have been explicitly signalled and the Random Access
`Preamble expiration time, if configured, has not expired:
`
`-
`
`the UE can directly proceed to the transmission of the Random Access Preamble (see subclause 5.1.3).
`
`- else the Random Access Preamble shall be selected by the UE as follows:
`
`-
`
`If the uplink message containing the C-RNTI MAC control element or the uplink message including the
`CCCH SDU has not yet been transmitted, the UE shall:
`
`- depending on the size of the message to be transmitted on the UL or the requested resource blocks [FFS]
`[the selection also depends on radio conditions], select one of the two groups of Random Access
`Preambles configured by RRC.
`
`- else, if the uplink message containing the C-RNTI MAC control element or the uplink message including the
`CCCH SDU is being retransmitted, the UE shall:
`
`-
`
`select the same group of Random Access Preambles as was used for the preamble transmission attempt
`corresponding to the first transmission of the uplink message containing the C-RNTI MAC control
`element or the uplink message including the CCCH SDU.
`
`randomly select a Random Access Preamble within the selected group. The random function shall be such
`that each of the allowed selections can be chosen with equal probability;
`
`if more than one PRACH resources are available in the same subframe (TDD), randomly select one. The
`random function shall be such that each of the allowed selections can be chosen with equal probability;
`
`-
`
`-
`
`- proceed to the transmission of the Random Access Preamble (see subclause 5.1.3).
`
`Random Access Preamble transmission
`5.1.3
`The random-access procedure shall be performed as follows:
`
`-
`
`If PREAMBLE_TRANSMISSION_COUNTER = PREAMBLE_TRANS_MAX + 1:
`
`-
`
`indicate a Random Access problem to upper layers.
`
`[- set the parameter PREAMBLE_RECEIVED_TARGET_POWER to
`PREAMBLE_INITIAL_RECEIVED_TARGET_POWER + (PREAMBLE_TRANSMISSION_COUNTER-1) *
`POWER_RAMP_STEP;]
`
`- determine the next available Random Access occasion;
`
`-
`
`instruct the physical layer to transmit a preamble using the selected PRACH resource, corresponding RA-RNTI,
`preamble index and PREAMBLE_RECEIVED_TARGET_POWER.
`
`3GPP
`
`SAMSUNG 1003-0012
`
`

`

`
`Release 8
`
`13
`
`3GPP TS 36.321 V8.2.0 (2008-05)
`
`Random Access Response reception
`5.1.4
`Once the Random Access Preamble is transmitted, the UE shall monitor the PDCCH associated with the RA-RNTI
`defined below in the TTI window [RA_WINDOW_BEGIN—RA_WINDOW_END] for Random Access Response(s)
`identified by the RA-RNTI. The RA-RNTI associated with the PRACH resource in which the Random Access
`Preamble is transmitted, is computed as:
`
`RA-RNTI= t_id+10*f_id
`
`Where t_id is the index of the first subframe of the specified PRACH resource (0≤ t_id <10), and f_id is the index of the
`specified PRACH resource within that subframe, in ascending order of frequency domain (0≤ f_id< 6). The UE may
`stop monitoring for Random Access Response(s) after successful reception of a Random Access Response
`corresponding to the Random Access Preamble transmission.
`
`-
`
`If notification of a reception of the Random Access Response is received from lower layers, the UE shall:
`
`-
`
`if the Random Access Response contains a Backoff Indicator subheader:
`
`-
`
`set the backoff parameter value in the UE as indicated by the BI field of the Backoff Indicator subheader
`and Table 7.2-1.
`
`- else, set the backoff parameter value in the UE to 0 ms.
`
`-
`
`if the Random Access Response contains a Random Access Preamble identifier corresponding to the
`transmitted Random Access Preamble (see subclause 5.1.3), the UE shall:
`
`- consider this Random Access Response reception successful;
`
`- process the received Timing Alignment value (see subclause 5.2);
`
`- process the received UL grant value;
`
`-
`
`if the Random Access Preamble was explicitly signalled (i.e., not selected by MAC):
`
`- consider the Random Access procedure successfully completed.
`
`- else, if the Random Access Preamble was selected by UE MAC:
`
`-
`
`-
`
`set the Temporary C-RNTI to the value received in the Random Access Response message no later
`than at the time of the first transmission corresponding to the UL grant provided in the Random
`Access Response message;
`
`if this is the first successfully received Random Access Response within this Random Access
`procedure:
`
`-
`
`if the UE is in RRC_CONNECTED state [except for RLF], indicate to the Multiplexing and
`assembly entity to include a C-RNTI MAC control element in the subsequent uplink transmission;
`
`- obtain the MAC PDU to transmit from the "Multiplexing and assembly" entity and store it in the
`[Message3] buffer.
`
`NOTE: When an uplink transmission is required, e.g., for contention resolution, the eNB should not provide a
`grant smaller than 80 bits in the Random Access Response.
`
`NOTE:
`
`If within a Random Access procedure, an uplink grant provided in the Random Access Response for the
`same group of Random Access Preambles has a different size than the first uplink grant allocated during
`that Random Access procedure, the UE behavior is not defined.
`
`If no Random Access Response is received within the TTI window [RA_WINDOW_BEGIN—RA_WINDOW_END],
`or if all received Random Access Responses contain Random Access Preamble identifiers that do not match the
`transmitted Random Access Preamble, the Random Access Response reception is considered not successful and the UE
`shall:
`
`-
`
`if the Random Access procedure was initiated by the MAC sublayer itself; or
`
`3GPP
`
`SAMSUNG 1003-0013
`
`

`

`
`Release 8
`
`14
`
`3GPP TS 36.321 V8.2.0 (2008-05)
`
`-
`
`if the Random Access procedure was initiated by a PDCCH order and the
`PREAMBLE_TRANSMISSION_COUNTER is less than PREAMBLE_TRANS_MAX:
`
`-
`
`-
`
`increment PREAMBLE_TRANSMISSION_COUNTER by 1;
`
`if in this Random Access procedure:
`
`-
`
`-
`
`the Random Access Preamble was selected by MAC; or
`
`the Random Access Preamble and PRACH resource were explicitly signalled and will expire before the
`next available Random Acces