ETSI TS 136 321 V12.10.0 (2017-10)

LTE; Evolved Universal Terrestrial Radio Access (E-UTRA); Medium Access Control (MAC) protocol specification (3GPP TS 36.321 version 12.10.0 Release 12)

RTS/TSGR-0236321vca0

General Information

• Status: Published
• Publication Date: 08-Oct-2017
• Technical Committee: 3GPP RAN 2 - Radio layer 2 specification and Radio layer 3 RR specification
• Current Stage: 12 - Completion
• Completion Date: 09-Oct-2017

Standards Content (Sample)

TECHNICAL SPECIFICATION
LTE;
Evolved Universal Terrestrial Radio Access (E-UTRA);
Medium Access Control (MAC) protocol specification
(3GPP TS 36.321 version 12.10.0 Release 12)

3GPP TS 36.321 version 12.10.0 Release 12 1 ETSI TS 136 321 V12.10.0 (2017-10)

Reference
RTS/TSGR-0236321vca0
Keywords
LTE
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3GPP TS 36.321 version 12.10.0 Release 12 2 ETSI TS 136 321 V12.10.0 (2017-10)
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Foreword
This Technical Specification (TS) has been produced by ETSI 3rd Generation Partnership Project (3GPP).
The present document may refer to technical specifications or reports using their 3GPP identities, UMTS identities or
GSM identities. These should be interpreted as being references to the corresponding ETSI deliverables.
The cross reference between GSM, UMTS, 3GPP and ETSI identities can be found under
http://webapp.etsi.org/key/queryform.asp.
Modal verbs terminology
In the present document "shall", "shall not", "should", "should not", "may", "need not", "will", "will not", "can" and
"cannot" are to be interpreted as described in clause 3.2 of the ETSI Drafting Rules (Verbal forms for the expression of
provisions).
"must" and "must not" are NOT allowed in ETSI deliverables except when used in direct citation.
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Contents
Intellectual Property Rights . 2
Foreword . 2
Modal verbs terminology . 2
Foreword . 6
1 Scope . 7
2 References . 7
3 Definitions and abbreviations . 8
3.1 Definitions . 8
3.2 Abbreviations . 9
4 General . 10
4.1 Introduction . 10
4.2 MAC architecture . 10
4.2.1 MAC Entities . 10
4.3 Services . 13
4.3.1 Services provided to upper layers . 13
4.3.2 Services expected from physical layer . 13
4.4 Functions . 13
4.5 Channel structure . 14
4.5.1 Transport Channels . 14
4.5.2 Logical Channels . 14
4.5.3 Mapping of Transport Channels to Logical Channels . 15
4.5.3.1 Uplink mapping . 15
4.5.3.2 Downlink mapping . 15
4.5.3.3 Sidelink mapping . 16
5 MAC procedures . 17
5.1 Random Access procedure . 17
5.1.1 Random Access Procedure initialization . 17
5.1.2 Random Access Resource selection . 18
5.1.3 Random Access Preamble transmission . 19
5.1.4 Random Access Response reception. 19
5.1.5 Contention Resolution . 20
5.1.6 Completion of the Random Access procedure . 21
5.2 Maintenance of Uplink Time Alignment . 22
5.3 DL-SCH data transfer . 23
5.3.1 DL Assignment reception . 23
5.3.2 HARQ operation . 24
5.3.2.1 HARQ Entity. 24
5.3.2.2 HARQ process . 25
5.3.3 Disassembly and demultiplexing . 26
5.4 UL-SCH data transfer . 26
5.4.1 UL Grant reception . 26
5.4.2 HARQ operation . 27
5.4.2.1 HARQ entity . 27
5.4.2.2 HARQ process . 28
5.4.3 Multiplexing and assembly . 30
5.4.3.1 Logical channel prioritization . 30
5.4.3.2 Multiplexing of MAC Control Elements and MAC SDUs . 31
5.4.4 Scheduling Request. 31
5.4.5 Buffer Status Reporting . 31
5.4.6 Power Headroom Reporting . 33
5.5 PCH reception . 35
5.6 BCH reception . 35
5.7 Discontinuous Reception (DRX) . 35
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5.8 MAC reconfiguration . 37
5.9 MAC Reset . 37
5.10 Semi-Persistent Scheduling . 37
5.10.1 Downlink . 38
5.10.2 Uplink . 38
5.11 Handling of unknown, unforeseen and erroneous protocol data . 39
5.12 MCH reception . 39
5.13 Activation/Deactivation of SCells . 39
5.14 SL-SCH Data transfer . 40
5.14.1 SL-SCH Data transmission . 40
5.14.1.1 SL Grant reception and SCI transmission . 40
5.14.1.2 Sidelink HARQ operation . 41
5.14.1.2.1 Sidelink HARQ Entity . 41
5.14.1.2.2 Sidelink process . 41
5.14.1.3 Multiplexing and assembly . 42
5.14.1.3.1 Logical channel prioritization . 42
5.14.1.3.2 Multiplexing of MAC SDUs . 42
5.14.1.4 Buffer Status Reporting . 43
5.14.2 SL-SCH Data reception . 44
5.14.2.1 SCI reception. 44
5.14.2.2 Sidelink HARQ operation . 45
5.14.2.2.1 Sidelink HARQ Entity . 45
5.14.2.2.2 Sidelink process . 45
5.14.2.3 Disassembly and demultiplexing . 46
5.15 SL-DCH data transfer . 46
5.15.1 SL-DCH data transmission . 46
5.15.1.1 Resource allocation . 46
5.15.1.2 Sidelink HARQ operation . 46
5.15.1.2.1 Sidelink HARQ Entity . 46
5.15.1.2.2 Sidelink process . 47
5.15.2 SL-DCH data reception . 48
5.15.2.1 Sidelink HARQ operation . 48
5.15.2.1.1 Sidelink HARQ Entity . 48
5.15.2.1.2 Sidelink process . 48
5.16 SL-BCH data transfer . 49
5.16.1 SL-BCH data transmission . 49
5.16.2 SL-BCH data reception . 49
6 Protocol Data Units, formats and parameters . 49
6.1 Protocol Data Units . 49
6.1.1 General . 49
6.1.2 MAC PDU (DL-SCH and UL-SCH except transparent MAC and Random Access Response, MCH) . 49
6.1.3 MAC Control Elements . 50
6.1.3.1 Buffer Status Report MAC Control Elements . 50
6.1.3.1a Sidelink BSR MAC Control Elements . 53
6.1.3.2 C-RNTI MAC Control Element . 54
6.1.3.3 DRX Command MAC Control Element . 55
6.1.3.4 UE Contention Resolution Identity MAC Control Element . 55
6.1.3.5 Timing Advance Command MAC Control Element . 55
6.1.3.6 Power Headroom Report MAC Control Element . 55
6.1.3.6a Extended Power Headroom Report MAC Control Element . 56
6.1.3.6b Dual Connectivity Power Headroom Report MAC Control Element . 57
6.1.3.7 MCH Scheduling Information MAC Control Element . 58
6.1.3.7a Extended MCH Scheduling Information MAC Control Element . 59
6.1.3.8 Activation/Deactivation MAC Control Element . 60
6.1.3.9 Long DRX Command MAC Control Element . 60
6.1.4 MAC PDU (transparent MAC) . 60
6.1.5 MAC PDU (Random Access Response) . 60
6.1.6 MAC PDU (SL-SCH) . 61
6.2 Formats and parameters . 63
6.2.1 MAC header for DL-SCH, UL-SCH and MCH. 63
6.2.2 MAC header for Random Access Response . 64
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6.2.3 MAC payload for Random Access Response . 65
6.2.4 MAC header for SL-SCH . 65
7 Variables and constants . 66
7.1 RNTI values . 66
7.2 Backoff Parameter values . 67
7.3 PRACH Mask Index values. 67
7.4 Subframe_Offset values . 67
7.5 TTI_BUNDLE_SIZE value. 68
7.6 DELTA_PREAMBLE values . 68
7.7 HARQ RTT Timer . 68
Annex A (normative): Handling of measurement gaps . 69
Annex B (normative): Contention resolution for RACH access . 70
Annex C (informative): Intended UE behaviour for DRX Timers . 71
Annex D (informative): Change history . 72
History . 77

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Foreword
rd
This Technical Specification has been produced by the 3 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 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.
2 References
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] 3GPP TR 21.905: "Vocabulary for 3GPP Specifications".
[2] 3GPP TS 36.213: "Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Layer
Procedures".
[3] 3GPP TS 36.322: “Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Link Control
(RLC) protocol specification”.
[4] 3GPP TS 36.323: “Evolved Universal Terrestrial Radio Access (E-UTRA); Packet Data
Convergence Protocol (PDCP) Specification”.
[5] 3GPP TS 36.212: “Evolved Universal Terrestrial Radio Access (E-UTRA); Multiplexing and
channel coding”.
[6] 3GPP TS 36.214: “Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer;
Measurements”.
[7] 3GPP TS 36.211: “Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Channels
and Modulation”.
[8] 3GPP TS 36.331: “Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource
Control (RRC); Protocol specification”.
[9] 3GPP TS 36.133: "Evolved Universal Terrestrial Radio Access (E-UTRA); Requirements for
support of radio resource management".
[10] 3GPP TS 36.101: "Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE)
radio transmission and reception".
[11] 3GPP TS 36.216: "Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer for
relaying operation".
[12] 3GPP TS 36.306: "Evolved Universal Terrestrial Radio Access (E-UTRA); User Equipment (UE)
radio access capabilities".
[13] 3GPP TS 23.303: "Proximity-based services (ProSe); Stage 2".
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3 Definitions and abbreviations
3.1 Definitions
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 related to DRX operation, as defined in subclause 5.7, during which the MAC entity monitors the
PDCCH.
mac-ContentionResolutionTimer: Specifies the number of consecutive subframe(s) during which the MAC entity shall
monitor the PDCCH after Msg3 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).
Figure 3.1-1: DRX Cycle
drx-InactivityTimer: Specifies the number of consecutive PDCCH-subframe(s) after the subframe in which a PDCCH
indicates an initial UL, DL or SL user data transmission for this MAC entity.
drx-RetransmissionTimer: Specifies the maximum number of consecutive PDCCH-subframe(s) until a DL
retransmission is received.
drxShortCycleTimer: Specifies the number of consecutive subframe(s) the MAC entity shall follow the Short DRX
cycle.
drxStartOffset: Specifies the subframe where the DRX Cycle starts.
HARQ information: HARQ information for DL-SCH or for UL-SCH transmissions consists of New Data Indicator
(NDI), Transport Block (TB) size. For DL-SCH transmissions the HARQ information also includes HARQ process ID.
For UL-SCH transmission the HARQ information also includes Redundancy Version (RV). In case of spatial
multiplexing on DL-SCH the HARQ information comprises a set of NDI and TB size for each transport block. HARQ
information for SL-SCH and SL-DCH transmissions consists of TB size only.
HARQ RTT Timer: This parameter specifies the minimum amount of subframe(s) before a DL HARQ retransmission
is expected by the MAC entity.
Msg3: Message transmitted on UL-SCH containing a C-RNTI MAC CE or CCCH SDU, submitted from upper layer
and associated with the UE Contention Resolution Identity, as part of a random access procedure.
onDurationTimer: Specifies the number of consecutive PDCCH-subframe(s) at the beginning of a DRX Cycle.
PDCCH: Refers to the PDCCH [7], EPDCCH (in subframes when configured) or, for an RN with R-PDCCH
configured and not suspended, to the R-PDCCH.
PDCCH-subframe: Refers to a subframe with PDCCH. For a MAC entity configured with only FDD serving cell(s),
this represents any subframe; for a MAC entity configured with at least one TDD serving cell, if a MAC entity is
capable of simultaneous reception and transmission in the aggregated cells, this represents the union over all serving
cells of downlink subframes and subframes including DwPTS of the TDD UL/DL configuration indicated by tdd-
Config [8], except serving cells that are configured with schedulingCellId [8]; otherwise, this represents the subframes
where the SpCell is configured with a downlink subframe or a subframe including DwPTS of the TDD UL/DL
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configuration indicated by tdd-Config [8].
For RNs with an RN subframe configuration configured and not suspended, in its communication with the E-UTRAN,
this represents all downlink subframes configured for RN communication with the E-UTRAN.
PRACH Resource Index: The index of a PRACH within a system frame [7]
Primary Timing Advance Group: Timing Advance Group containing the SpCell.
ra-PRACH-MaskIndex: Defines in which PRACHs within a system frame the MAC entity can transmit a Random
Access Preamble (see subclause 7.3).
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 MAC entity to transmit the
Random Access preamble.
SC Period: Sidelink Control period, the time period consisting of transmission of SCI and its corresponding data.
SCI: The Sidelink Control Information contains the sidelink scheduling information such as resource block assignment,
modulation and coding scheme and Group Destination ID [5].
Secondary Timing Advance Group: Timing Advance Group not containing the SpCell. A Secondary Timing Advance
Group contains at least one Serving Cell with an UL configured.
Serving Cell: A Primary or a Secondary Cell [8].
Sidelink: UE to UE interface for sidelink communication and sidelink discovery. The sidelink corresponds to the PC5
interface as defined in [13].
Special Cell: For Dual Connectivity operation the term Special Cell refers to the PCell of the MCG or the PSCell of the
SCG, otherwise the term Special Cell refers to the PCell.
Timing Advance Group: A group of Serving Cells that is configured by RRC and that, for the cells with an UL
configured, using the same timing reference cell and the same Timing Advance value.
NOTE: A timer is running once it is started, until it is stopped or until it expires; otherwise it is not running. A
timer can be started if it is not running or restarted if it is running. A Timer is always started or restarted
from its initial value.
3.2 Abbreviations
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  Buffer Status Report
C-RNTI  Cell RNTI
CQI  Channel Quality Indicator
eIMTA  Enhanced Interference Management and Traffic Adaptation
eIMTA-RNTI  Enhanced Interference Management and Traffic Adaptation - RNTI
E-UTRA  Evolved UMTS Terrestrial Radio Access
E-UTRAN  Evolved UMTS Terrestrial Radio Access Network
MAC  Medium Access Control
MCG  Master Cell Group
M-RNTI  MBMS RNTI
LCG  Logical Channel Group
PCell  Primary Cell
PSCell  Primary Secondary Cell
PHR  Power Headroom Report
PMI  Precoding Matrix Index
P-RNTI  Paging RNTI
ProSe  Proximity-based Services
pTAG  Primary Timing Advance Group
PTI  Precoding Type Indicator
RA-RNTI  Random Access RNTI
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RI  Rank Indicator
RN  Relay Node
RNTI  Radio Network Temporary Identifier
SCell  Secondary Cell
SCG  Secondary Cell Group
SCI  Sidelink Control Information
SI-RNTI  System Information RNTI
SL  Sidelink
SL-RNTI  Sidelink RNTI
SR  Scheduling Request
SRS  Sounding Reference Symbols
SpCell  Special Cell
sTAG  Secondary Timing Advance Group
TAG  Timing Advance Group
TB  Transport Block
TPC-PUCCH-RNTI Transmit Power Control-Physical Uplink Control Channel-RNTI
TPC-PUSCH-RNTI Transmit Power Control-Physical Uplink Shared Channel-RNTI
4 General
4.1 Introduction
The objective is to describe the MAC architecture and the MAC entity from a functional point of view. Functionality
specified for the UE equally applies to the RN for functionality necessary for the RN. There is also functionality which
is only applicable to the RN, in which case the specification denotes the RN instead of the UE. RN-specific behaviour is
not applicable to the UE. For TDD operation, UE behaviour follows the TDD UL/DL configuration indicated by tdd-
Config unless specified otherwise.
4.2 MAC architecture
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(s) (DL-SCH);
- Paging Channel (PCH);
- Uplink Shared Channel(s) (UL-SCH);
- Random Access Channel(s) (RACH);
- Multicast Channel(s) (MCH);
- Sidelink Broadcast Channel (SL-BCH);
- Sidelink Discovery Channel (SL-DCH);
- Sidelink Shared Channel (SL-SCH).
The exact functions performed by the MAC entities are different in the UE from those performed in the E-UTRAN.
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The RN includes both types of MAC entities; one type for communication with UEs and one type for communication
with the E-UTRAN.
In Dual Connectivity, two MAC entities are configured in the UE: one for the MCG and one for the SCG. Each MAC
entity is configured by RRC with a serving cell supporting PUCCH transmission and contention based Random Access.
In this specification, the term SpCell refers to such cell, whereas the term SCell refers to other serving cells. The term
SpCell either refers to the PCell of the MCG or the PSCell of the SCG depending on if the MAC entity is associated to
the MCG or the SCG, respectively. A Timing Advance Group containing the SpCell of a MAC entity is referred to as
pTAG, whereas the term sTAG refers to other TAGs.
The functions of the different MAC entities in the UE operate independently if not otherwise indicated. The timers and
paramenters used in each MAC entity are configured independently if not otherwise indicated. The Serving Cells, C-
RNTI, radio bearers, logical channels, upper and lower layer entities, LCGs, and HARQ entities considered by each
MAC entity refer to those mapped to that MAC entity if not otherwise indicated.
If the MAC entity is configured with one or more SCells, there are multiple DL-SCH and there may be multiple UL-
SCH and RACH per MAC entity; one DL-SCH and UL-SCH on the SpCell, one DL-SCH, zero or one UL-SCH and
zero or one RACH for each SCell.
Figure 4.2.1-1 illustrates one possible structure for the UE side MAC entity when SCG is not configured, and it should
not restrict implementation.
Figure 4.2.1-1: MAC structure overview, UE side
Figure 4.2.1-2 illustrates one possible structure for the UE side MAC entities when MCG and SCG are configured, and
it should not restrict implementation. MBMS reception is excluded from this figure for simplicity.
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Figure 4.2.1-2: MAC structure overview with two MAC entities, UE side
Figure 4.2.1-3 illustrates one possible structure for the UE side MAC entity when sidelink is configured, and it should
not restrict implementation.
Upper layers
MAC-control
SBCCH STCH
Logical Channel
Prioritization (tx
only)
(De-)Multiplexing
Control
PDU filtering
(rx only)
HARQ HARQ
SL-BCH SL-SCH
SL-DCH
Lower layer
Figure 4.2.1-3: MAC structure overview for sidelink, UE side
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4.3 Services
4.3.1 Services provided to upper layers
This clause describes the different services provided by MAC sublayer to upper layers.
- data transfer
- radio resource allocation
4.3.2 Services expected from physical layer
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.
4.4 Functions
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 MAC entity;
- Logical Channel prioritisation;
- transport format selection;
- radio resource selection for SL.
The location of the different functions and their relevance for uplink and downlink respectively is illustrated in Table
4.4-1.
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Table 4.4-1: MAC function location and link direction association.
MAC function UE eNB Downlink Uplink Sidelink tx Sidelink rx
Mapping between logical channels and transport channels X X X X X
X X X
Multiplexing X  X X
X X
Demultiplexing X X  X
X X
Error correction through HARQ X X X X X
X X X
Transport Format Selection X X X
X X  X
Priority handling between UEs X X X
Priority handling between logical channels of one MAC X X X
entity
Logical Channel prioritisation X  X X
Scheduling information reporting X  X
Radio Resource Selection X  X

4.5 Channel structure
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.
4.5.1 Transport Channels
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 Sidelink tx Sidelink rx
Broadcast Channel BCH X
Downlink Shared Channel DL-SCH X
Paging Channel PCH X
Multicast Channel MCH X
Uplink Shared Channel UL-SCH X
Random Access Channel RACH X
Sidelink Broadcast SL-BCH  X X
Channel
Sidelink Discovery Channel SL-DCH  X X
Sidelink Shared Channel SL-SCH  X X

4.5.2 Logical Channels
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.
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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
Multicast Control Channel MCCH X
Dedicated Traffic Channel DTCH X
Multicast Traffic Channel MTCH X
Sidelink Traffic Channel STCH X
Sidelink Broadcast Control SBCCH X
Channel
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.
4.5.3.1 Uplink mapping
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.
CC CH DCCH DTCH
Uplink
Logical channels
Uplink
Transport channels
RACH UL-SCH
Figure 4.5.3.1-1
Table 4.5.3.1-1: Uplink channel mapping.
Transport channel UL-SCH RACH
Logical channel
CCCH X
DCCH X
DTCH X
4.5.3.2 Downlink mapping
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.
ETSI
3GPP TS 36.321 version 12.10.0 Release 12 16 ETSI TS 136 321 V12.10.0 (2017-10)

Figure 4.5.3.2-1
Table 4.5.3.2-1: Downlink channel mapping.
Transport channel BCH PCH DL-SCH MCH
Logical channel
BCCH X X
PCCH X
CCCH  X
DCCH  X
DTCH  X
MCCH  X
MTCH  X
4.5.3.3 Sidelink mapping
The MAC entity is responsible for mapping the sidelink logical channels to sidelink transport channels. The sidelink
logical channels can be mapped as described in Figure 4.5.3.3-1 and Table 4.5.3.3-1.
SBCCH STCH
Sidelink
Logical channels
Sidelink
Transport channels
SL-BCH SL-DCH SL-SCH
Figure 4.5.3.3-1
Table 4.5.3.3-1: Sidelink channel mapping.
Transport channel SL-SCH SL-BCH SL-DCH
Logical channel
STCH X
SBCCH X
ETSI
3GPP TS 36.321 version 12.10.0 Release 12 17 ETSI TS 136 321 V12.10.0 (2017-10)
5 MAC procedures
5.1 Random Access pr
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