ETSI TS 138 212 V18.8.0 (2026-02)

5G; NR; Multiplexing and channel coding (3GPP TS 38.212 version 18.8.0 Release 18)

RTS/TSGR-0138212vi80

General Information

• Status: Not Published
• Technical Committee: 3GPP RAN 1 - Radio layer 1 specification
• Current Stage: 12 - Citation in the OJ (auto-insert)
• Completion Date: 16-Feb-2026

Standards Content (Sample)

TECHNICAL SPECIFICATION
5G;
NR;
Multiplexing and channel coding
(3GPP TS 38.212 version 18.8.0 Release 18)

3GPP TS 38.212 version 18.8.0 Release 18 1 ETSI TS 138 212 V18.8.0 (2026-02)

Reference
RTS/TSGR-0138212vi80
Keywords
5G
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ETSI
3GPP TS 38.212 version 18.8.0 Release 18 2 ETSI TS 138 212 V18.8.0 (2026-02)
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Legal Notice
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. These shall be
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The cross reference between 3GPP and ETSI identities can be found at 3GPP to ETSI numbering cross-referencing.
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.
ETSI
3GPP TS 38.212 version 18.8.0 Release 18 3 ETSI TS 138 212 V18.8.0 (2026-02)
Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 6
1 Scope . 8
2 References . 8
3 Definitions of terms, symbols and abbreviations . 8
3.1 Terms . 8
3.2 Symbols . 8
3.3 Abbreviations . 9
4 Mapping to physical channels . 10
4.1 Uplink . 10
4.2 Downlink . 10
4.3 Sidelink . 10
5 General procedures . 11
5.1 CRC calculation . 11
5.2 Code block segmentation and code block CRC attachment . 12
5.2.1 Polar coding . 12
5.2.2 Low density parity check coding . 12
5.3 Channel coding . 14
5.3.1 Polar coding . 15
5.3.1.1 Interleaving . 15
5.3.1.2 Polar encoding . 16
5.3.2 Low density parity check coding . 19
5.3.3 Channel coding of small block lengths . 24
5.3.3.1 Encoding of 1-bit information . 24
5.3.3.2 Encoding of 2-bit information . 24
5.3.3.3 Encoding of other small block lengths . 25
5.4 Rate matching . 26
5.4.1 Rate matching for Polar code . 26
5.4.1.1 Sub-block interleaving . 26
5.4.1.2 Bit selection. 27
5.4.1.3 Interleaving of coded bits . 27
5.4.2 Rate matching for LDPC code . 28
5.4.2.1 Bit selection. 29
5.4.2.2 Bit interleaving . 32
5.4.3 Rate matching for channel coding of small block lengths . 32
5.5 Code block concatenation . 32
6 Uplink transport channels and control information . 33
6.1 Random access channel . 33
6.2 Uplink shared channel . 33
6.2.1 Transport block CRC attachment . 33
6.2.2 LDPC base graph selection . 33
6.2.3 Code block segmentation and code block CRC attachment . 34
6.2.4 Channel coding of UL-SCH. 34
6.2.5 Rate matching . 34
6.2.6 Code block concatenation . 34
6.2.7 Data and control multiplexing . 35
6.3 Uplink control information . 46
6.3.1 Uplink control information on PUCCH . 46
6.3.1.1 UCI bit sequence generation . 46
6.3.1.1.1 HARQ-ACK/SR only . 46
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3GPP TS 38.212 version 18.8.0 Release 18 4 ETSI TS 138 212 V18.8.0 (2026-02)
6.3.1.1.2 CSI only . 46
6.3.1.1.3 HARQ-ACK/SR and CSI . 64
6.3.1.1.4 UCI with different priority indexes . 65
6.3.1.2 Code block segmentation and CRC attachment . 65
6.3.1.2.1 UCI encoded by Polar code . 65
6.3.1.2.2 UCI encoded by channel coding of small block lengths . 66
6.3.1.3 Channel coding of UCI . 66
6.3.1.3.1 UCI encoded by Polar code . 66
6.3.1.3.2 UCI encoded by channel coding of small block lengths . 66
6.3.1.4 Rate matching . 66
6.3.1.4.1 UCI encoded by Polar code . 66
6.3.1.4.2 UCI encoded by channel coding of small block lengths . 67
6.3.1.4.3 UCI with different priority indexes encoded by Polar code . 68
6.3.1.4.4 UCI with different priority indexes encoded by channel coding of small block lengths . 68
6.3.1.5 Code block concatenation . 69
6.3.1.6 Multiplexing of coded UCI bits to PUCCH . 69
6.3.2 Uplink control information on PUSCH . 71
6.3.2.1 UCI bit sequence generation . 72
6.3.2.1.1 HARQ-ACK . 72
6.3.2.1.2 CSI . 72
6.3.2.1.3 CG-UCI . 94
6.3.2.1.3A UTO-UCI. 95
6.3.2.1.4 HARQ-ACK and CG-UCI/UTO-UCI . 95
6.3.2.1.5 UCI with different priority indexes . 96
6.3.2.2 Code block segmentation and CRC attachment . 98
6.3.2.2.1 UCI encoded by Polar code . 98
6.3.2.2.2 UCI encoded by channel coding of small block lengths . 98
6.3.2.3 Channel coding of UCI . 98
6.3.2.3.1 UCI encoded by Polar code . 98
6.3.2.3.2 UCI encoded by channel coding of small block lengths . 98
6.3.2.4 Rate matching . 98
6.3.2.4.1 UCI encoded by Polar code . 98
6.3.2.4.2 UCI encoded by channel coding of small block lengths . 112
6.3.2.5 Code block concatenation . 115
6.3.2.6 Multiplexing of coded UCI bits to PUSCH . 115
6.3.2.7 Multiplexing of coded UCI bits with different priority indexes to PUSCH . 115
7 Downlink transport channels and control information . 116
7.1 Broadcast channel. 116
7.1.1 PBCH payload generation . 116
7.1.2 Scrambling . 117
7.1.3 Transport block CRC attachment . 118
7.1.4 Channel coding . 118
7.1.5 Rate matching . 119
7.2 Downlink shared channel and paging channel . 119
7.2.1 Transport block CRC attachment . 119
7.2.2 LDPC base graph selection . 119
7.2.3 Code block segmentation and code block CRC attachment . 119
7.2.4 Channel coding . 119
7.2.5 Rate matching . 120
7.2.6 Code block concatenation . 120
7.3 Downlink control information . 120
7.3.1 DCI formats . 120
7.3.1.0 DCI size alignment . 122
7.3.1.0.1 DCI size alignment for DCI formats for scheduling of sidelink . 125
7.3.1.1 DCI formats for scheduling of PUSCH . 125
7.3.1.1.1 Format 0_0 . 125
7.3.1.1.2 Format 0_1 . 129
7.3.1.1.3 Format 0_2 . 199
7.3.1.1.4 Format 0_3 . 213
7.3.1.2 DCI formats for scheduling of PDSCH . 223
7.3.1.2.1 Format 1_0 . 223
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7.3.1.2.2 Format 1_1 . 227
7.3.1.2.3 Format 1_2 . 254
7.3.1.2.4 Format 1_3 . 259
7.3.1.3 DCI formats for other purposes . 268
7.3.1.3.1 Format 2_0 . 268
7.3.1.3.2 Format 2_1 . 268
7.3.1.3.3 Format 2_2 . 268
7.3.1.3.4 Format 2_3 . 269
7.3.1.3.5 Format 2_4 . 270
7.3.1.3.6 Format 2_5 . 270
7.3.1.3.7 Format 2_6 . 270
7.3.1.3.8 Format 2_7 . 270
7.3.1.3.9 Format 2_8 . 271
7.3.1.3.10 Format 2_9 . 271
7.3.1.4 DCI formats for scheduling of sidelink . 272
7.3.1.4.1 Format 3_0 . 272
7.3.1.4.2 Format 3_1 . 273
7.3.1.4.3 Format 3_2 . 273
7.3.1.5 DCI formats for scheduling of MBS . 274
7.3.1.5.1 Format 4_0 . 274
7.3.1.5.2 Format 4_1 . 274
7.3.1.5.3 Format 4_2 . 275
7.3.2 CRC attachment . 277
7.3.3 Channel coding . 277
7.3.4 Rate matching . 277
8 Sidelink transport channels and control information . 277
8.1 Sidelink broadcast channel . 277
8.1.1 Void . 278
8.2 Sidelink shared channel . 278
8.2.1 Data and control multiplexing . 278
8.3 Sidelink control information on PSCCH . 279
st
8.3.1 1 -stage SCI formats . 279
8.3.1.1 SCI format 1-A . 279
8.3.1.2 SCI format 1-B . 281
8.3.2 CRC attachment . 282
8.3.3 Channel coding . 282
8.3.4 Rate Matching . 282
8.4 Sidelink control information on PSSCH . 282
nd
8.4.1 2 -stage SCI formats . 282
8.4.1.1 SCI format 2-A . 282
8.4.1.2 SCI format 2-B . 283
8.4.1.3 SCI format 2-C . 284
8.4.1.4 SCI format 2-D . 285
8.4.2 CRC attachment . 286
8.4.3 Channel coding . 286
8.4.4 Rate Matching . 286
nd
8.4.5 Multiplexing of coded 2 -stage SCI bits to PSSCH. 287
Annex A (informative): Change history . 288
History . 295

ETSI
3GPP TS 38.212 version 18.8.0 Release 18 6 ETSI TS 138 212 V18.8.0 (2026-02)
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 the third digit is incremented when editorial only changes have been incorporated in the document.
In the present document, modal verbs have the following meanings:
shall indicates a mandatory requirement to do something
shall not indicates an interdiction (prohibition) to do something
The constructions "shall" and "shall not" are confined to the context of normative provisions, and do not appear in
Technical Reports.
The constructions "must" and "must not" are not used as substitutes for "shall" and "shall not". Their use is avoided
insofar as possible, and they are not used in a normative context except in a direct citation from an external, referenced,
non-3GPP document, or so as to maintain continuity of style when extending or modifying the provisions of such a
referenced document.
should indicates a recommendation to do something
should not indicates a recommendation not to do something
may indicates permission to do something
need not indicates permission not to do something
The construction "may not" is ambiguous and is not used in normative elements. The unambiguous constructions
"might not" or "shall not" are used instead, depending upon the meaning intended.
can indicates that something is possible
cannot indicates that something is impossible
The constructions "can" and "cannot" are not substitutes for "may" and "need not".
will indicates that something is certain or expected to happen as a result of action taken by an agency
the behaviour of which is outside the scope of the present document
will not indicates that something is certain or expected not to happen as a result of action taken by an
agency the behaviour of which is outside the scope of the present document
might indicates a likelihood that something will happen as a result of action taken by some agency the
behaviour of which is outside the scope of the present document
ETSI
3GPP TS 38.212 version 18.8.0 Release 18 7 ETSI TS 138 212 V18.8.0 (2026-02)
might not indicates a likelihood that something will not happen as a result of action taken by some agency
the behaviour of which is outside the scope of the present document
In addition:
is (or any other verb in the indicative mood) indicates a statement of fact
is not (or any other negative verb in the indicative mood) indicates a statement of fact
The constructions "is" and "is not" do not indicate requirements.
ETSI
3GPP TS 38.212 version 18.8.0 Release 18 8 ETSI TS 138 212 V18.8.0 (2026-02)
1 Scope
The present document specifies the coding, multiplexing and mapping to physical channels for 5G NR.
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] void.
[3] void.
[4] 3GPP TS 38.211: "NR; Physical channels and modulation".
[5] 3GPP TS 38.213: "NR; Physical layer procedures for control".
[6] 3GPP TS 38.214: "NR; Physical layer procedures for data".
[7] void.
[8] 3GPP TS 38.321: "NR; Medium Access Control (MAC) protocol specification".
[9] 3GPP TS 38.331: "NR; Radio Resource Control (RRC) protocol specification".
[10] 3GPP TS 38.473: "NG-RAN; F1 Application Protocol (F1AP)".
[11] 3GPP TS 36.212: "Evolved Universal Terrestrial Radio Access (E-UTRA); Multiplexing and
channel coding".
[12] 3GPP TS 23.287: "Architecture enhancements for 5G System (5GS) to support
Vehicle-to-Everything (V2X) services".
[13] 3GPP TS 38.101-1: "NR; User Equipment (UE) radio transmission and reception; Part 1: Range 1
Standalone".
[14] 3GPP TS 37.213: "Physical layer procedures for shared spectrum channel access".
3 Definitions of terms, symbols and abbreviations
3.1 Terms
For the purposes of the present document, the terms 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].
3.2 Symbols
Void.
ETSI
3GPP TS 38.212 version 18.8.0 Release 18 9 ETSI TS 138 212 V18.8.0 (2026-02)
3.3 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].
BCH Broadcast Channel
CAPC Channel Access Priority Class
CBG Code Block Group
CBGTI Code Block Group Transmission Information
CG Configured Grant
CG-DFI CG - Downlink Feedback Information
CG-UCI CG - Uplink Control Information
CORESET Control Resource Ret
COT Channel Occupancy Time
CQI Channel Quality Indicator
CRC Cyclic Redundancy Check
CRI CSI-RS Resource Indicator
CSI Channel State Information
CSI-RS CSI - Reference Signal
DAI Downlink Assignment Index
DCI Downlink Control Information
DL Downlink
DL-SCH Downlink - Shared Channel
DMRS Demodulation Reference Signal
HARQ Hybrid Automatic repeat Request
HARQ-ACK Hybrid Automatic repeat Request - Acknowledgement
LDPC Low Density Parity Check
LI Layer Indicator
MBS Multicast Broadcast Services
MCS Modulation and Coding Scheme
NCR Network-controlled repeater
OFDM Orthogonal Frequency Division Multiplex
PBCH Physical Broadcast Channel
PCH Paging Channel
PDCCH Physical Downlink Control Channel
PDSCH Physical Downlink Shared Channel
PMI Precoding Matrix Indicator
PRB Physical Resource Block
PRACH Physical Random Access Channel
PSBCH Physical Sidelink Broadcast Channel
PSCCH Physical Sidelink Control Channel
PSFCH Physical Sidelink Feedback Channel
PSSCH Physical Sidelink Shared Channel
PTRS Phase-Tracking Reference Signal
PUCCH Physical Uplink Control Channel
PUSCH Physical Uplink Shared Channel
RACH Random Access Channel
RI Rank Indicator
RSRP Reference Signal Received Power
SCI Sidelink Control Information
SFCI Sidelink Feedback Control Information
SFN System Frame Number
SL Sidelink
SL-BCH Sidelink - Broadcast Channel
SL PRS Sidelink Positioning Reference Signal
SL-SCH Sidelink - Shared Channel
SR Scheduling Request
SRS Sounding Reference Signal
SS Synchronisation Signal
SUL Supplementary Uplink
ETSI
3GPP TS 38.212 version 18.8.0 Release 18 10 ETSI TS 138 212 V18.8.0 (2026-02)
TCI Transmission Configuration Indicator
TPC Transmit Power Control
TrCH Transport Channel
UCI Uplink Control Information
UE User Equipment
UL Uplink
UL-SCH Uplink Shared Channel
UTO-UCI Unused Transmission Occasion - Uplink Control Information
VRB Virtual Resource Block
ZP CSI-RS Zero power CSI-RS
4 Mapping to physical channels
4.1 Uplink
Table 4.1-1 specifies the mapping of the uplink transport channels to their corresponding physical channels. Table 4.1-2
specifies the mapping of the uplink control channel information to its corresponding physical channel.
Table 4.1-1
TrCH Physical Channel
UL-SCH PUSCH
RACH PRACH
Table 4.1-2
Control information Physical Channel
UCI PUCCH, PUSCH
4.2 Downlink
Table 4.2-1 specifies the mapping of the downlink transport channels to their corresponding physical channels.
Table 4.2-2 specifies the mapping of the downlink control channel information to its corresponding physical channel.
Table 4.2-1
TrCH Physical Channel
DL-SCH PDSCH
BCH PBCH
PCH PDSCH
Table 4.2-2
Control information Physical Channel
DCI PDCCH
4.3 Sidelink
Table 4.3-1 specifies the mapping of the sidelink transport channels to their corresponding physical channels. Table 4.3-
2 specifies the mapping of the sidelink control information and sidelink feedback control information to their
corresponding physical channels.
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Table 4.3-1
TrCH Physical Channel
SL-SCH PSSCH
SL-BCH PSBCH
Table 4.3-2
Control information Physical Channel
st
1 -stage SCI PSCCH
nd
2 -stage SCI PSSCH
SFCI PSFCH
5 General procedures
Data and control streams from/to MAC layer are encoded /decoded to offer transport and control services over the radio
transmission link. Channel coding scheme is a combination of error detection, error correcting, rate matching,
interleaving and transport channel or control information mapping onto/splitting from physical channels.
5.1 CRC calculation
Denote the input bits to the CRC computation by a , a , a , a ,., a , and the parity bits by p , p , p , p ,., p ,
0 1 2 3 A−1 0 1 2 3 L−1
where A is the size of the input sequence and L is the number of parity bits. The parity bits are generated by one of
the following cyclic generator polynomials:
24 23 18 17 14 11 10 7 6 5 4 3
- () for a CRC length
g D = [D + D + D + D + D + D + D + D + D + D + D + D + D +1]
CRC24A
L = 24;
24 23 6 5
- for a CRC length L = 24;
g ()D = [D + D + D + D + D +1]
CRC24B
24 23 21 20 17 15 13 12 8 4 2
for a CRC length ;
- () L = 24
g D = [D + D + D + D + D + D + D + D + D + D + D + D +1]
CRC24C
16 12 5
- for a CRC length ;
g ()D = [D + D + D +1] L = 16
CRC16
11 10 9 5
- for a CRC length L =11;
g ()D = [D + D + D + D +1]
CRC11
6 5
- for a CRC length L = 6 .
g ()D = [D + D +1]
CRC6
The encoding is performed in a systematic form, which means that in GF(2), the polynomial:
A+L−1 A+L−2 L L−1 L−2 1
a D + a D + . + a D + p D + p D + . + p D + p
0 1 A−1 0 1 L−2 L−1
yields a remainder equal to 0 when divided by the corresponding CRC generator polynomial.

The bits after CRC attachment are denoted by b ,b ,b , b ,.,b , where B = A+ L. The relation between and
a b
0 1 2 3 B−1
k k
is:
b = a for
k = 0,1,2,.,A−1
k k
b = p for .
k = A, A+1, A+ 2,.,A+ L −1
k k − A
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3GPP TS 38.212 version 18.8.0 Release 18 12 ETSI TS 138 212 V18.8.0 (2026-02)
5.2 Code block segmentation and code block CRC attachment
5.2.1 Polar coding
The input bit sequence to the code block segmentation is denoted by a , a , a , a ,., a , where A > 0 .
0 1 2 3 A−1
if
I = 1
seg
Number of code blocks: C = 2 ;
else
Number of code blocks:
C =1
end if
;
A'= A/C ⋅C

for i = 0 to
A'− A − 1
a' = 0;
i
end for
for i = A'−A to A'−1
;
a' = a
i i−()A'− A
end for
s = 0 ;
for to
r = 0 C −1
for k = 0 to A'/C −1
;
c = a'
rk s
s = s +1;
end for
The sequence is used to calculate the CRC parity bits according to
c , c , c , c ,., c p , p , p ,., p
r 0 r1 r 2 r()L−1
r 0 r1 r 2 r 3 r()A'/ C−1
Clause 5.1 with a generator polynomial of length L .
for k = A'/C to A'/C + L−1
;
c = p
rk r()k − A'/ C
end for
end for
The value of A is no larger than 1706.
5.2.2 Low density parity check coding
The input bit sequence to the code block segmentation is denoted by b ,b ,b , b ,.,b , where B > 0 . If B is larger
0 1 2 3 B−1
than the maximum code block size , segmentation of the input bit sequence is performed and an additional CRC
K
cb
sequence of L = 24 bits is attached to each code block.
ETSI
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For LDPC base graph 1, the maximum code block size is:
- .
K = 8448
cb
For LDPC base graph 2, the maximum code block size is:
- .
K = 3840
cb
Total number of code blocks C is determined by:
if
B ≤ K
cb
L = 0
Number of code blocks: C =1
′
B = B
else
L = 24
Number of code blocks: C = B /()K − L .
 
cb
B′ = B + C ⋅ L
end if
The bits output from code block segmentation are denoted by c , c , c , c ,., c , where is the code
0 ≤ r < C
...