ETSI TS 101 851-2-3 V3.1.1 (2011-09)

Satellite Earth Stations and Systems (SES); Satellite Component of UMTS/IMT-2000; Part 2: Multiplexing and channel coding; Sub-part 3: G-family enhancements (S-UMTS-G enhanced 25.212)

DTS/SES-00314-2-3

General Information

• Status: Published
• Publication Date: 31-Aug-2011
• Technical Committee: SES MSS - SES WG on Mobile Satellite Systems
• Current Stage: 12 - Completion
• Due Date: 31-Aug-2011
• Completion Date: 01-Sep-2011

Standards Content (Sample)

Technical Specification
Satellite Earth Stations and Systems (SES);
Satellite Component of UMTS/IMT-2000;
Part 2: Multiplexing and channel coding;
Sub-part 3: G-family enhancements
(S-UMTS-G enhanced 25.212)
2 ETSI TS 101 851-2-3 V3.1.1 (2011-09)

Reference
DTS/SES-00314-2-3
Keywords
interface, MES, MSS, radio, satellite, UMTS
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ETSI
3 ETSI TS 101 851-2-3 V3.1.1 (2011-09)
Contents
Intellectual Property Rights . 6
Foreword . 6
Introduction . 6
1 Scope . 8
2 References . 8
2.1 Normative references . 8
2.2 Informative references . 8
3 Definitions, symbols and abbreviations . 9
3.1 Definitions . 9
3.2 Symbols . 10
3.3 Abbreviations . 10
4 Multiplexing, channel coding and interleaving . 11
4.1 General . 11
4.2 General coding/multiplexing of TrCHs . 12
4.2.1 CRC attachment . 16
4.2.1.1 CRC Calculation . 16
4.2.1.2 Relation between input and output of the CRC attachment block . 16
4.2.2 Transport block concatenation and code block segmentation . 17
4.2.2.1 Concatenation of transport blocks . 17
4.2.2.2 Code block segmentation . 17
4.2.3 Channel coding . 18
4.2.3.1 Convolutional coding . 19
4.2.3.2 Turbo coding . 19
4.2.3.2.1 Turbo coder . 19
4.2.3.2.2 Trellis termination for Turbo coder . 20
4.2.3.2.3 Turbo code internal interleaver . 20
4.2.3.3 Concatenation of encoded blocks . 24
4.2.4 Radio frame size equalization . 24
st
4.2.5 1 interleaving . 24
4.2.5.1 Insertion of marked bits in the sequence to be input in first interleaver . 25
st
4.2.5.2 1 interleaver operation . 26
st
4.2.5.3 Relation between input and output of 1 interleaving in uplink . 26
st
4.2.5.4 Relation between input and output of 1 interleaving in downlink . 27
4.2.6 Radio frame segmentation . 27
4.2.6.1 Relation between input and output of the radio frame segmentation block in uplink . 27
4.2.6.2 Relation between input and output of the radio frame segmentation block in downlink . 27
4.2.7 Rate matching . 28
4.2.7.1 Determination of rate matching parameters in uplink . 30
4.2.7.1.1 Determination of SF and number of PhCHs needed . 30
4.2.7.1.2 Determination of parameters needed for calculating the rate matching pattern . 31
4.2.7.1.3 Convolutionally encoded TrCHs . 31
4.2.7.1.4 Turbo encoded TrCHs . 32
4.2.7.2 Determination of rate matching parameters in downlink . 33
4.2.7.2.1 Determination of rate matching parameters for fixed positions of TrCHs . 34
4.2.7.2.2 Determination of rate matching parameters for flexible positions of TrCHs . 37
4.2.7.3 Bit separation and collection in uplink . 39
4.2.7.3.1 Bit separation . 41
4.2.7.3.2 Bit collection . 41
4.2.7.4 Bit separation and collection in downlink . 42
4.2.7.4.1 Bit separation . 43
4.2.7.4.2 Bit collection . 44
4.2.7.5 Rate matching pattern determination . 44
4.2.8 TrCH multiplexing . 45
ETSI
4 ETSI TS 101 851-2-3 V3.1.1 (2011-09)
4.2.9 Insertion of discontinuous transmission (DTX) indication bits . 46
st
4.2.9.1 1 insertion of DTX indication bits . 46
nd
4.2.9.2 2 insertion of DTX indication bits . 46
4.2.10 Physical channel segmentation . 47
4.2.10.1 Relation between input and output of the physical segmentation block in uplink . 48
4.2.10.2 Relation between input and output of the physical segmentation block in downlink . 48
nd
4.2.11 2 interleaving . 48
4.2.12 Physical channel mapping . 49
4.2.12.1 Uplink . 49
4.2.12.2 Downlink . 49
4.2.13 Restrictions on different types of CCTrCHs . 50
4.2.13.1 Uplink Dedicated channel (DCH) . 50
4.2.13.2 Random Access CHannel (RACH) . 50
4.2.13.3 Downlink Dedicated CHannel (DCH) . 51
4.2.13.4 Broadcast channel (BCH) . 51
4.2.13.5 Forward access and paging channels (FACH and PCH) . 51
4.2.14 Multiplexing of different transport channels into one CCTrCH, and mapping of one CCTrCH onto
physical channels . 51
4.2.14.1 Allowed CCTrCH combinations for one UE . 52
4.2.14.1.1 Allowed CCTrCH combinations on the uplink . 52
4.2.14.1.2 Allowed CCTrCH combinations on the downlink . 52
4.2.15 Downlink data randomization . 52
4.3 Transport format detection . 53
4.3.1 Blind transport format detection . 53
4.3.2 Single transport format detection . 54
4.3.3 Transport format detection based on TFCI . 54
4.3.4 Coding of Transport Format Combination Indicator (TFCI) . 54
4.3.5 Mapping of TFCI words . 56
4.3.5.1 Mapping of TFCI word in normal mode . 56
4.3.5.2 Mapping of TFCI word in compressed mode . 56
4.3.5.2.1 Uplink compressed mode . 56
4.3.5.2.2 Downlink compressed mode . 56
4.4 Compressed mode . 57
4.4.1 Frame structure in the uplink . 57
4.4.2 Frame structure types in the downlink . 58
4.4.3 Transmission time reduction method . 58
4.4.3.1 Compressed mode by puncturing . 58
4.4.3.2 Compressed mode by reducing the spreading factor by 2 . 58
4.4.3.3 Compressed mode by higher layer scheduling . 58
4.4.4 Transmission gap position . 59
4.5 TPC command coding . 60
4.5.1 Transmission gap position . 60
4.5.2 Mapping of TPC words . 61
Annex A (informative): Blind transport format detection . 62
A.1 Blind transport format detection using fixed positions . 62
A.1.1 Blind transport format detection using received power ratio. 62
A.1.2 Blind transport format detection using CRC . 62
Annex B (informative): Compressed mode idle lengths . 65
B.1 Idle lengths for DL, UL and DL+UL compressed mode . 65
Annex C (normative): Description of G-family enhancements . 67
C.1 Definition of the optional modes A and C. 67
C.2 Description of Optional mode A . 67
C.3 Description of Optional mode C . 68
Annex D (informative): Change history . 69
ETSI
5 ETSI TS 101 851-2-3 V3.1.1 (2011-09)
D.1 A-family optional features . 69
D.2 C-family optional features . 69
History . 72

ETSI
6 ETSI TS 101 851-2-3 V3.1.1 (2011-09)
Intellectual Property Rights
IPRs essential or potentially essential to the present document may have been declared to ETSI. The information
pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found
in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in
respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web
server (http://ipr.etsi.org).
Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee
can be given as to the existence of other IPRs not referenced in ETSI SR 000 314 (or the updates on the ETSI Web
server) which are, or may be, or may become, essential to the present document.
Foreword
This Technical Specification (TS) has been produced by ETSI Technical Committee Satellite Earth Stations and
Systems (SES).
The present document is specifying the Satellite Radio Interface referenced as SRI Family G at ITU-R, in the frame of
the modification of ITU-R Recommendation M.1457 [i.5]. This modification has been approved at SG8 meeting in
November 2005.
The present document is part 2, sub-part 3 of a multi-part deliverable covering Satellite Earth Stations and Systems
(SES); Satellite Component of UMTS/IMT-2000; G-family enhancements, as identified below:
Part 1: "Physical channels and mapping of transport channels into physical channels";
Part 2: "Multiplexing and channel coding";
Sub-part 1: "G-family (S-UMTS-G 25.212)";
Sub-part 2: "A-family (S-UMTS-A 25.212)";
Sub-part 3: "G-family enhancements (S-UMTS-G enhanced 25.212)";
Part 3: "Spreading and modulation";
Part 4: "Physical layer procedures";
Part 5: "UE Radio Transmission and Reception";
Part 6: "Ground stations and space segment radio transmission and reception".
Introduction
S-UMTS stands for the Satellite component of the Universal Mobile Telecommunication System. S-UMTS systems will
complement the Terrestrial UMTS (T-UMTS) and inter-work with other IMT-2000 family members through the UMTS
rd
core network. S-UMTS will be used to deliver 3 generation Mobile Satellite Services (MSS) utilizing either low
(LEO) or medium (MEO) earth orbiting, or geostationary (GEO) satellite(s). S-UMTS systems are based on terrestrial
3GPP specifications and will support access to GSM/UMTS core networks.
NOTE 1: The term T-UMTS will be used in the present document to further differentiate the Terrestrial UMTS
component.
Due to the differences between terrestrial and satellite channel characteristics, some modifications to the terrestrial
UMTS (T-UMTS) standards are necessary. Some specifications are directly applicable, whereas others are applicable
with modifications. Similarly, some T-UMTS specifications do not apply, whilst some S-UMTS specifications have no
corresponding T-UMTS specification.
ETSI
7 ETSI TS 101 851-2-3 V3.1.1 (2011-09)
Since S-UMTS is derived from T-UMTS, the organization of the S-UMTS specifications closely follows the original
rd
3 Generation Partnership Project (3GPP) structure. The S-UMTS numbers have been designed to correspond to the
3GPP terrestrial UMTS numbering system. All S-UMTS specifications are allocated a unique S-UMTS number as
follows:
S-UMTS-n xx.yyy
Where:
• The numbers xx and yyy correspond to the 3GPP numbering scheme.
• n (n = A, B, C, etc.) denotes the family of S-UMTS specifications.
An S-UMTS system is defined by the combination of a family of S-UMTS specifications and 3GPP specifications, as
follows:
• If an S-UMTS specification exists it takes precedence over the corresponding 3GPP specification (if any). This
precedence rule applies to any references in the corresponding 3GPP specifications.
NOTE 2: Any references to 3GPP specifications within the S-UMTS specifications are not subject to this
precedence rule.
EXAMPLE: An S-UMTS specification may contain specific references to the corresponding 3GPP
specification.
• If an S-UMTS specification does not exist, the corresponding 3GPP specification may or may not apply. The
exact applicability of the complete list of 3GPP specifications shall be defined at a later stage.
The present document is part of the S-UMT sub-part 3 specifications. Sub-part 3 specifications are identified in the title
and can also be identified by the specification number:
• Sub-part 1 specifications have an S-UMTS-G prefix in the title and a sub-part number of "1"
(TS 101 851-x-1).
• Sub-part 2 specifications have an S-UMTS-A prefix in the title and a sub-part number of "2"
(TS 101 851-x-2).
• Sub-part 3 specifications have an S-UMTS-G enhanced prefix in the title and a sub-part number of "3"
(TS 101 851-x-3).
The sub-part 1 specifications introduce the WCDMA satellite radio interface (ITU-R G-family) specifications for the
third generation (3G) wireless communication systems. It is also based on the WCDMA UTRA FDD radio interface
already standardized in 3GPP. Mobile satellite systems intending to use this interface will address user equipment fully
compatible with 3GPP UTRA FDD WCDMA, with adaptation for agility to the Mobile Satellite Service (MSS)
frequency band.
The sub-part 2 specifications introduce the SW-CDMA satellite radio interface (ITU-R A-family) specifications for
third generation (3G) wireless communication systems. SW-CDMA is based on the adaptation to the satellite
environment of terrestrial WCDMA. The intention is to reuse the same core network and reuse the radio interface
specifications for the Is and Cu interface. Only the Uu interface is adapted to the satellite environment. SW-CDMA
operates in FDD mode with RF channel bandwidth of either 2,350 MHz or 4,700 MHz for each transmission direction.
The sub-part 3 specifications introduce the WCDMA satellite radio interface enhancement (G enhance-family). It
considers G-family as radio interface basis, adding as option selected enhancing features from ITU-R A and/or C-family
in order to optimize the radio interface over satellite. It is based on the results of the TR 102 278 [i.6] identifying a way
to achieve harmonization between A, C and G-family satellite radio interfaces for IMT-2000 in ITU-R.
The G-family enhancements made of A, C and G features are described in annex C.
The sub-parts 1 and 2 will be withdrawn if the A and C family will be removed from the satellite radio interface list of
IMT-2000 in ITU-R Recommendation M.1850 [i.7] and then, the sub-part 3 will be revised.
ETSI
8 ETSI TS 101 851-2-3 V3.1.1 (2011-09)
1 Scope
The present document describes the characteristics of the Layer 1 multiplexing and channel coding used for family G
enhanced of the satellite component of UMTS (S-UMTS-G enhanced).
It is based on the FDD mode of UTRA defined by TS 125 211 [i.1], TS 125 212 [i.2], TS 125 213 [i.3] and
TS 125 214 [i.4] and adapted for operation over satellite transponders.
Furthermore, it specifies enhancing features optimizing the basic G family radio interface performances over satellite
and new functions.
2 References
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the
reference document (including any amendments) applies.
Referenced documents which are not found to be publicly available in the expected location might be found at
http://docbox.etsi.org/Reference.
NOTE: While any hyperlinks included in this clause were valid at the time of publication, ETSI cannot guarantee
their long term validity.
2.1 Normative references
The following referenced documents are necessary for the application of the present document.
[1] ETSI TS 101 851-1-3: "Satellite Earth Stations and Systems (SES); Satellite Component of
UMTS/IMT-2000; Part 1: Physical channels and mapping of transport channels into physical
channels; Sub-part 3: G-family enhancements (S-UMTS-G enhanced 25.211)".
[2] ETSI TS 101 851-3-3: "Satellite Earth Stations and Systems (SES); Satellite Component of
UMTS/IMT-2000; Part 3: Spreading and modulation; Sub-part 3: G-family enhancements
(S-UMTS-G enhanced 25.213)".
[3] ETSI TS 101 851-4-3: "Satellite Earth Stations and Systems (SES); Satellite Component of
UMTS/IMT-2000; Part 4: Physical layer procedures; Sub-part 3: G-family enhancements
(S-UMTS-G enhanced 25.214)".
[4] ETSI TS 125 302: "Universal Mobile Telecommunications System (UMTS); Services provided by
the physical layer (3GPP TS 25.302)".
[5] ETSI TS 125 215: "Universal Mobile Telecommunications System (UMTS); Physical layer;
Measurements (FDD) (3GPP TS 25.215)".
2.2 Informative references
The following referenced documents are not necessary for the application of the present document but they assist the
user with regard to a particular subject area.
[i.1] ETSI TS 125 211: "Universal Mobile Telecommunications System (UMTS); Physical channels
and mapping of transport channels onto physical channels (FDD) (3GPP TS 25.211)".
[i.2] ETSI TS 125 212: "Universal Mobile Telecommunications System (UMTS); Multiplexing and
channel coding (FDD) (3GPP TS 25.212)".
[i.3] ETSI TS 125 213: "Universal Mobile Telecommunications System (UMTS); Spreading and
modulation (FDD) (3GPP TS 25.213)".
ETSI
9 ETSI TS 101 851-2-3 V3.1.1 (2011-09)
[i.4] ETSI TS 125 214: "Universal Mobile Telecommunications System (UMTS); Physical layer
procedures (FDD) (3GPP TS 25.214)".
[i.5] ITU-R Recommendation M.1457 (2006): "Detailed specifications of the terrestrial radio interfaces
of International Mobile Telecommunications-2000 (IMT-2000)".
[i.6] ETSI TR 102 278: "Satellite Earth Stations and Systems (SES); Satellite Component of
UMTS/IMT-2000; Considerations on possible harmonization between A, C and G family Satellite
Radio Interface features".
[i.7] ITU-R Recommendation M.1850: "Detailed specifications of the radio interfaces for the satellite
component of International Mobile Telecommunications-2000 (IMT-2000)".
[i.8] ETSI TS 101 851-1-1: "Satellite Earth Stations and Systems (SES); Satellite Component of
UMTS/IMT-2000; Part 1: Physical channels and mapping of transport channels into physical
channels; Sub-part 1: G-family (S-UMTS-G 25.211)".
[i.9] ETSI TS 101 851-1-2: "Satellite Earth Stations and Systems (SES); Satellite Component of
UMTS/IMT-2000; Part 1: Physical channels and mapping of transport channels into physical
channels; Sub-part 2: A-family (S-UMTS-A 25.211)".
[i.10] ETSI TS 101 851-2-1: "Satellite Earth Stations and Systems (SES); Satellite Component of
UMTS/IMT-2000; Part 2: Multiplexing and channel coding; Sub-part 1: G-family
(S-UMTS-G 25.212)".
[i.11] ETSI TS 101 851-2-2: "Satellite Earth Stations and Systems (SES); Satellite Component of
UMTS/IMT-2000; Part 2: Multiplexing and channel coding; Sub-part 2: A-family
(S-UMTS-A 25.212)".
[i.12] ETSI TS 101 851-3-1: "Satellite Earth Stations and Systems (SES); Satellite Component of
UMTS/IMT-2000; Part 3: Spreading and modulation; Sub-part 1: G-family (S-UMTS-G 25.213)".
[i.13] ETSI TS 101 851-3-2: "Satellite Earth Stations and Systems (SES); Satellite Component of
UMTS/IMT-2000; Part 3: Spreading and modulation; Sub-part 2: A-family (S-UMTS-A 25.213)".
[i.14] ETSI TS 101 851-4-1: " Satellite Earth Stations and Systems (SES); Satellite Component of
UMTS/IMT-2000; Part 4: Physical layer procedures; Sub-part 1: G-family (S-UMTS-G 25.214)".
[i.15] ETSI TS 101 851-4-2: "Satellite Earth Stations and Systems (SES); Satellite Component of
UMTS/IMT-2000; Part 4: Physical layer procedures; Sub-part 2: A-family (S-UMTS-A 25.214)".
3 Definitions, symbols and abbreviations
3.1 Definitions
For the purposes of the present document, the following terms and definitions apply:
Transmission Gap (TG): consecutive empty slots that have been obtained with a transmission time reduction method
NOTE: The transmission gap can be contained in one or two consecutive radio frames.
Transmission Gap Length (TGL): number of consecutive empty slots that have been obtained with a transmission
time reduction method 0 ≤ TGL ≤ 14
NOTE: The CFNs of the radio frames containing the first empty slot of the transmission gaps, the CFNs of the
radio frames containing the last empty slot, the respective positions N and N within these frames of
first last
the first and last empty slots of the transmission gaps, and the transmission gap lengths can be calculated
with the compressed mode parameters described in TS 125 215 [5].
ETSI
10 ETSI TS 101 851-2-3 V3.1.1 (2011-09)
TrCH number: transport channel number which identifies a TrCH in the context of L1
NOTE: The L3 transport channel identity (TrCH ID) maps onto the L1 transport channel number. The mapping
between the transport channel number and the TrCH ID is as follows: TrCH 1 corresponds to the TrCH
with the lowest TrCH ID, TrCH 2 corresponds to the TrCH with the next lowest TrCH ID and so on.
3.2 Symbols
For the purposes of the present document, the following symbols apply:
δ DTX indication bits
⎡x⎤ round towards ∞, i.e. integer such that x ≤ ⎡x⎤ < x + 1
⎣x⎦ round towards -∞, i.e. integer such that x - 1 < ⎣x⎦ ≤ x
⎜x⎜ absolute value of x
1; x ≥ 0
⎧
sgn(x) signum function, i.e. sgn(x) =
⎨
−1; x < 0
⎩
N The first slot in the TG, located in the first compressed radio frame if the TG spans two frames
first
N The last slot in the TG, located in the second compressed radio frame if the TG spans two frames
last
N Number of transmitted slots in a radio frame
tr
Unless otherwise is explicitly stated when the symbol is used, the meaning of the following symbols is:
i TrCH number
j TFC number
k Bit number
l TF number
m Transport block number
n Radio frame number of TrCH i
i
p PhCH number
r Code block number
I Number of TrCHs in a CCTrCH
C Number of code blocks in one TTI of TrCH i
i
F Number of radio frames in one TTI of TrCH i
i
M Number of transport blocks in one TTI of TrCH i
i
N Number of data bits that are available for the CCTrCH in a radio frame with TFC j
data,j
cm
N Number of data bits that are available for the CCTrCH in a compressed radio frame with TFC j
data, j
P Number of PhCHs used for one CCTrCH
PL Puncturing Limit for the uplink. Signalled from higher layers
RM Rate Matching attribute for TrCH i. Signalled from higher layers
i
Temporary variables, i.e. variables used in several clauses with different meaning:
x, X
y, Y
z, Z
3.3 Abbreviations
For the purposes of the present document, the following abbreviations apply:
BCH Broadcast CHannel
BER Bit Error Rate
CCPCH Common Control Physical CHannel
CCTrCH Coded Composite Transport CHannel
CFN Connection Frame Number
CRC Cyclic Redundancy Check
DCH Dedicated CHannel
ETSI
11 ETSI TS 101 851-2-3 V3.1.1 (2011-09)
DL DownLink (Forward link)
DPCCH Dedicated Physical Control CHannel
DPCH Dedicated Physical CHannel
DPDCH Dedicated Physical Data CHannel
DTX Discontinuous Transmission
FACH Forward Access CHannel
FBI FeedBack Indicator
FDD Frequency Division Duplex
FDD Frequency Division Duplexing
FER Frame Error Rate
GEO Geostationary Earth Orbit
GF Galois Field
GSM Global Systems for Mobile communications
LEO Low Earth Orbit
LSB Least Significant Bit
MAC Medium Access Control
MEO Medium Earth Orbit
ML Maximum Likelihood
MSB Most Significant Bit
MSS Mobile Satellite Services
PCCC Parallel Concatenated Convolutional Code
PCH Paging CHannel
PhCH Physical CHannel
PL Puncturing Limit
PRACH Physical Random Access CHannel
RACH Random Access CHannel
RF Radio Frequency
RM Rate Matching
S-CCPCH Secondary Common Control Physical CHannel
SF Spreading Factor
SRI Satellite Radio Interface
SSDT Satellite Spot Diversity Transmission
S-UMTS Satellite Universal Mobile Telecommunication Systems
SW-CDMA Satellite Wideband Code Division Multiple Access
TF Transport Format
TFC Transport Format Combination
TFCI Transport Format Combination Indicator
TFCS Transmit Format Combination Set
TG Transmission Gap
TGL Transmission Gap Length
TPC Transmit Power Control
TrCH Transport CHannel
TTI Transmission Time Interval
T-UMTS Terrestrial Universal Mobile Telecommunications System
UL UpLink (Reverse link)
USRAN UMTS Satellite Radio Access Network
UTRA UMTS Terrestrial Radio Access
UTRA UMTS Terrestrial Radio Access
WCDMA Wideband Code Division Multiple Access
4 Multiplexing, channel coding and interleaving
4.1 General
Data stream from/to MAC and higher layers (Transport block/Transport block set) is encoded/decoded to offer transport
services over the radio transmission link. Channel coding scheme is a combination of error detection, error correcting,
rate matching, interleaving and transport channels mapping onto/splitting from physical channels.
ETSI
12 ETSI TS 101 851-2-3 V3.1.1 (2011-09)
4.2 General coding/multiplexing of TrCHs
This clause only applies to the transport channels:
• DCH;
• RACH;
• BCH;
• FACH; and
• PCH.
Other transport channels which do not use the general method are described separately below.
Data arrives to the coding/multiplexing unit in form of transport block sets once every transmission time interval. The
transmission time interval is transport-channel specific from the set {10 ms, 20 ms, 40 ms, 80 ms}.
The following coding/multiplexing steps can be identified:
- add CRC to each transport block (see clause 4.2.1);
- transport block concatenation and code block segmentation (see clause 4.2.2);
- channel coding (see clause 4.2.3);
- radio frame equalization (see clause 4.2.4);
- rate matching (see clause 4.2.7);
- insertion of discontinuous transmission (DTX) indication bits (see clause 4.2.9);
- interleaving (two steps, see clauses 4.2.5 and 4.2.11);
- radio frame segmentation (see clause 4.2.6);
- multiplexing of transport channels (see clause 4.2.8);
- physical channel segmentation (see clause 4.2.10);
- mapping to physical channels (see clause 4.2.12);
- data scrambling (only for downlink, and optional) (see clause 4.2.15).
The coding/multiplexing steps for uplink and downlink are shown in figures 1 and 2 respectively (N.B. figure 1 and 2a
applies for optional mode A).
ETSI
PhCH#2
PhCH#1
13 ETSI TS 101 851-2-3 V3.1.1 (2011-09)

a ,a ,a ,K,a
im1 im2 im3 imA
i
CRC attachment
b ,b ,b ,K,b
im1 im2 im3 imB
i
TrBk concatenation /
Code block segmentation
o ,o ,o ,K,o
ir1 ir2 ir3 irK
i
Channel coding
c ,c ,c ,K,c
i1 i2 i3 iE
i
Radio frame equalisation
t ,t ,t ,K,t
i1 i2 i3 iT
i
st
1 interleaving
d ,d ,d ,K,d
i1 i2 i3 iT
i
Radio frame segmentation
e ,e ,e ,K,e
i1 i2 i3 iN
i
Rate
Rate matching
matching
f , f , f ,K, f
i1 i2 i3 iV
i
TrCH Multiplexing
s ,s ,s ,K,s
CCTrCH
1 2 3 S
Physical channel
segmentation
u ,u ,u ,K,u
p1 p2 p3 pU
nd
2 interleaving
v ,v ,v ,K,v
p1 p2 p3 pU
Physical channel mapping
Figure 1: Transport channel multiplexing structure for uplink
ETSI
PhCH#2
PhCH#1
14 ETSI TS 101 851-2-3 V3.1.1 (2011-09)

a ,a ,a ,K,a
im1 im2 im3 imA
i
CRC attachment
b ,b ,b ,K,b
im1 im2 im3 imB
i
TrBk concatenation /
Code block segmentation
o ,o ,o ,K,o
ir1 ir 2 ir3 irK
i
Channel coding
c ,c ,c ,K,c
i1 i2 i3 iE
i
Rate
Rate matching
matching
g , g , g ,K, g
i1 i2 i3 iG
i
st
1 insertion of DTX
indication
h , h , h ,K , h
i1 i 2 i3 iD
i
st
1 interleaving
q ,q ,q ,K,q
i1 i2 i3 iQ
i
Radio frame segmentation
f , f , f ,K, f
i1 i2 i3 iV
i
TrCH Multiplexing
s ,s ,s ,K,s
1 2 3 S
nd
2 insertion of DTX
indication
w , w , w ,K, w
1 2 3 R
CCTrCH
Physical channel
segmentation
u ,u ,u ,K,u
p1 p2 p3 pU
nd
2 interleaving
v ,v ,v ,K,v
p1 p2 p3 pU
Physical channel mapping
Figure 2: Transport channel multiplexing structure for downlink
The single output data stream from the TrCH multiplexing, including DTX indication bits in downlink, is denoted
Coded Composite Transport CHannel (CCTrCH). A CCTrCH can be mapped to one or several physical channels.
ETSI
PhCH#2
PhCH#1
15 ETSI TS 101 851-2-3 V3.1.1 (2011-09)
In optional mode A, the following is applied with the addition of add a scrambling step (in bold in the figure) for
downlink:
a ,a ,a ,K,a
im1 im2 im3 imA
i
CRC attachment
b ,b ,b ,K,b
im1 im2 im3 imB
i
TrBk concatenation /
Code block segmentation
o ,o ,o ,K,o
ir1 ir 2 ir3 irK
i
Channel coding
c ,c ,c ,K,c
i1 i2 i3 iE
i
Rate
Rate matching
matching
g , g , g ,K, g
i1 i2 i3 iG
i
Insertion of DTX indication
with fixed positions
h , h ,h ,K,h
i1 i2 i3 i(F H )
i i
st
1 interleaving
q ,q ,q ,K,q
i1 i2 i3 iQ
i
Radio frame segmentation
f , f , f ,K, f
i1 i2 i3 iV
i
TrCH Multiplexing
s ,s ,s ,K,s
1 2 3 S
Insertion of DTX indication
with flexible positions
w ,w ,w ,K,w
1 2 3 PU
Physical channel
segmentation
u ,u ,u ,K,u
p1 p2 p3 pU
nd
2 interleaving
u ,u ,u ,K,u
p1 p2 p3 pU
Scrambling
v ,v ,v ,K,v
p1 p2 p3 pU
Physical channel mapping
Figure 2a: Transport channel multiplexing structure for downlink (Optional mode A)
ETSI
16 ETSI TS 101 851-2-3 V3.1.1 (2011-09)
4.2.1 CRC attachment
Error detection is provided on transport blocks through a Cyclic Redundancy Check (CRC). The size of the CRC is
24 bits, 16 bits, 12 bits, 8 bits or 0 bit and it is signalled from higher layers what CRC size that should be used for each
TrCH.
4.2.1.1 CRC Calculation
The entire transport block is used to calculate the CRC parity bits for each transport block. The parity bits are generated
by one of the following cyclic generator polynomials:
24 23 6 5
- g (D) = D + D + D + D + D + 1;
CRC24
16 12 5
- g (D) = D + D + D + 1;
CRC16
12 11 3 2
- g (D) = D + D + D + D + D + 1;
CRC12
8 7 4 3
- g (D) = D + D + D + D + D + 1.
CRC8
Denote the bits in a transport block delivered to layer 1 by a , a , a ,K, a , and the parity bits by
im1 im2 im3 imA
i
. A is the size of a transport block of TrCH i, m is the transport block number, and L is the
p , p , p ,K , p
i i
im 1 im 2 im 3 imL
i
number of parity bits. L can take the values 24, 16, 12, 8, or 0 depending on what is signalled from higher layers.
i
The encoding is performed in a systematic form, which means that in GF(2), the polynomial:
A +23 A [phone]
i i
a D + a D +K+ a D + p D + p D +K+ p D + p
im1 im2 imA im1 im2 im23 im24
i
yields a remainder equal to 0 when divided by g (D), polynomial:
CRC24
A +15 A [phone]
i i
a D + a D +K + a D + p D + p D +K + p D + p
im1 im2 imA im1 im2 im15 im16
i
yields a remainder equal to 0 when divided by g (D), polynomial:
CRC16
A +11 A [phone]
i i
a D + a D +K + a D + p D + p D +K + p D + p
im1 im2 imA im1 im2 im11 im12
i
yields a remainder equal to 0 when divided by g (D) and polynomial:
CRC12
A +7 A +6 8 7 6 1
i i
a D + a D +K + a D + p D + p D +K + p D + p
im1 im2 imA im1 im2 im7 im8
i
yields a remainder equal to 0 when divided by g (D).
CRC8
If no transport blocks are input to the CRC calculation (M = 0), no CRC attachment shall be done. If transport blocks
i
are input to the CRC calculation (M ≠ 0) and the size of a transport block is zero (A = 0), CRC shall be attached, i.e. all
i i
parity bits equal to zero.
4.2.1.2 Relation between input and output of the CRC attachment block
The bits after CRC attachment are denoted by b ,b ,b ,K,b , where B = A + L . The relation between a
im1 im2 im3 imB i i i imk
i
and b is:
imk
b = a k = 1, 2, 3, …, A
imk imk i
b = p k = A + 1, A + 2, A + 3, …, A + L .
imk im(L +1−(k − A )) i i i i i
i i
ETSI
17 ETSI TS 101 851-2-3 V3.1.1 (2011-09)
4.2.2 Transport block concatenation and code block segmentation
All transport blocks in a TTI are serially concatenated. If the number of bits in a TTI is larger than Z, the maximum size
of a code block in question, then code block segmentation is performed after the concatenation of the transport blocks.
The maximum size of the code blocks depends on whether convolutional coding or turbo coding is used for the TrCH.
4.2.2.1 Concatenation of transport blocks
The bits input to the transport block concatenation are denoted by b ,b ,b ,K,b where i is the TrCH
im1 im2 im3 imB
i
number, m is the transport block number, and B is the number of bits in each block (including CRC). The number of
i
transport blocks on TrCH i is denoted by M . The bits after concatenation are denoted by x , x , x ,K, x , where i
i i1 i2 i3 iX
i
is the TrCH number and X = M B . They are defined by the following relations:
i i i
x = b k = 1, 2, …, B
ik i1k i
x = b k = B + 1, B + 2, …, 2B
ik i,2,(k −B ) i i i
i
x = b k = 2B + 1, 2B + 2, …, 3B
ik i,3,(k −2B ) i i i
i
K
x = b k = (M - 1)B + 1, (M - 1)B + 2, …, M B .
ik i,M ,(k −(M −1)B ) i i i i i i
i i i
4.2.2.2 Code block segmentation
Segmentation of the bit sequence from transport block concatenation is performed if X > Z. The code blocks after
i
segmentation are of the same size. The number of code blocks on TrCH i is denoted by C . If the number of bits input to
i
the segmentation, X , is not a multiple of C , filler bits are added to the beginning of the first block. If turbo coding is
i i
selected and X < 40,
...