SIST EN 300 909 V6.1.3:2003
(Main)Digital cellular telecommunications system (Phase 2+) (GSM); Channel coding (GSM 05.03 version 6.1.2 Release 1997)
Digital cellular telecommunications system (Phase 2+) (GSM); Channel coding (GSM 05.03 version 6.1.2 Release 1997)
SUBJECT TS Change of Status to EN
Digitalni celični telekomunikacijski sistem (faza 2+) – Kodiranje kanalov (GSM 05.03, različica 6.1.3, izdaja 1997)
General Information
Standards Content (Sample)
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Digital cellular telecommunications system (Phase 2+) (GSM); Channel coding (GSM 05.03 version 6.1.2 Release 1997)33.070.50Globalni sistem za mobilno telekomunikacijo (GSM)Global System for Mobile Communication (GSM)ICS:Ta slovenski standard je istoveten z:EN 300 909 Version 6.1.3SIST EN 300 909 V6.1.3:2003en01-december-2003SIST EN 300 909 V6.1.3:2003SLOVENSKI
STANDARD
EN 300 909 V6.1.3 (1999-03)European Standard (Telecommunications series)Digital cellular telecommunications system (Phase 2+);Channel coding(GSM 05.03 version 6.1.3 Release 1997)GLOBAL SYSTEM
FOR MOBILE COMMUNICATIONSRSIST EN 300 909 V6.1.3:2003
ETSIEN 300 909 V6.1.3 (1999-03)2GSM 05.03 version 6.1.3 Release 1997ReferenceDEN/SMG-020503Q6 (8f0030e0.PDF)KeywordsDigital cellular telecommunications system,Global System for Mobile communications (GSM)ETSIPostal addressF-06921 Sophia Antipolis Cedex - FRANCEOffice address650 Route des Lucioles - Sophia AntipolisValbonne - FRANCETel.: +33 4 92 94 42 00
Fax: +33 4 93 65 47 16Siret N° 348 623 562 00017 - NAF 742 CAssociation à but non lucratif enregistrée à laSous-Préfecture de Grasse (06) N° 7803/88Internetsecretariat@etsi.frIndividual copies of this ETSI deliverablecan be downloaded fromhttp://www.etsi.orgIf you find errors in the present document, send yourcomment to: editor@etsi.frCopyright NotificationNo part may be reproduced except as authorized by written permission.The copyright and the foregoing restriction extend to reproduction in all media.© European Telecommunications Standards Institute 1999.All rights reserved.SIST EN 300 909 V6.1.3:2003
ETSIEN 300 909 V6.1.3 (1999-03)3GSM 05.03 version 6.1.3 Release 1997ContentsIntellectual Property Rights.6Foreword.61Scope.71.1Normative references.71.2Abbreviations.72General.82.1General organization.82.2Naming Convention.103Traffic Channels (TCH).103.1Speech channel at full rate (TCH/FS and TCH/EFS).113.1.1Preliminary channel coding for EFR only.113.1.1.1CRC calculation.113.1.1.2Repetition bits.113.1.1.3Correspondence between input and output of preliminary channel coding.123.1.2Channel coding for FR and EFR.123.1.2.1Parity and tailing for a speech frame.123.1.2.2Convolutional encoder.133.1.3Interleaving.133.1.4Mapping on a Burst.133.2Speech channel at half rate (TCH/HS).133.2.1Parity and tailing for a speech frame.143.2.2Convolutional encoder.143.2.3Interleaving.153.2.4Mapping on a burst.153.3Data channel at full rate, 12.0 kbit/s radio interface rate (9.6 kbit/s services (TCH/F9.6)).153.3.1Interface with user unit.153.3.2Block code.163.3.3Convolutional encoder.163.3.4Interleaving.163.3.5Mapping on a Burst.163.4Data channel at full rate, 6.0 kbit/s radio interface rate (4.8 kbit/s services (TCH/F4.8)).163.4.1Interface with user unit.173.4.2Block code.173.4.3Convolutional encoder.173.4.4Interleaving.173.4.5Mapping on a Burst.173.5Data channel at half rate, 6.0 kbit/s radio interface rate (4.8 kbit/s services (TCH/H4.8)).173.5.1Interface with user unit.183.5.2Block code.183.5.3Convolutional encoder.183.5.4Interleaving.183.5.5Mapping on a Burst.183.6Data channel at full rate, 3.6 kbit/s radio interface rate (2.4 kbit/s and less services (TCH/F2.4)).183.6.1Interface with user unit.183.6.2Block code.183.6.3Convolutional encoder.183.6.4Interleaving.193.6.5Mapping on a Burst.193.7Data channel at half rate, 3.6 kbit/s radio interface rate (2.4 kbit/s and less services (TCH/H2.4)).193.7.1Interface with user unit.193.7.2Block code.193.7.3Convolutional encoder.193.7.4Interleaving.193.7.5Mapping on a Burst.19SIST EN 300 909 V6.1.3:2003
ETSIEN 300 909 V6.1.3 (1999-03)4GSM 05.03 version 6.1.3 Release 19973.8Data channel at full rate, 14.5 kbit/s radio interface rate (14.4 kbit/s services (TCH/F14.4)).203.8.1Interface with user unit.203.8.2Block code.203.8.3Convolutional encoder.203.8.4Interleaving.203.8.5Mapping on a Burst.204Control Channels.214.1Slow associated control channel (SACCH).214.1.1Block constitution.214.1.2Block code.214.1.3Convolutional encoder.214.1.4Interleaving.224.1.5Mapping on a Burst.224.2Fast associated control channel at full rate (FACCH/F).224.2.1Block constitution.224.2.2Block code.224.2.3Convolutional encoder.224.2.4Interleaving.224.2.5Mapping on a Burst.224.3Fast associated control channel at half rate (FACCH/H).234.3.1Block constitution.234.3.2Block code.234.3.3Convolutional encoder.234.3.4Interleaving.234.3.5Mapping on a Burst.244.4Broadcast control, Paging, Access grant, Notification and Cell broadcast channels (BCCH, PCH,AGCH, NCH, CBCH).244.5Stand-alone dedicated control channel (SDCCH).244.6Random access channel (RACH).254.7Synchronization channel (SCH).254.8Access Burst on circuit switched channels other than RACH.264.9Access Bursts for uplink access on a channel used for VGCS.265Packet Switched Channels.265.1Packet data traffic channel (PDTCH).265.1.1Packet data block type 1 (CS-1).265.1.2Packet data block type 2 (CS-2).265.1.2.1Block constitution.265.1.2.2Block code.265.1.2.3Convolutional encoder.275.1.2.4Interleaving.275.1.2.5Mapping on a burst.275.1.3Packet data block type 3 (CS-3).285.1.3.1Block constitution.285.1.3.2Block code.285.1.3.3Convolutional encoder.285.1.3.4Interleaving.295.1.3.5Mapping on a burst.295.1.4Packet data block type 4 (CS-4).295.1.4.1Block constitution.295.1.4.2Block code.295.1.4.3Convolutional encoder.295.1.4.4Interleaving.305.1.4.5Mapping on a burst.305.2Packet control channels (PACCH, PBCCH, PAGCH, PPCH, PNCH, PTCCH).305.3Packet random access channel (PRACH).305.3.1Packet Access Burst.305.3.2Extended Packet Access Burst.305.4Access Burst on packet switched channels other than PRACH.31SIST EN 300 909 V6.1.3:2003
ETSIEN 300 909 V6.1.3 (1999-03)5GSM 05.03 version 6.1.3 Release 1997Annex A (informative):Summary of Channel Types.43Annex B (informative):Summary of Polynomials Used for Convolutional Codes.44Annex C (informative):Change control history.45History.46SIST EN 300 909 V6.1.3:2003
ETSIEN 300 909 V6.1.3 (1999-03)6GSM 05.03 version 6.1.3 Release 1997Intellectual Property RightsIPRs essential or potentially essential to the present document may have been declared to ETSI. The informationpertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be foundin SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in respectof ETSI standards", which is available free of charge from the ETSI Secretariat. Latest updates are available on theETSI Web server (http://www.etsi.org/ipr).Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guaranteecan be given as to the existence of other IPRs not referenced in SR 000 314 (or the updates on the ETSI Web server)which are, or may be, or may become, essential to the present document.ForewordThis European Standard (Telecommunications series) has been produced by ETSI Special Mobile Group (SMG).This EN specifies the data blocks given to the encryption unit. It includes the specification of encoding, reordering,interleaving and the stealing flag within the digital cellular telecommunications system (Phase 2+).The contents of this EN are subject to continuing work within SMG and may change following formal SMG approval.Should SMG modify the contents of this EN it will then be republished by ETSI with an identifying change of releasedate and an increase in version number as follows:Version 6.x.ywhere:6indicates release 1997 of GSM Phase 2+xthe second digit is incremented for changes of substance, i.e. technical enhancements, corrections, updates,etcythe third digit is incremented when editorial only changes have been incorporated in the specification.National transposition datesDate of adoption of this EN:12 March 1999Date of latest announcement of this EN (doa):30 June 1999Date of latest publication of new National Standardor endorsement of this EN (dop/e):31 December 1999Date of withdrawal of any conflicting National Standard (dow):31 December 1999SIST EN 300 909 V6.1.3:2003
ETSIEN 300 909 V6.1.3 (1999-03)7GSM 05.03 version 6.1.3 Release 19971ScopeA reference configuration of the transmission chain is shown in GSM 05.01 [4]. According to this referenceconfiguration, this EN specifies the data blocks given to the encryption unit.It includes the specification of encoding, reordering, interleaving and the stealing flag. It does not specify the channeldecoding method.The definition is given for each kind of logical channel, starting from the data provided to the channel encoder by thespeech coder, the data terminal equipment, or the controller of the Mobile Station (MS) or Base Transceiver Station(BTS). The definitions of the logical channel types used in this technical specification are given in GSM 05.02 [5], asummary is in annex A.1.1Normative referencesThe following documents contain provisions which, through reference in this text, constitute provisions of the presentdocument.-References are either specific (identified by date of publication, edition number, version number, etc.) ornon-specific.-For a specific reference, subsequent revisions do not apply.-For a non-specific reference, the latest version applies.-A non-specific reference to an ETS shall also be taken to refer to later versions published as an EN with the samenumber.[1]GSM 01.04: "Digital cellular telecommunications system (Phase 2+); Abbreviations andacronyms".[2]GSM 04.08: "Digital cellular telecommunications system (Phase 2+); Mobile radio interface layer3 specification".[3]GSM 04.21: "Digital cellular telecommunications system (Phase 2+); Rate adaption on the MobileStation - Base Station System (MS - BSS) interface".[4]GSM 05.01: "Digital cellular telecommunications system (Phase 2+); Physical layer on the radiopath General description".[5]GSM 05.02: "Digital cellular telecommunications system (Phase 2+); Multiplexing and multipleaccess on the radio path".[6]GSM 05.05: "Digital cellular telecommunications system (Phase 2+); Radio Transmission andReception".[7]GSM 06.10: "Digital cellular telecommunications system; Full rate speech transcoding".[8]GSM 06.20: "Digital cellular telecommunications system; Half rate speech transcoding".[9]GSM 06.60: "Digital cellular telecommunications system; Enhanced Full Rate (EFR) speechtranscoding".[10]GSM 03.64: "Digital cellular telecommunications system (Phase 2+); General Packet RadioService (GPRS); Overall description of the GPRS Radio Interface; Stage 2".1.2AbbreviationsAbbreviations used in this EN are listed in GSM 01.04.SIST EN 300 909 V6.1.3:2003
ETSIEN 300 909 V6.1.3 (1999-03)8GSM 05.03 version 6.1.3 Release 19972General2.1General organizationEach channel has its own coding and interleaving scheme. However, the channel coding and interleaving is organized insuch a way as to allow, as much as possible, a unified decoder structure.Each channel uses the following sequence and order of operations:-The information bits are coded with a systematic block code, building words of information + parity bits.-These information + parity bits are encoded with a convolutional code, building the coded bits.-Reordering and interleaving the coded bits, and adding a stealing flag, gives the interleaved bits.All these operations are made block by block, the size of which depends on the channel. However, most of the channelsuse a block of 456 coded bits which is interleaved and mapped onto bursts in a very similar way for all of them. Figure 1gives a diagram showing the general structure of the channel coding.This block of 456 coded bits is the basic structure of the channel coding scheme. In the case of full rate speech TCH,this block carries the information of one speech frame. In case of control channels, it carries one message.In the case of half rate speech TCH, the information of one speech frame is carried in a block of 228 coded bits.In the case of the Enhanced full rate speech the information bits coming out of the source codec first go though apreliminary channel coding. then the channel coding as described above takes place.In the case of a packet switched channel the block of 456 coded bits carries one radio block.In the case of FACCH, a coded message block of 456 bits is divided into eight sub-blocks. The first four sub-blocks aresent by stealing the even numbered bits of four timeslots in consecutive frames used for the TCH. The other foursub-blocks are sent by stealing the odd numbered bits of the relevant timeslot in four consecutive used frames delayed 2or 4 frames relative to the first frame. Along with each block of 456 coded bits there is, in addition, a stealing flag (8bits), indicating whether the block belongs to the TCH or to the FACCH. In the case of SACCH, BCCH or CCCH, thisstealing flag is dummy. In the case of a packet switched channel, these bits are used to indicate the coding scheme used.Some cases do not fit in the general organization, and use short blocks of coded bits which are sent completely in onetimeslot. They are the random access messages of-the RACH-or PRACHon uplink and the synchronization information broadcast of the SCH on downlink.SIST EN 300 909 V6.1.3:2003
ETSIEN 300 909 V6.1.3 (1999-03)9GSM 05.03 version 6.1.3 Release 1997speech frame112 bits3.2speech frame260 bits3.1message184 bits4.1.1data frameN0 bits3.n.1messageP0 bits4.6, 4.7, 5.3.2RLC blockQ0 bits5.1.n.1speech frame244 bits3.1interface1interface2TCH/HS(half ratespeech TCH)TCH/FS(full ratespeech TCH)SACCH, FACCH,BCCH, CBCH, PCHAGCH, SDCCHdata TCHsPRACHRACH,SCHcyclic code+ tailin: 260 bitsout: 267 bits3.1.1cyclic code+ tailin: 112 bitsout: 121 bits3.2.1Fire code+tailin: 184 bitsout: 228 bits4.1.2+tailin: N0 bitsout: N1 bits3.n.2cyclic code+ tailin: P0 bitsout: P1 bits4.6, 4.7, 5.3.2cyclic code+ tailin: Q0 bitsout: Q1 bits5.1.n.2cyclic code+ repetitionin: 244 bitsout: 260 bits3.1.1interface3interface4TCH/F2.4othersTCH/FS, TCH/EFSTCH/F2.4, FACCHothersencryption unitdiagonal interleaving+ stealing flagsin: 456 bitsout: 4 blocksdiagonally interleavedto depth 19, startingon consecutive bursts3.n.4reordering and partitioning+stealing flagin: 456 bitsout: 8 blocks3.1.3, 4.1.4, 4.3.4block rectangularinterleavingin: 8 blocksout: pairs ofblocks4.1.4block diagonalinterleavingin: 8 blocksout: pairs ofblocks3.1.3, 4.3.4reordering and partitioning+stealing flagin: 228 bitsout: 4 blocks3.2.3block diagonalinterleavingin: 4 blocksout: pairs ofblocks3.2.3convolutionalcodek=7, 2 classesin: 121 bitsout: 228 bits3.2.2convolutionalcodek=5, 2 classesin: 267 bitsout: 456 bits3.1.2convolutionalcodek=5, rate 1/2in: 228 bitsout: 456 bits4.1.3convolutionalcodek=5, rate rin: N1 bitsout: 456 bits3.n.3convolutionalcodek=5, rate rin: P1 bitsout: P2 bits4.6, 4.7, 5.3.2convolutionalcodek=5, rate rin: Q1 bitsout: 456 bits5.1.n.3PDTCH, PACCH,PBCCH, PAGCH, PPCH, PNCH, PTCCH/Dreordering and partitioning+code identifierin: 456 bitsout: 8 blocks4.1.4interface0TCH/EFS(Enhanced full ratespeech TCH)CS-1othersCS-4othersPTCCH/UFigure 1: Channel Coding and Interleaving OrganizationIn each box, the last line indicates the chapter defining the function. In the case of RACH, P0 = 8 and P1 = 18; inthe case of SCH, P0 = 25 and P1 = 39. In the case of data TCHs, N0, N1 and n depend on the type of data TCH.Interfaces:1)information bits (d);2)information + parity + tail bits (u);3)coded bits (c);4)interleaved bits (e).SIST EN 300 909 V6.1.3:2003
ETSIEN 300 909 V6.1.3 (1999-03)10GSM 05.03 version 6.1.3 Release 19972.2Naming ConventionFor ease of understanding a naming convention for bits is given for use throughout the technical specification:-General naming:"k" and "j" for numbering of bits in data blocks and bursts;"Kx" gives the amount of bits in one block, where "x" refers to the data type;"n" is used for numbering of delivered data blocks where;"N" marks a certain data block;"B" is used for numbering of bursts or blocks where;"B0" marks the first burst or block carrying bits from the data block with n = 0 (first data block in thetransmission).-Data delivered to the preliminary channel encoding unit (for EFR only):s(k) for k = 1., Ks-Data delivered by the preliminary channel encoding unit (for EFR only) before bits rearrangementw(k) for k = 1., Kw-Data delivered to the encoding unit (interface 1 in figure 1):d(k)fork = 0,1,.,Kd-1-Code identifying the used coding scheme (for packet switched channels only):q(k)for k = 0,1,., 7-Data after the first encoding step (block code, cyclic code; interface 2 in figure 1):u(k)fork = 0,1,.,Ku-1-Data after the second encoding step (convolutional code ; interface 3 in figure 1):c(n,k) or c(k)fork = 0,1,.,Kc-1n = 0,1,.,N,N+1,.-Interleaved data:i(B,k)fork = 0,1,.,Ki-1B = B0, B0+1,.-Bits in one burst (interface 4 in figure 1):e(B,k)for k = 0,1,114,115B = B0,B0+1,.3Traffic Channels (TCH)Two kinds of traffic channel are considered: speech and data. Both of them use the same general structure (see figure 1),and in both cases, a piece of information can be stolen by the FACCH.SIST EN 300 909 V6.1.3:2003
ETSIEN 300 909 V6.1.3 (1999-03)11GSM 05.03 version 6.1.3 Release 19973.1Speech channel at full rate (TCH/FS and TCH/EFS)The speech coder (whether Full rate or Enhanced full rate) delivers to the channel encoder a sequence of blocks of data.In case of a full rate and enhanced full rate speech TCH, one block of data corresponds to one speech frame.For the full rate coder each block contains 260 information bits, including 182 bits of class 1 (protected bits), and 78 bitsof class 2 (no protection), (see table 2).The bits delivered by the speech coder are received in the order indicated in GSM 06.10 and have to be rearrangedaccording to table 2 before channel coding as defined in subclauses 3.1.1 to 3.1.4. The rearranged bits are labelled{d(0),d(1),.,d(259)}, defined in the order of decreasing importance.For the EFR coder each block contains 244 information bits. The block of 244 information bits, labelled s(1)., s(244),passes through a preliminary stage, applied only to EFR (see figure 1) which produces 260 bits corresponding to the244 input bits and 16 redundancy bits. Those 16 redundancy bits correspond to 8 CRC bits and 8 repetition bits, asdescribed in subclause 3.1.1. The 260 bits, labelled w(1).w(260), have to be rearranged according to table 7 before theyare delivered to the channel encoding unit which is identical to that of the TCH/FS. The 260 bits block includes 182 bitsof class 1(protected bits) and 78 bits of class 2 (no protection). The class 1 bits are further divided into the class 1a andclass 1b, class 1a bits being protected by a cyclic code and the convolutional code whereas the class 1b are protected bythe convolutional code only.3.1.1Preliminary channel coding for EFR only3.1.1.1CRC calculationAn 8-bit CRC is used for error-detection. These 8 parity bits (bits w253-w260) are generated by the cyclic generatorpolynomial: g(D) = D8 + D4 + D3 + D2 + 1 from the 65 most important bits (50 bits of class 1a and 15 bits of class 1b).These 65 bits (b(1)-b(65)) are taken from the table 5 in the following order (read row by row, left to right):s39s40s41s42s43s44s48s87s45s2s3s8s10s18s19s24s46s47s142s143s144s145s146s147s92s93s195s196s98s137s148s94s197s149s150s95s198s4s5s11s12s16s9s6s7s13s17s20s96s199s1s14s15s21s25s26s28s151s201s190s240s88s138s191s241The encoding is performed in a systematic form, which means that, in GF(2), the polynomial:b(1)D72 + b(2)D71 +.+b(65)D8 + p(1)D7 + p(2)D6 +.+ p(7)D1 + p(8)p(1) - p(8): the parity bits (w253-w260)b(1) - b(65) = the data bits from the table abovewhen divided by g(D), yields a remainder equal to 0.3.1.1.2Repetition bitsThe repeated bits are s70, s120, s173 and s223. They correspond to one of the bits in each of the PULSE_5, the mostsignificant one not protected by the channel coding stage.SIST EN 300 909 V6.1.3:2003
ETSIEN 300 909 V6.1.3 (1999-03)12GSM 05.03 version 6.1.3 Release 19973.1.1.3Correspondence between input and output of preliminary channel codingThe preliminary coded bits w(k) for k = 1 to 260 are hence defined by:w(k) = s(k) for k = 1 to 71w(k) = s(k-2) for k = 74 to 123w(k) = s(k-4) for k = 126 to 178w(k) = s(k-6) for k = 181 to s230w(k) = s(k-8) for k = 233 to s252Repetition bits:w(k) = s(70)for k = 72 and 73w(k) = s(120) for k = 124 and 125w(k) = s(173) for k = 179 and 180w(k) = s(223) for k = 231 and 232Parity bits:w(k = p(k-252) for k = 253 to 2603.1.2Channel coding for FR and EFR3.1.2.1Parity and tailing for a speech framea)Parity bits:The first 50 bits of class 1 (known as class 1a for the EFR) are protected by three parity bits used for errordetection. These parity bits are added to the 50 bits, according to a degenerate (shortened) cyclic code (53,50,2),using the generator polynomial:g(D) = D3 + D + 1The encoding of the cyclic code is performed in a systematic form, which means that, in GF(2), the polynomial:d(0)D52 + d(1)D51 +. + d(49)D3 + p(0)D2 + p(1)D+ p(2)where p(0), p(1), p(2) are the parity bits, when divided by g(D), yields a remainder equal to:1 + D + D2b)Tailing bits and reordering:The information and parity bits of class 1 are reordered, defining 189 information + parity + tail bits of class 1,{u(0),u(1),.,u(188)} defined by:u(k)= d(2k)andu(184-k) = d(2k+1)for k = 0,1,.,90u(91+k)= p(k)for k = 0,1,2u(k)= 0for k = 185,186,187,188 (tail bits)SIST EN 300 909 V6.1.3:2003
ETSIEN 300 909 V6.1.3 (1999-03)13GSM 05.03 version 6.1.3 Release 19973.1.2.2Convolutional encoderThe class 1 bits are encoded with the 1/2 rate convolutional code defined by the polynomials:G0 = 1 + D3+ D4G1 = 1 + D + D3+ D4The coded bits {c(0), c(1),., c(455)} are then defined by:- class 1:c(2k)= u(k) + u(k-3) + u(k-4)c(2k+1)= u(k) + u(k-1) + u(k-3) + u(k-4) for k = 0,1,.,188u(k) = 0 for k < 0- class 2:c(378+k)= d(182+k)fork = 0,1,.,773.1.3InterleavingThe coded bits are reordered and interleaved according to the following rule:i(B,j) = c(n,k),fork
= 0,1,.,455n
= 0,1,.,N,N+1,.B = B0 + 4n + (k mod 8)j
= 2((49k) mod 57) + ((k mod 8) div 4)See table 1. The result of the interleaving is a distribution of the reordered 456 bits of a given data block, n = N, over 8blocks using the even numbered bits of the first 4 blocks (B = B0 + 4N + 0, 1, 2, 3) and odd numbered bits of the last 4blocks (B = B0 + 4N + 4, 5, 6, 7). The reordered bits of the following data block, n = N+1, use the even numbered bitsof the blocks B = B0 + 4N + 4, 5, 6, 7 (B = B0 + 4(N+1) + 0, 1, 2, 3) and the odd numbered bits of the blocks B = B0 +4(N+1) + 4, 5, 6, 7. Continuing with the next data blocks shows that one block always carries 57 bits of data from onedata block (n = N) and 57 bits of data from the next block (n = N+1), where the bits from the data block with the highernumber always are the even numbered data bits, and those of the data block with the lower number are the oddnumbered bits.The block of coded data is interleaved "block diagonal", where a new data block starts every 4th block and is distributedover 8 blocks.3.1.4Mapping on a BurstThe mapping is given by the rule:e(B,j) = i(B,j)ande(B,59+j) = i(B,57+j)for j = 0,1,.,56ande(B,57) = hl(B)ande(B,58) = hu(B)The two bits, labelled hl(B) and hu(B) on burst number B are flags used for indication of control channel signalling. Foreach TCH/FS block not stolen for signalling purposes:hu(B) = 0 for the first 4 bursts(indicating status of even numbered bits)hl(B)
= 0 for the last 4 bursts(indicating status of odd numbered bits)For the use of hl(B) and hu(B) when a speech frame is stolen for signalling purposes see subclause 4.2.5.3.2Speech channel at half rate (TCH/HS)The speech coder delivers to the channel encoder a sequence of blocks of data. In case of a half rate speech TCH, oneblock of data corresponds to one speech frame. Each block contains 112 bits, including 95 bits of class 1 (protectedbits), and 17 bits of class 2 (no protection), see tables 3a and 3b.SIST EN 300 909 V6.1.3:2003
ETSIEN 300 909 V6.1.3 (1999-03)14GSM 05.03 version 6.1.3 Release 1997The bits delivered by the speech coder are received in the order indicated in GSM 06.20 and have to be arrangedaccording to either table 3a or table 3b before channel encoding as defined in subclauses 3.2.1 to 3.2.4. The rearrangedbits are labelled {d(0),d(1),.,d(111)}. Table 3a has to be taken if parameter Mode = 0 (which means that the speechencoder is in unvoiced mode), while table 3b has to be taken if parameter Mode = 1, 2 or 3 (which means that the speechencoder is in voiced mode).3.2.1Parity and tailing for a speech framea)Parity bits:The most significant 22 class 1 bits d(73),d(74),.,d(94) are protected by three parity bits used for errordetection. These bits are added to the 22 bits, according to a cyclic code using the generator polynomial:g(D) = D3 + D + 1The encoding of the cyclic code is performed in a systematic form, which means that, in GF(2), the polynomial:d(73)D24 + d(74)D23 + . + d(94)D3 + p(0)D2 + p(1)D + p(2)where p(0), p(1), p(2) are the parity bits, when divided by g(D), yields a remainder equal to:1 + D + D2.b)Tail bits and reordering:The information and parity bits of class 1 are reordered, defining 104 information + parity + tail bits of class 1,{u(0),u(1),.,u(103)} defined by:u(k) = d(k)for k = 0,1,.,94u(k) = p(k-95)for k = 95,96,97u(k) = 0for k = 98,99,.,103 (tail bits)3.2.2Convolutional encoderThe class 1 bits are encoded with the punctured convolutional code defined by the mother polynomials:G4 = 1 + D2 + D3 + D5 + D6G5 = 1 + D + D4 + D6G6 = 1 + D + D2 + D3 + D4 + D6and the puncturing matrices:(1,0,1)for {u(0),u(1),.,u(94)} (class 1 information bits);and {u(98),u(99),.,u(103)} (tail bits).(1,1,1)for {u(95),u(96),u(97)} (parity bits)In the puncturing matrices, a 1 indicates no puncture and a 0 indicates a puncture.The coded bits {c(0),c(1),.,c(227)} are then defined by:class 1 information bits:c(2k)= u(k)+u(k-2)+u(k-3)+ (k-5)+u(k-6)c(2k+1)= u(k)+u(k-1)+u(k-2)+u(k-3)+u(k-4)+u(k-6)for k = 0,1,.,94;u(k) = 0 for k<0SIST EN 300 909 V6.1.3:2003
ETSIEN 300 909 V6.1.3 (1999-03)15GSM 05.03 version 6.1.3 Release 1997parity bits:c(3k-95)= u(k)+u(k-2)+u(k-3)+u(k-5)+u(k-6)c(3k-94)= u(k)+u(k-1)+u(k-4)+u(k-6)c(3k-93)= u(k)+u(k-1)+u(k-2)+u(k-3)+u(k-4)+u(k-6)for k = 95,96,97tail bits:c(2k+3)= u(k)+u(k-2)+u(k-3)+u(k-5)+u(k-6)c(2k+4)= u(k)+u(k-1)+u(k-2)+u(k-3)+u(k-4)+u(k-6)for k = 98,99,.,103class 2 information bits:c(k+211)= d(k+95)for k = 0,1,.,163.2.3InterleavingThe coded bits are reordered and interleaved according to the following rule:i(B,j) = c(n,k)fork = 0,1,.,227n = 0,1,.,N,N+1,.B = B0 + 2n + bThe values of b and j in dependence of k are given by table 4.The result of the interleaving is a distribution of the reordered 228 bits of a given data block, n = N, over 4 blocks usingthe even numbered bits of the first 2 blocks (B = B0+2N+0,1) and the odd numbered bits of the last 2 blocks (B =B0+2N+2,3). The reordered bits of the following data block, n = N + 1, use the even numbered bits of the blocks B =B0 + 2N + 2,3 (B = B0+2(N+1)+0,1) and the odd numbered bits of the blocks B = B0 + 2(N+1) + 2,3. Continuing withthe next data blocks shows that one block always carries 57 bits of data from one data block (n = N) and 57 bits from thenext block (n = N+1), where the bits from the data block with the higher number always are the even numbered data bits,and those of the data block with the lower number are the odd numbered bits. The block of coded data is interleaved"block diagonal", where a new data block starts every 2nd block and is distributed over 4 blocks.3.2.4Mapping on a burstThe mapping is given by the rule:e(B,j) = i(B,j) and e(B,59+j) = i(B,57+j) for j = 0,1,.,56ande(B,57) = hl(B) and e(B,58) = hu(B)The two bits, labelled hl(B) and hu(B) on burst number B are flags used for indication of control channel signalling. Foreach TCH/HS block not stolen for signalling purposes:hu(B) = 0for the first 2 bursts (indicating status of the even numbered bits)hl(B)
= 0for the last 2 bursts (indicating status of the odd numbered bits)For the use of hl(B) and hu(B) when a speech frame is stolen for signalling purposes, see subclause 4.3.5.3.3Data channel at full rate, 12.0 kbit/s radio interface rate (9.6kbit/s services (TCH/F9.6))The definition of a 12.0 kbit/s radio interface rate data flow for data services is given in GSM 04.21.3.3.1Interface with user unitThe user unit delivers to the encoder a bit stream organized in blocks of 60 information bits (data frames) every 5 ms.Four such blocks are dealt with together in the coding process {d(0),.,d(239)}. For non-transparent services those fourblocks shall align with one 240-bit RLP frame.SIST EN 300 909 V6.1.3:2003
ETSIEN 300 909 V6.1.3 (1999-03)16GSM 05.03 version 6.1.3 Release 19973.3.2Block codeThe block of 4 * 60 information bits is not encoded, but only increased with 4 tail bits equal to 0 at the end of the block.u(k) = d(k)for k = 0,1,.,239u(k) = 0for k = 240,241,242,243 (tail bits)3.3.3Convolutional encoderThis block of 244 bits {u(0),.,u(243)} is encoded with the 1/2 rate convolutional code defined by the followingpolynomials:G0 = 1 + D3 + D4G1 = 1 + D + D3+ D4resulting in 488 coded bits {C(0), C(1),., C(487)} withC(2k) = u(k) + u(k-3) + u(k-4)C(2k+1) = u(k) + u(k-1) + u(k-3) + u(k-4)for k = 0,1,.,243 ; u(k) = 0 for k < 0The code is punctured in such a way that the following 32 coded bits:{C(11+15j) for j = 0,1,.,31} are not transmitted.The result is a block of 456 coded bits, {c(0),c(1),., c(455)}3.3.4InterleavingThe coded bits are reordered and interleaved according to the following rule:i(B,j) = c(n,k)fork
= 0,1,.,455n
= 0,1,.,N,N + 1,.B
= B0 +4n + (k mod 19) + (k div 114)j
= (k mod 19) + 19 (k mod 6)The result of the interleaving is a distribution of the reordered 114 bit of a given data block, n = N, over 19 blocks, 6bits equally distributed in each block, in a diagonal way over consecutive blocks.Or in other words the interleaving is a distribution of the encoded, reordered 456 bits from four given input data blocks,which taken together give n = N, over 22 bursts, 6 bits equally distributed in the first and 22nd bursts, 12 bits distributedin the second and 21st bursts, 18 bits distributed in the third and 20th bursts and 24 bits distributed in the other 16bursts.The block of coded data is interleaved "diagonal", where a new block of coded data starts with every fourth burst and isdistributed over 22 bursts.3.3.5Mapping on a BurstThe mapping is done as specified for TCH/FS in subclause 3.1.4. On bitstealing by a FACCH, see subclause 4.2.5.3.4Data channel at full rate, 6.0 kbit/s radio interface rate(4.8 kbit/s services (TCH/F4.8))The definition of a 6.0 kbit/s radio interface rate data flow for data services is given in GSM 04.21.SIST EN 300 909 V6.1.3:2003
ETSIEN 300 909 V6.1.3 (1999-03)17GSM 05.03 version 6.1.3 Release 19973.4.1Interface with user unitThe user unit delivers to the encoder a bit stream organized in blocks of 60 information bits (data frames) every 10 ms,{d(0),d(1),.,d(59)}.In the case where the user unit delivers to the encoder a bit stream organized in blocks of 240 information bits every 40ms (e.g. RLP frames), the bits {d(0),d(1),.,d(59),d(60),.,
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