1、ETSI EN 300 959 V8.1.2 (2001-02) European Standard (Telecommunications series) Digital cellular telecommunications system (Phase 2+); Modulation (GSM 05.04 version 8.1.2 Release 1999) Copyright European Telecommunications Standards Institute Provided by IHS under license with ETSINot for ResaleNo re
2、production or networking permitted without license from IHS-,-,-(GSM 05.04 version 8.1.2 Release 1999) 2 ETSI EN 300 959 V8.1.2 (2001-02) Reference RENKMG-020504Q8 Keywords Digital cellular telecommunications system, Global System for Mobile communications (GSM) ETSI 650 Route des Lucioles F-O6921 S
3、ophia Antipolis Cedex - FRANCE Tel.: +33 4 92 94 42 O0 Fax: +33 4 93 65 47 16 Siret No 348 623 562 00017 - NAF 742 C Association but non lucratif enregistre la Sous-prfecture de Grasse (06) No 7803/88 Important notice Individual copies of the present document can be downloaded from: Tt- present docu
4、ment may be made available in more than one electronic version or in print. In any case of existing perceived difference in contents between such versions, the reference version is the Portable Document Format (PDF). In case of dispute, the reference shall be the printing on ETSI printers of the PDF
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6、sent document, send your comment to: editor etsi.fr Copyright Notification No part may be reproduced except as authorized by written permission. The copyright and the foregoing restriction extend to reproduction in all media. 8 European Telecommunications Standards Institute 2001. All rights reserve
7、d. ETSI Copyright European Telecommunications Standards Institute Provided by IHS under license with ETSINot for ResaleNo reproduction or networking permitted without license from IHS-,-,-(GSM 05.04 version 8.1.2 Release 1999) 3 ETSI EN 300 959 V8.1.2 (2001-02) Contents Intellectual Property Rights
8、4 Foreword 4 1 1.1 1.2 2 2.1 2.2 2.3 2.4 2.5 2.6 3 3.1 3.2 3.3 3.4 3.5 3.6 Scope 5 References 5 Abbreviations 5 Modulation format for GMSK . 5 Modulating symbol rate . 5 Start and stop of the burst 5 Differential encoding . 6 Filtering 6 Output phase . 7 Modulation 7 Modulation format for 8PSK . 7 M
9、odulating symbol rate . 7 Symbol mapping . 7 Start and stop of the burst 8 Symbol rotation . 9 Pulse shaping 9 Modulation 9 Annex A (informative): Change control history 10 History . 11 ETSI Copyright European Telecommunications Standards Institute Provided by IHS under license with ETSINot for Resa
10、leNo reproduction or networking permitted without license from IHS-,-,-(GSM 05.04 version 8.1.2 Release 1999) 4 ETSI EN 300 959 V8.1.2 (2001-02) Intellectual Property Rights IPRs essential or potentially essential to the present document may have been declared to ETSI. The information pertaining to
11、these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found in ETSI SR O00 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. Lat
12、est updates are available on the ETSI Web server ClattD:/www.etsP.c/iDr. 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 O00 314 (or the updates on the ETSI
13、Web server) which are, or may be, or may become, essential to the present document. Foreword This European Standard (Telecommunications series) has been produced by ETSI Technical Committee Special Mobile Group (SMG). The present document specifies the modulation format used within the digital cellu
14、lar telecommunications system. The contents of the present document may be subject to continuing work within SMG and may change following formal SMG approval. Should SMG modify the contents of the present document it will then be re-submitted for formal approval procedures by ETSI with an identifyin
15、g change of release date and an increase in version number as follows: Version 8.x.y where: 8 GSM Phase 2+ Release 1999. x the second digit is incremented for changes of substance, i.e. technical enhancements, corrections, updates, etc.; y the third digit is incremented when editorial only changes h
16、ave been incorporated in the specification. National transposition dates Date of adoption of this EN Date of latest announcement of this EN (doa): Date of latest publication of new National Standard or endorsement of this EN (dop/e): Date of withdrawal of any conflicting National Standard (dow): 2 F
17、ebruary 2001 31 May 2001 30 November 2001 30 November 2001 ETSI Copyright European Telecommunications Standards Institute Provided by IHS under license with ETSINot for ResaleNo reproduction or networking permitted without license from IHS-,-,-(GSM 05.04 version 8.1.2 Release 1999) 5 ETSI EN 300 959
18、 V8.1.2 (2001-02) 1 Scope The modulator receives the bits ftom the encryption unit, see GSM 05.01 i, and produces an RF signal. The filtering of the Radio Frequency (RF) signal necessary to obtain the spectral purity is not defined, neither are the tolerances associated with the theoretical filter r
19、equirements specified. These are contained in GSM 05.05 4. 1 .I References The following documents contain provisions which, through reference in this text, constitute provisions of the present documen t. References are either specific (identified by date of publication, edition number, version numb
20、er, etc.) or non-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 same number. For this Release 1999 document,
21、 references to GSM documents are for Release 1999 versions (version 8.x.y). u1 GSM 01.04: “Digital cellular telecommunication system (Phase 2+); Abbreviations and acronyms“. GSM 05 .O1 : “Digital cellular telecommunication system (Phase 2+); Physical layer on the radio path General description“. GSM
22、 05.02: “Digital cellular telecommunication system (Phase 2+); Multiplexing and multiple access on the radio path“. GSM 05.05: “Digital cellular telecommunication system (Phase 2+); Radio transmission and reception “ . 121 131 141 1.2 Abbreviations Abbreviations used in the present document are list
23、ed in GSM 01.04 i. 2 2.1 Modulation format for GMSK Modulating symbol rate The modulating symbol rate is 1/T = 1 625/6 ksymb/s (i.e. approximately 270.833 ksymb/s), which corresponds to 1 625/6 kbit/s (i.e. 270.833 kbit/s). 2.2 Start and stop of the burst Before the first bit of the bursts as define
24、d in GSM 05.02 3 enters the modulator, the modulator has an internal state as if a modulating bit stream consisting of consecutive ones (di = 1) had entered the differential encoder. Also after the last bit of the time slot, the modulator has an internal state as if a modulating bit stream consistin
25、g of consecutive ones (di = 1) had continued to enter the differential encoder. These bits are called dummy bits and define the start and the stop of the active and the useful part of the burst as illustrated in figure 1. Nothing is specified about the actual phase of the modulator output signal out
26、side the useful part of the burst. ETSI Copyright European Telecommunications Standards Institute Provided by IHS under license with ETSINot for ResaleNo reproduction or networking permitted without license from IHS-,-,-(GSM 05.04 version 8.1.2 Release 1999) dummy bits 3 tail bits . 1 11 11 1 112 bi
27、t 6 ETSI EN 300 959 V8.1.2 (2001-02) 3 tail bits dummy bits DOO . . . . . . . . . . . .o00 I l l Output phase The useful part The active part I.:I / 11 11 11 . JI2 bit Figure 1 : Relation between active part of burst, tail bits and dummy bits. For the normal burst the useful part lasts for 147 modul
28、ating bits 2.3 Differential encoding Each data value di = (O, I/ is differentially encoded. The output of the differential encoder is: L& = di Odi-1 (di E (0,l) where O denotes modulo 2 addition. The modulating data value input to the modulator is: h ai = 1-24 (ai E -l,+l) 2.4 Fi I te ring The modul
29、ating data values as represented by Dirac pulses excite a linear filter with impulse response defined by: g(t) = h(t) * rect( -$ where the function rect(x) is defined by: rect( +) = - 1 forltl I Modulating bits d36, I Symbol parameter / I This is illustrated in figure 2. Q c I Figure 2: Symbol mappi
30、ng of modulating bits into 8PSK symbols. 3.3 Start and stop of the burst Before the first bit of the bursts as defined in GSM 05.02 3 enters the modulator, the state of the modulator is undefined. Also after the last bit of the burst, the state of the modulator is undefined. The tail bits (see GSM 0
31、5.02) define the start and the stop of the active and the useful part of the burst as illustrated in figure 3. Nothing is specified about the actual phase of the modulator output signal outside the useful part of the burst. 9 tail bits O10 111 1 10 . . O10 111 110 9 tail bits Output phase ETSI Copyr
32、ight European Telecommunications Standards Institute Provided by IHS under license with ETSINot for ResaleNo reproduction or networking permitted without license from IHS-,-,-(GSM 05.04 version 8.1.2 Release 1999) S(t) =i 9 t sin( nj g (t)dt), for O I t I 4T sin($-n jg(t)df), for 4T t IST O, else O
33、t-4Ts O ETSI EN 300 959 V8.1.2 (2001-02) 3.4 Symbol rotation The 8PSK symbols are continuously rotated with 3d8 radians per symbol before pulse shaping. The rotated symbols are defined as: h ji3n18 si = si .e 3.5 Pulse shaping The modulating 8PSK symbols Si as represented by Dirac pulses excite a li
34、near pulse shaping filter. This filter is a linearised GMSK pulse, i.e. the main component in a Laurant decomposition of the GMSK modulation. The impulse response is defined by: I O, else where and Tis the symbol period. The base band signal is (t) = C Si . C, (t-iT + $T) I The time reference t = O
35、is the start of the active part of the burst as shown in figure 3. This is also the start of the bit period of bit number O (the first tail bit) as defined in GSM 05.02 2. 3.6 Modulation The modulated RF carrier during the useful part of the burst is therefore: where E, is the energy per modulating
36、symbo1,fo is the centre frequency and 90 is a random phase and is constant during one burst. ETSI Copyright European Telecommunications Standards Institute Provided by IHS under license with ETSINot for ResaleNo reproduction or networking permitted without license from IHS-,-,-(GSM 05.04 version 8.1
37、.2 Release 1999) 10 ETSI EN 300 959 V8.1.2 (2001-02) Annex A (informative): Change control history Figure 3 replaced (as it was corrup Update to Version 8.1.2 fo ETSI Copyright European Telecommunications Standards Institute Provided by IHS under license with ETSINot for ResaleNo reproduction or net
38、working permitted without license from IHS-,-,-(GSM 05.04 version 8.1.2 Release 1999) 11 ETSI EN 300 959 V8.1.2 (2001-02) V8.1.0 V8.1.2 History October 2000 One-step Approval Procedure OAP 20010202: 2000-10-04 to 2001-02-02 February 2001 Publication ETSI Copyright European Telecommunications Standards Institute Provided by IHS under license with ETSINot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
