1、t ETSI I-ETS*300 034-1 93 = 3400855 OL20115 95b _._ ELECOMM UNICATION STANDARD I-ETS 300 034-1 October 1993 Source: ETSI TC-SMG UDC: 621.398.21 Key words: European digital telecommunication (GSM) Reference: GSM 05.08 system, Global System for Mobile communicati This version replaces the Interim Euro
2、pean Telecommunication Standard LETS 300 034 (March 1992) European digital cellular telecommunications system (phase 1 ); Radio sub-system link conto1 Part 1: Generic (GSM 05.08) ETSI European Telecommunications Standards Institute ETSI Secretariat Postal address: 06921 Sophia Antipolis Cedex - FRAN
3、CE Office address: Route des Lucioles - Sophia Antipolis - Valbonne - FRANCE Tel.: +33 92 94 42 O0 - Fax: +33 93 65 47 16 European Telecommunications Standards Institute 1 993. All rights reserved. No part may be reproduced except as authorised by written permission. The copyright and the foregoing
4、restriction on reproduction extend to all media in which the information may be embodied. ETSI I-ETS*3061 034-1 93 3400855 0120116 892 I-ETS 300 034-1 :I 993 4 , Whilst every care has been taken in the preparation and publication of this document, errors in content, typographical or otherwise, may o
5、ccur. If you have comments concerning its accuracy, please write to “ETSI Editing and Standards Approval Dept.“ at the address shown on the title page. . ETSI I-ETSx3QO 034-1 93 3400855 0120l117 729 M I-ETS 300 034-1 1993 Foreword As a result of an extension to this Interim European Telecommunicatio
6、n Standards (LETS) by Technical Committee Special Mobile Group (TC-SMG) it has become necessary to introduce an additional part to I-ETS 300 034. Because an additional part to this LETS has been introduced, this base standard is now identified by the additional wording “Part 1: Generic“ in the title
7、 and the original LETS number is followed by “-1“. Part 2 of LETS 300 034 describes the DCS 1800 extension of the radio sub-system link control, and is identified by additional wording in the title and by the LETS number, I-ETC 300 034-2. Further, due to an administrative error, LETS 300 034 has bee
8、n distributed encompassing the incorrect version of the GSM technical specification GSM 05.08. The incorrect version can be identified by the GSM version number 4.2.0 on the page headers. The correct adopted version is GSM 05.08 version 3.7.0 which is incorporated within this replacement I-ETS.This
9、I-ETS specifies the radio sub-system link control implemented in the Mobile Station (MS), Base Station (BS) and the Mobile services Switching Centre (MSC) within the European digital cellular telecommunications system (phase 1). Reference is made within this LETS to the following technical specifica
10、tions (NOTE 1): GSM 02.1 1 GSM 03.03: GSM 03.09 GSM 04.04 GSM 04.06 GSM 04.08 GSM 05.02 GSM 05.05 GSM 05.10 GSM 08.08 Service accessibility. Numbering addressing and identification. Handover procedures. MS-BSS Layer 1 - general requirements. MS-BSS data link layer specification. Mobile radio interfa
11、ce - layer 3 specification. Multiplexing and multiple access on the radio path. Radio transmission and reception. Radio sub-system synchronisation. BSS-MSC layer 3 specification. The above specifications, together with appendices A and B of this standard, are normative. NOTE 1: ETSI has constituted
12、stable and consistent documents which give technical specifications for the implementation of the European digital cellular telecommunications system. Historically, these documents have been identified as “GSM recommendations“. Some of these recommendations may subsequently become Interim European T
13、elecommunication Standards (I-ETSs) or European Telecommunication Standards (ETSs), whilst the others will be renamed ETSI-GSM Technical Specifications. These ETSI-GSM Technical Specifications are, for editorial reasons, still referred to as GSM recommendations in some current GSM documents. The num
14、bering and version control system used for ETSI-GSM Technical Specifications is the same as that used for GSM recommendations. NOTE 2: Items in this draft indicated as not compete or requiring further study or work, are not required for the Phase 1 implementation of the European digital cellular tel
15、ecommunications system. ETSI I-ETS*300 034-1 93 m 3400855 0120118 665 m I-ETS 300 034-1 1993 . ETSI I-ETS*300 034-1 93 D 3400855 0120LL9 5TL ETSI/GSM GSM 05.08 - /1 Version 3.7.0 Title RADIO SUB-SYSTEM LINK CONTROL b Pelease Date : January, 91 List of Contents : 1. 2. 3. 4. 5. 6. 7. 8. 9. Scope Gene
16、ral. Handover. RF Power control. Radio link failure. Cell selection and re-selection. Network pre-requisites. Radio link measurements. Control parameters. Original Language : English Number of pages : 38 Notes : Explanatory notes are contained in brackets l. ETSI I-ETS*300 034-1 93 = 3400855 0120120
17、 213 = ETSI/GSM GSM 05.08 - /2 Version 3.7 .O CONTENTS 1. SCOPE 2. GENERAL 3. HANDOVER 3.1 Overall process 3.2 MS measurement procedure 3.3 BS measurement procedure 3.4 Strategy 4. RF POWER CONTROL 4.1 Overall process 4.2 MS Implementation 4.3 MS Power Control Range 4.4 BS Implementation 4.5 BS Powe
18、r Control Range 4.6 Strategy 4.7 Timing 5. RADIO LINK FAILURE 5.1 Cri terion 5.2 MS Procedure 5.3 BS Procedure 6. 6.1 6 -2 6.3 6.4 6.5 6.6 6.7 6.8 CELL SELECTION AND RE-SELECTION. Overall process Cell Selection - No BCCH information available Cell Selection - BCCH information available Path loss cri
19、terion for cell selection and reselection Downlink signalling failure Cell Re-selection in Idle mode Release of TCH and SDCCH Abnormal cases and emergency calis 7. NETWORK PRE-REQUISITES 7.1 BCCH Carriers 7.2 Identification of Adjacent BSs for Handover Measurements 8. RADIO LINK MEASUREMENTS 8.1 Sig
20、nal Strength 8.2 Signal Quality 8.3 Aspects of discontinuous transmission (DTX) 8.4 Measurement reporting 8.5 Absolute MS-BS distance 9. CONTROL PARAMETERS App : A Definition of a basic GSM handover and RF power control algorithm. 1. 2. ETSI/GSM GSM 05.08 - /3 Version 3.7.0 SCOPE : This recommendati
21、on specifies the Radio sub-system link control implemented in the Mobile Station (MS), Base Station (BS) and Mobile Switching Centre (MSC) of the GSM system. GENERAL : The radio sub-system link control aspects that are addressed are as follows : - Handover - RF Power control - Radio link Failure - C
22、ell selection and re-selection in Idle mode. Handover is required to maintain a call in progress as a MS passes from one cell coverage area to another and may also be employed to meet network management requirements, e.g. relief of congestion. Handover may occur during a call from TCH to TCH, it may
23、 also occur from DCCH to DCCH, e.g. during the initial signalling period at call Set-up. The handover may be either from a channel on one cell to another channel on a surrounding cell, or between channels on the same cell. Examples are given of handover strategies, however, these will be determined
24、in detail by the network operator. Adaptive control of the RF transmit power from an MS and optionally from the BC is implemented in order to optimize the uplink and downlink performance and minimise the effects of Co-channel interference in the system. The criteria for determining radio link failur
25、e are specified in order to ensure that calls which fail either from loss of radio coverage or unacceptable interference are satisfactorily handled by the network. Radio link failure may result in either re-establishment or release of the call in progress. Procedures for cell selection and re-select
26、ion whilst in Idle mode (i.e not actively processing a call), are specified in order to ensure that a mobile is camped on a cell with which it can reliably communicate on both the radio uplink and downlink. Information signalled between the MS and BS is summarised in Tables 1 and 2. A full specifica
27、tion of the Layer 1 header is given in GSM Recommendation 04.04, and of the Layer 3 fields in GSM Recommendation 04.08. ETSI/GSM GSM 05.08 - /4 Version 3.7. O 3. “DOVER : 3.1 OVERALL PROCESS : The overall handover process is implemented in the MS, BS and . MSC. Measurement of radio subsystem downlin
28、k performance and signal strengths received from surrounding cells, is made in the MS. These measurements are signalled to the BS for assessment. The BS measures the uplink performance for the MS being served and also assesses the signal strength of interference on its idle traffic channels. Initial
29、 assessment of the measurements in conjunction with defined thresholds and handover strategy may be performed in the BS. Assessment requiring measurement results from other BSs or other information resident in the MSC, may be performed in the MSC. 4 GSM Recommendation 03.09 describes the handover pr
30、ocedures to be used in PLMNs. 3.2 MS MEASUREMENT PROCEDURE A procedure shall be implemented in the MS by which it monitors the downlink RX signal level and quality from its serving cell and the downlink RX signal level and BSIC of surrounding BSs. The method of identification of surrounding BSs is d
31、escribed in Section 7.2. The requirements for the MS measurements are given in section 8.1. 3.3 BS MEASUREMENT PROCEDURE : A procedure shall be implemented in the BS by which it monitors the uplink RX signal level and quality from each MS being served by the cell. A procedure shall be implemented by
32、 which the BS monitors the levels of interference on its idle traffic channels. 3.4 STRATEGY : The handover strategy employed by the network for radio link control determines the handover decision that will be made based on the measurement results reported by the MS/BS and various parameters set for
33、 each cell. Network directed handover may also occur for reasons other than radio link control, e.g. to control traffic distribution between cells. The exact handover strategies will be determined by the network operator, a detailed example of a basic overall algorithm appears in Appendix A. Possibl
34、e types of handover are as follows : ETSI I-ETS*300 034-1 93 3400855 0120123 T22 ETSI/GSM GSM 05.08 - /5 Version 3.7. O Inter-cell handover : 4. 4.1 4.2 Intercell handover from the serving cell to a surrounding cell will normally occur either when the handover measurements show low RXLEV and/or RXQU
35、AL on the current serving cell and a better RXLEV available from a surrounding cell, or when a surrounding cell allows communication with a lower TX power level. This typically indicates that an MS that is on the border of the cell area. Intra-cell handover : Intra-cell handover from one channel/tim
36、eslot in the serving cell to another channel/timeslot in the same cell will normally be performed if the handover measurements show a low RxQUAL, but a high RXLEV on the serving cell. This indicates a degradation of quality caused by interference even though the MS is situated within the serving cel
37、l. The intra-cell handover should provide a channel with a lower level of interference. Intra-cell handover can occur either to a timeslot on a new carrier or to a different timeslot on the same carrier. GSM Recommendation 08.08 defines the causes for handover that may be signalled from ES to MSC. R
38、F POWER CONTROL : OVERALL PROCESS : RF power control is employed to minimise the transmit power required by MS or BS whilst maintaining the quality of the radio links. By minimising the transmit power levels, interference to Co-channel users is reduced. MS IMPLEMENTATION : RF power control shall be
39、implemented in the MS. The RF power level to be employed by the MS is indicated by means of the 5 bit TXPWR field sent either in the layer 1 header of each downlink SACCH message block, or in a dedicated signalling block. The MS shall confirm the power level that it is currently employing by setting
40、 the MS-TXPWR-COW field in the uplink SACCH L1 header to its current power setting. The value of this field shall be the power setting actually used by the mobile for the last burst of the previous SACCH period. The MS shall employ the most recently commanded RF power level appropriate to the channe
41、l for all transmitted bursts on either a TCH (including handover access burst), FACCH, SACCH or SDCCH. ETSI I-ETS*300 034-1 93 3400855 0120324 969 ETSI/GSM GSM 05.08 - /6 Version 3.7.0 When accessing a cell on the RACH (random access) and before receiving the first power command during a communicati
42、on on a DCCH or TCH (after an IMMEDIATE ASSIGNMENT), the MS shall use either the power level defined by the MS-TXPWR-MAX-CCH parameter broadcast on the BCCH of the cell, or the maximum TXPWR of the MS as defined by its power class, whichever is the lower. 4.3 MS POWER CONTROL RANGE : The range over
43、which a MS shall be capable of varying its RF output power shall be from its maximum output down tc QmW, in steps of nominally 2dB. GSM Recommendation 05.05 gives a detailed definition OE -: RF power level step size and tolerances. 4.4 BS IMPLEMENTATION : RF power control may be optionally implement
44、ed in the ES. 4.5 BS POWER CONTROL RANGE : The range over which the BS shall be capable of reducing its RF output power from its maximum level shall be nominally 30dB, in 15 steps of nominally 2dB. GSM Recommendation 05.05 gives a detailed definition of the RF power level step size and tolerances. 4
45、.6 STRATEGY : The RF power control strategy employed by the network determines the TXPWR command that is signalled to the MS, and the RF power level that is employed by the BS. The RF power level to be employed in each case will be based on the measurement results reported by the MS/BS and various p
46、arameters set for each cell. The exact strategies will be determined by the network operator. A detailed example of a basic algorithm appears in Appendix A. 4.7 TIMING : Upon receipt of a command from the SACCH to change its RF power level (TXPWR field) the MS shall change to the new level at a rate
47、 of one nominal 2dB power step every 60ms (13 TDMA frames), i.e. a full range change of 15 steps should take about 900ms . The change shall commence at the first TDMA frame belonging to the next reporting period (as specified in 8.4). The MS shall change the power one nor L 2 dB step at a time, at a
48、 rate of one step every 60 ms following the initiai change, irrespective of whether a-.ial transmission takes place or not. In case of channel change the commanded power level shall be applied on the new channel immediately. 5. 5.1 5.2 _ ETSI I-ETSr300 034-1 93 m 3900855 0120125 8T5 W ETSI/GSM GSM 0
49、5.08 - /7 Version 3.7 .O 5.3 RADIO LINK FAILURE : CRITERION : The criterion for determining Radio Link Failure ln the MS shall be based on the success rate of decoding messages on the downlink SACCH. MS PROCEDURE : The radio link failure criterion is based on the radio link counter S. If the MS is unable to decode a SACCH message, S is decreased by 1. In the case of a successful reception of a SACCH message S is increased by 2. In any case S shall not exceed the value of RADIO-LINK-TIMEOUT. If S reaches O a radio link failure shall be declared. The action to be taken is spe
