SIST ETS 300 133-4:1999

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Paging Systems (PS); Enhanced Radio MEssage System (ERMES); Part 4: Air interface specification33.070.20Sistem za osebni klicPaging systemsICS:Ta slovenski standard je istoveten z:ETS 300 133-4 Edition 1SIST ETS 300 133-4:1999en01-september-1999SIST ETS 300 133-4:1999SLOVENSKI
STANDARD



SIST ETS 300 133-4:1999



EUROPEANETS 300 133-4TELECOMMUNICATIONJuly 1992STANDARDSource: ETSI TC-PSReference: DE/PS-2001-4ICS:33.080Key words:ERMES, radio subsystem, air interfacePaging Systems (PS);European Radio Message System (ERMES);Part 4 : Air interface specificationETSIEuropean Telecommunications Standards InstituteETSI SecretariatPostal address: F-06921 Sophia Antipolis CEDEX - FRANCEOffice address: 650 Route des Lucioles - Sophia Antipolis - Valbonne - FRANCEX.400: c=fr, a=atlas, p=etsi, s=secretariat - Internet: secretariat@etsi.frTel.: +33 92 94 42 00 - Fax: +33 93 65 47 16Copyright Notification: No part may be reproduced except as authorized by written permission. The copyright and theforegoing restriction extend to reproduction in all media.© European Telecommunications Standards Institute 1992. All rights reserved.SIST ETS 300 133-4:1999



Page 2ETS 300 133-4: July 1992Whilst every care has been taken in the preparation and publication of this document, errors in content,typographical or otherwise, may occur. If you have comments concerning its accuracy, please write to"ETSI Editing and Committee Support Dept." at the address shown on the title page.SIST ETS 300 133-4:1999



Page 3ETS 300 133-4: July 1992ContentsForeword.51Scope.72Normative references.73Definitions.74Abbreviations.95Transmission protocol.95.1General description of the protocol.95.2Outline of the air interface model.125.2.1Information format L4.125.2.2Error correction coding L3.125.2.3Codeword interleaving L2.125.2.4Modulation L1.125.3Application of the model to the air interface.125.4Batch structure.125.5Subsequence lengths.136Information format.146.1General.146.2Synchronisation partition.146.3System information partition.146.3.1System information.146.3.1.1Format of the network information.146.3.1.2Format of the time slot information.156.3.2Supplementary system information.156.3.2.1Supplementary system information field (SSIT=0000).156.3.2.2Supplementary system information field (SSIT=0001).166.4Address partition.166.5Message partition.166.5.1Message header.176.5.1.1Variable information field (AII=0).176.5.1.2Variable information field (AII=1).186.5.1.2.1Long messages (AII=1, AIT=001).186.5.1.2.2Remote programming of pager parameters (AII=1,AIT=010).186.5.1.2.3Miscellaneous (AII=1, AIT=100).196.5.1.2.4Common temporary address pointers (AII=1, AIT=111).206.5.2Additional information and external operator identity.206.5.3Message data.206.5.4Message delimiter.216.5.5Completion of message codeblocks.216.5.6Unused codeblocks.217Error correction coding.218Codeword interleaving.239Modulation.239.1General.239.2RF channels and channel numbering.23SIST ETS 300 133-4:1999



Page 4ETS 300 133-4: July 19929.3Modulation format.239.3.1Symbol alphabet.249.3.2Data rate and symbol rate.249.3.3Premodulation pulse shaping.249.3.4Paging receiver performance.259.3.5Transmitter performance.2510Operation of the radio subsystem.2610.1General.2610.2Frequency subset indicator and frequency subset number.2610.3Border area indicator.2710.4External traffic indicator.2710.5Examples of receiver operation.2710.5.1Non-locking receivers.2710.5.2Locking receiver.2811Paging message procedures on the air interface.2811.1General.2811.2Individual call procedure.2811.3Group call procedure.2911.4Handling of long messages.3011.5Messages continued in further batches in the same subsequence.3111.6Messages continued in further subsequences.3111.7Transmission of variable receiver parameters.3111.8Termination of message search.3111.8.1Individual calls.3111.8.2Group calls.3112Battery saving techniques.3212.1Batch level.3212.2Subsequence level.3212.3Cycle level.3212.4Sequence level.3213Synchronisation.3313.1General.3313.2Synchronisation between paging receiver and radio transmission.3313.3Synchronisation between base stations.3313.4Co-ordination between networks.34Annex A (normative): List of country or area numbers.35History.39SIST ETS 300 133-4:1999



Page 5ETS 300 133-4: July 1992ForewordThis European Telecommunication Standard (ETS) has been produced by the Paging Systems (PS)Technical Committee of the European Telecommunications Standards Institute (ETSI).This ETS comprises seven parts with the generic title "Paging systems; European Radio Message System(ERMES)". The title of each part is listed below:-ETS 300 133-1: "Part 1 - General aspects"-ETS 300 133-2: "Part 2 - Service aspects"-ETS 300 133-3: "Part 3 - Network aspects"-ETS 300 133-4: "Part 4 - Air interface specification"-ETS 300 133-5: "Part 5 - Receiver conformance specification"-ETS 300 133-6: "Part 6 - Base station specification"-ETS 300 133-7: "Part 7 - Operation and maintenance aspects"This part, ETS 300 133-4, specifies the radio subsystem aspects including:-the transmission protocol and its operation;-modulation characteristics;-channel coding;-quasi-synchronous operation;-receiver battery saving techniques.NOTE:In this part of the ERMES ETS, some protocol bits have been "reserved for futuredefinition". It is intended that these bits will be allocated for specific options in a futureenhanced version of the standard.Suggestions for potential enhancements to the protocol using these bits should becommunicated via the normal ETS maintenance procedures to the ETSI Secretariat atthe address given on the title page.SIST ETS 300 133-4:1999



Page 6ETS 300 133-4: July 1992Blank pageSIST ETS 300 133-4:1999



Page 7ETS 300 133-4: July 19921ScopeThis part of the seven part European Telecommunication Standard (ETS) 300 133 describes the radio airinterface specification of the European Radio Message System (ERMES). All aspects of the radiosubsystem are defined including the transmission protocol, information format, channel coding andmodulation characteristics. Operation of the radio subsystem and procedures on the air interface aredefined and described.2Normative referencesThis ETS incorporates by dated or undated reference, provisions from other publications. These normativereferences are cited at the appropriate places in the text and the publications are listed hereafter. Fordated references subsequent amendments to, or revisions of any of these
publications apply to this ETSonly when incorporated in it by amendment or revision. For undated references the latest edition of thepublication referred to applies.[1]ETS 300 133-2 (1992): "Paging Systems (PS); European Radio MessageSystem (ERMES) Part 2: Service aspects".[2]ETS 300 133-5: (1992) "Paging Systems (PS); European Radio MessageSystem (ERMES) Part 5: Receiver conformance specification".[3]ETS 300 133-6: (1992) "Paging Systems (PS); European Radio MessageSystem (ERMES) Part 6: Base station conformance specification".[4]CCITT Recommendation E.212 (1988): "Identification plan for land mobilestations", Annex A.[5]CEPT Recommendation T/R 25-07, Annex 1: "Frequency coordination for theEuropean radio message system (ERMES)".3DefinitionsFor the purposes of this part of ETS 300 133 the following definitions shall apply.Associated Operator: one of the network operators with which the home operator has an agreement toexclusively transfer calls.Basic RIC: the prime identity of a paging receiver allocated by the network operator when service isinitiated. It shall not be changed without safeguards against unauthorised changes.Batch number: the 4 bit number corresponding to a particular batch type. Batch type A shall correspondto batch number 0000. Batch type P shall correspond to batch number 1111.Batch type: the letter (A to P) which identifies one of the 16 batches within a subsequence.Codeblock: Nine codewords interleaved as a unit as used in the message partition.Codeword: the standard information unit of 30 bits length.Country code: binary representation of the country number defined in Annex A. The country code consistsof 7 bits. (See also subclause 6.3.1.1).End of Message (EOM) character: a specific character used to indicate the end of an alphanumericmessage. It corresponds to DC1 as defined in Annex C2 of ETS 300 133-5 [2].External Receiver: a receiver operating in a network which is not its home network.Frequency divided network: a network that uses different frequency channels in adjacent paging areas.SIST ETS 300 133-4:1999



Page 8ETS 300 133-4: July 1992Geographical Area: one or several paging areas in an operator network. Defined by agreements betweennetwork operators for internetwork roaming or by a single operator for roaming within his own network. Itis used for roaming and choice of destination supplementary services.Home Network:
the
operator
network
with
which
a
mobile subscriber
has
signed
a subscription.Home Operator: the network operator to which a specific user has subscribed.Initial Address: the 18 most significant bits of the local address.I1 interface: the radio interface between the base stations and the paging receivers.I2 interface: an interface between the Paging Area Controller and the Base Station.Local Address: the number used by a network to identify the receivers subscribed to it. It consists of 22bits. The four least significant bits of the local address denote the batch number of the receiver.Long Message: a message that has been split into two or more parts (sub-messages) for transmission.Operator code: the number used by the system on the radio path to identify an operator within a country.It consists of 3 bits.Operator Identity: the number used by the system on the radio path to identify the home operator of areceiver. It has a total length of 13 bits and consists of three parts, the zone code, the country code andthe operator code.Paging Area: the area controlled by a PAC. It is the minimum area to which a mobile subscriber ispermitted to subscribe in order to receive his paging messages.Paging Area Code: the number used by the system to identify the paging area.Paging Area Controller: functional entity controlling the base stations within one paging area.Paging Message: the tone-only, numeric, alpha-numeric or transparent data information sent to a pagingreceiver.Paging Signal: the signal sent on the radio path to a paging receiver.Radio Identity Code: the number used by the system on the radio path to identify the receiver(s) forwhich the paging message is intended. The RIC has a total length of 35 bits and consists of five parts: thezone code (3 bits), the country code (7 bits), the operator code (3 bits), the initial address (18 bits) andthe batch number (4 bits).Reserved for future definition: the bits indicated are not specified in this edition of the standard but maybe in future editions. The bits should be set to a default value of zero and not used to convey information.The function of any equipment shall be independent of these bits. No fixed pattern of reserved bits shouldbe assumed and no combination of reserved bits shall cause equipment to malfunction.Roaming Area: the geographical area where the mobile subscriber asks for his messages to betransmitted when he uses the roaming service.Service Area: the paging area(s) to which the mobile subscriber has subscribed and in which a pagingmessage will normally be transmitted.SIST ETS 300 133-4:1999



Page 9ETS 300 133-4: July 1992Sub-message: part of a long message. All sub-messages of any one long message carry the samemessage number.Symbol: two bits of information which are the basic unit of information on the air interface. It correspondsto one of the four modulation levels specified in subclause 9.3.1.Time divided network: a network that uses the same frequency channel during different sub-sequences(periods of a time cycle) in adjacent paging areas.Zone code: binary representation of the zone number defined in Annex A. The zone code consists of 3 bits(see also subclause 6.3.1.1).4AbbreviationsAIIAdditional Information IndicatorAIFAdditional Information FieldAINAdditional Information NumberAITAdditional Information TypeBAIBorder Area IndicatorBSBase StationCTACommon Temporary AddressCTAPCommon Temporary Address PointerEBExternal BitENLNumber of LSBs to be compared when operating outside home networkETIExternal Traffic IndicatorFSIFrequency Subset IndicatorFSNFrequency Subset NumberHNLNumber of LSBs to be compared when operating within home networkLSBLeast Significant BitMSBMost Significant BitOPIDOperator IdentityPAPaging AreaPRPreamblePACPaging Area ControllerRFRadio FrequencyRICRadio Identity CodeRSVDReserved bits for future definitionSMSubsequence maskSSIFSupplementary System Information FieldSSITSupplementary System Information TypeSSNSubsequence NumberUMIUrgent Message IndicatorUTCUniversal Time Co-ordinatedVIFVariable Information Field5Transmission protocol5.1General description of the protocolThe structure of the basic transmission protocol on channel one is illustrated in figure 1.A sequence of 60 minutes total duration and comprising 60 cycles shall be provided. Sequences shall beco-ordinated with the UTC so that on the hour a new sequence commences.A paging cycle of exactly one minute duration, co-ordinated with UTC, shall be used to allow the necessaryco-ordination between different networks. Receivers may listen to one or a few cycles in a sequence inorder to reduce battery consumption (see Clause 12).SIST ETS 300 133-4:1999



Page 10ETS 300 133-4: July 1992Each cycle shall be divided into five subsequences commencing at 12 second intervals. To allow co-ordination between networks the SSN=0 subsequence shall always be transmitted first after the UTCminute marker.The transmission of a subsequence may end before the full 12 seconds has elapsed. The subsequencelength may be reduced by a small amount to allow for transmitter switching times. Occasionally a greaterreduction may be made in order that test or system transmissions can be made by individual transmitters.Each subsequence shall be further divided into 16 batches labelled A-P. The receiver population should bedivided into 16 groups and each receiver allocated to one of the 16 batch types according to the 4 leastsignificant bits of its basic RIC. Further RICs used by this receiver shall be of the same batch type.Each receiver shall only be initially addressed in its own batch type transmission. When the receiverdetects its initial address it should wait on the same channel for the message to be sent. The messagemay be sent in the same batch, in any subsequent batch of the same subsequence or in the followingsubsequence (see subclause 11.6 regarding time-out conditions).An initial address may be transmitted more than once in the same batch (see subclause 11.2).The time of transmission of a particular batch type on each frequency channel is shifted by a single timebatch with respect to the others as shown in figure 2. Consequently a receiver can, if necessary, stepthrough the paging frequency channels without losing any messages.The first fifteen batches in every subsequence shall have length 154 codewords. The final batch in everysubsequence shall have length 190 codewords. This is so that messages in time divided networks may becompleted within a subsequence.Each batch is further subdivided into four partitions. These are the synchronisation, system information,address and message partitions. A detailed description of the batch structure is given in subclause 5.4 andthe contents of each partition specified in subclauses 6.2 to 6.5.6(48(1&(¸¶¶¶¶¶¶¶¶¶¶¶¾¶¶¶¶¶¶¶¶¶¶¶¾¶¶¶¶¶¶¶¶¶¶¶¾¶¶¶¶¶¶¶¶¶¶¶¾¶¶¶¶¶¶¶¶¶¶¶¹º¶¶¶¶¶¶¶¶¶¶¶¿¶¶¶¶¶¶¶¶¶¶¶À¶¶¶¶¶¶¶¶¶¶¶À¶¶¶¶¶¶¶¶¶¶¶¿¶¶¶¶¶¶¶¶¶¶¶»6(48(1&(¸¶¶¶¶¶¶¶¶¶¶¶¶¶¶¶¶¾¶¶¶¶¶¶¶¶¶¶¶¶¶¶¶¾¶¶¶¶¶¶¶¶¶¶¶¶¾¶¶¶¶¶¶¶¶¶¶¶¶¶¹º¶¶¶¶¶¶¶¶¶¶¶¶¶¶¶¶¿¶¶¶¶¶¶¶¶¶¶¶¶¶¶¶¿¶¶¶¶¶¶¶¶¶¶¶¶¿¶¶¶¶¶¶¶¶¶¶¶¶¶»Figure 1: Structure of the radio protocol on channel one.SIST ETS 300 133-4:1999



Page 11ETS 300 133-4: July 1992¼¶¶¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¹¼¶¶¶¶À¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¶À¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶»¼¶¶¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¹¼¶¶¶¶À¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¶À¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶»¼¶¶¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¹¼¶¶¶¶À¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¶À¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶»¼¶¶¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¹¼¶¶¶¶À¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¶À¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶»¼¶¶¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¹¼¶¶¶¶À¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¶À¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶»¼¶¶¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¹¼¶¶¶¶À¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¶À¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶»¼¶¶¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¹¼¶¶¶¶À¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¶À¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶»¼¶¶¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¹¼¶¶¶¶À¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¶À¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶»¼¶¶¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¹¼¶¶¶¶À¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¶À¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶»¼¶¶¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¹¼¶¶¶¶À¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¶À¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶»¼¶¶¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¹¼¶¶¶¶À¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¶À¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶»¼¶¶¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¹¼¶¶¶¶À¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¶À¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶»¼¶¶¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¹¼¶¶¶¶À¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¶À¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶»¼¶¶¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¹¼¶¶¶¶À¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¶À¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶»¼¶¶¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¹¼¶¶¶¶À¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¶À¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶»¼¶¶¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¶À¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¾¶¹º¶¶¶¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶¿¶»Figure 2: Channel synchronisation and the scanning procedureNOTE:The relation between RF channel frequencies and channel numbers is defined insubclause 9.2.SIST ETS 300 133-4:1999



Page 12ETS 300 133-4: July 19925.2Outline of the air interface modelThe air interface transmissions are organised in four levels:L4 - information format;L3 - error correction coding;L2 - codeword interleaving;L1 - modulation.5.2.1Information format L4Co-ordination of the basic paging system data and paging message data is performed at the formatinformation level. It is a way of arranging the transmitted data in a predefined format that will berecognised by the receivers.Throughout this standard the bit transmission order shall be from left to right. Accordingly the MostSignificant Bit (MSB), which is the left most bit, will be transmitted first. The Least Significant Bit (LSB) isthe right most bit and will be transmitted last.5.2.2Error correction coding L3Forward error correction coding adds redundancy to the transmitted codewords so that after demodulationand de-interleaving transmission errors may be detected and corrected.5.2.3Codeword interleaving L2Interleaving is the technique to spread burst errors that occur on radio channels subject to multipath/fadingand impulsive noise. This is achieved by changing the order of bits in the transmitted data stream so thaton reception any burst of errors that has occured is spread over several codewords and there is a chancethat some or all of them may be corrected. This is further described in Clause 8.5.2.4Modulation L1The function of the modulation level is to distribute by radio transmission the coded and formattedinformation from the base station transmitters to the paging receivers.5.3Application of the model to the air interfaceEach of the processing levels will be described in detail in the following clauses. Not all levels shall beapplied to all parts of the interface transmissions. This is best specified at the batch level (see figure 1)where the following shall apply:-synchronisation partition; L1 & L4;-system information partition; L1, L3 & L4;-address partition; L1, L3 and L4;-message partition; L1, L2, L3 and L4.5.4Batch structureThe synchronisation partition and system information partition are of fixed length. The boundary betweenthe address and message partitions can be altered depending on traffic type and density. The requirementfor codeword interleaving in the message partition imposes detailed constraints on the position of theboundary. As shown in Clause 8 the protocol specifies codeword interleaving to a depth of ninecodewords. Hence messages shall be assembled and transmitted in blocks of 9 codewords (which areSIST ETS 300 133-4:1999



Page 13ETS 300 133-4: July 1992called codeblocks) and the address partition/message partition boundary positioned to allow this. Unusedcodewords within an address partition shall be filled with Address Partition Terminators (APTs) as definedin subclause 6.4. Unused codewords within an interleaved message codeblock shall be filled with messagedelimiters as defined in subclause 6.5.4. Unused bits within a message codeword shall be filled asdescribed in subclause 6.5.3. The detailed composition of a batch is as follows:Ķ¶¶¾¶¶¶Ö¶¶¶¾¶¶¶¾¶¶¶Ö¶¶¶¶¶¶¶¶¶¾¶¶¶¶¶¶¶¶¶Ö¶¶¶¶¶¶¶¶¶¶¶¶¶¶¶¶¶¶¶¶¶Çʶ¶¶¿¶¶¶Ù¶¶¶¿¶¶¶¿¶¶¶Ù¶¶¶¶¶¶¶¶¶¿¶¶¶¶¶¶¶¶¶Ù¶¶¶¶¶¶¶¶¶¶¶¶¶¶¶¶¶¶¶¶¶Í0(66$*(PR- preamble worddefined in subclause 6.2SYN- synchronisation worddefined in subclause 6.2SI- system informationdefined in subclause 6.3.1SSI- supplementary systemdefined in subclause 6.3.2
informationIA- initial addressdefined in Clause 3APT- address partitiondefined in subclause 6.4
terminatorCODEBLOCK- interleaved messagesdefined in subclause 6.5I- number of initial addresses
0 £ I £ 139J- number of address partition terminatorsJ = 9 - MOD{(4+I),9)} where MOD {M,N} = M - N*INT(M/N) and INT returns theinteger part of a numberK- number of codeblocks in the message partitionK £ (149 - I - J)/9first 15 batches of a subsequenceK £ (185 - I - J)/9last batch of a subsequenceTypical values of parameters forTypical values of parameters forthe first 15 batches are:the last batch are:I=0J=5K=16 Ìmaximum No.I=0
J=5
K=20 Ìmaximum No.I=4J=1K=16 ìof messagesI=4
J=1
K=20 ìof messagesI=5J=9K=15I=22
J=1
K=18I=139J=1K=1 -max. No. ofI=139
J=1
K=5
-max. No. ofinitial addressesinitial addresses5.5Subsequence lengthsThe length of a subsequence shall be 12 seconds (2500 codewords).The duration of data transmission within the subsequence may, however, be less than this. In the case thatless than 2500 codewords are transmitted the number of transmitted codewords shall be 2500 minus aninteger multiple of 9 codewords.The minimum number of codewords that may be transmitted in a subsequence is zero, notwithstanding therequirements of subclauses 10.1 and 6.4.The minimum reduction in subsequence transmission length that may be made is 1 codeblock (9codewords (43,2ms)).SIST ETS 300 133-4:1999



Page 14ETS 300 133-4: July 19926Information format6.1GeneralEach batch consists of four partitions as illustrated in subclause 5.4. Details of how the paging data isorganised within each partition are defined in this Clause.6.2Synchronisation
...