SIST EN 300 396-2 V1.2.1:2003

• Abstract:

  The standard contains the requirements for DMO Radio aspects and this version iincludes updates for synchronization and frequency tracking.

• Status: Published
• Publication Date: 30-Nov-2003
• ICS: 33.070.10 - Terrestrial Trunked Radio (TETRA)
• Technical Committee: SS EIT - Technical Board for the electrotechnical, information technology and telecommunications fields
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Dec-2003
• Due Date: 01-Dec-2003
• Completion Date: 01-Dec-2003
• Ref Project: ETSI EN 300 396-2 V1.2.1 (2002-07) - Terrestrial Trunked Radio (TETRA); Technical requirements for Direct Mode Operation (DMO); Part 2: Radio aspects

SIST EN 300 396-2 V1.2.1:2003 is the SIST adoption of ETSI EN 300 396-2, a European Telecommunications Standard for Terrestrial Trunked Radio (TETRA) Direct Mode Operation (DMO) radio aspects. It specifies the physical-layer and lower MAC requirements for the TETRA DMO mobile station-to-mobile station air interface, including modulation, RF transmission and reception, synchronization, channel coding, channel multiplexing, and radio link control.

It is the part of the TETRA DMO series that focuses on how the radio signal is built, sent, received, synchronized, and measured in practice. Engineers use it to design and test Direct Mode Mobile Station (DM-MS) behavior, and buyers or quality teams use it to check radio performance requirements for DMO equipment.

What does SIST EN 300 396-2 V1.2.1:2003 specify?

SIST EN 300 396-2 V1.2.1:2003 specifies the radio aspects of TETRA DMO for the DM-MS air interface. Clause 1 says it applies to the physical layer and lower MAC, and clause 4 explains how the radio functions are organized across the document.

The document is structured as follows:

• Clause 1 - Scope
• Clause 2 - References
• Clause 3 - Definitions and abbreviations
• Clause 4 - Radio aspects
• Clause 5 - Modulation
• Clause 6 - Radio transmission and reception
• Clause 7 - Radio subsystem synchronization
• Clause 8 - Channel coding and scrambling
• Clause 9 - Channel multiplexing for DM
• Clause 10 - Radio subsystem link control

That structure matters in practice because each part answers a different design question: how to modulate the signal, how to test the transmitter and receiver, how to keep mobiles synchronized, and how to map user and signalling traffic onto bursts and timeslots.

What are the key requirements of SIST EN 300 396-2 V1.2.1:2003?

Modulation and burst structure

SIST EN 300 396-2 V1.2.1:2003 uses π/4-DQPSK with a root-raised cosine modulation filter and a 36 kbit/s modulation rate. Clause 5 defines the symbol mapping, differential encoding, and filter shape, so implementers know exactly how bits become transmitted symbols.

Clause 9 defines the physical timing: the DM resource is organized into timeslots, frames, and multiframes, and the standard defines three burst types - Direct mode Normal Burst (DNB), Direct mode Linearization Burst (DLB), and Direct mode Synchronization Burst (DSB). In practice, this tells a designer where user data, signalling, preambles, training sequences, and tail bits belong in each burst.

RF transmitter and receiver performance

Clause 6 sets the transmitter and receiver expectations for DM-MS equipment operating in the 300 MHz to 1 GHz range. It covers carrier separation, antenna-connector test arrangements, power classes, unwanted conducted and radiated emissions, frequency tolerance, output power timing, and transmitter intermodulation attenuation.

For the receiver, clause 6 checks blocking, spurious response rejection, intermodulation response rejection, unwanted emissions, and performance under static and multipath conditions. It also defines the receiver performance measures used in practice - Bit Error Ratio (BER), Message Erasure Rate (MER), and Probability of Undetected Erroneous Message (PUEM) - so test reports can match the logical channel being evaluated.

Synchronization and frequency tracking

Clause 7 defines master and slave behavior in DMO. A master DM-MS provides timing and frequency reference through synchronization bursts, while a slave DM-MS aligns its burst transmission to the master.

The clause also defines the timebase counters Quarter symbol Number (QN), Symbol Number (SN), Timeslot Number (TN), and Frame Number (FN), and it sets accuracy expectations for the radio frequency reference source and timebase. In practice, this is what keeps a Direct Mode call aligned across mobiles and is especially important during changeover, pre-emption, and frequency efficient mode.

Channel coding, scrambling, and logical-channel mapping

Clause 8 defines the error-control chain: block coding, convolutional coding, interleaving, and scrambling. Different logical channels use different schemes, including signalling channels such as SCH/S, SCH/H, and SCH/F, and traffic channels such as TCH/7,2, TCH/4,8, TCH/2,4, and TCH/S.

Clause 9 maps those logical channels onto physical bursts and blocks. That matters because it tells implementers how much redundancy, interleaving depth, and burst capacity each service uses.

What terms does SIST EN 300 396-2 V1.2.1:2003 define?

• Direct Mode Operation (DMO) - A simplex mode where mobile subscriber radios communicate directly outside the control of the TETRA V+D network.
• Direct Mode Mobile Station (DM-MS) - The mobile equipment used to obtain TETRA DM services.
• DM channel - A grouping of timeslots in the DM multiplex structure for a particular DM RF carrier.
• frequency efficient mode - A mode where two independent DM communications share one RF carrier, using channel A and channel B.
• Synchronization Signalling CHannel (SCH/S) - The signalling channel used for synchronization messages.
• Traffic CHannel (TCH) - A logical channel carrying user traffic such as speech or data.
• Probability of synchronization burst ACQuisition (PACQ) - The probability that a receiver detects and decodes a synchronization burst correctly.

Who uses SIST EN 300 396-2 V1.2.1:2003?

SIST EN 300 396-2 V1.2.1:2003 is used by TETRA terminal designers, RF engineers, protocol and baseband developers, and test laboratories working on DMO equipment. It is also useful to conformity and quality teams verifying transmitter power, emissions, receiver sensitivity, synchronization, and burst formatting.

In procurement and system integration, it helps buyers and integrators compare DM-MS products against the same radio behavior, especially when the equipment must support direct voice or data operation without a base station.

What changed in SIST EN 300 396-2 V1.2.1:2003 from the previous edition?

SIST EN 300 396-2 V1.2.1:2003 replaces ETSI EN 300 396-2 V1.2.0. The scope notes that this version includes updates for synchronization and frequency tracking.

Which standards are used with SIST EN 300 396-2 V1.2.1:2003?

• ETSI ETS 300 113 - Provides radio equipment technical characteristics and test conditions used for receiver-related definitions and intermodulation-related references.
• ETSI ETS 300 396-3 - Defines the TETRA DMO Mobile Station to Mobile Station Air Interface protocol that complements the radio layer and is used for SCH/S quality assessment in clause 10.
• ETSI ETS 300 395-2 - Defines the TETRA speech codec used for the full-rate traffic channel in the speech traffic channel clauses.

What does the SIST EN 300 396-2 V1.2.1:2003 document contain?

The document contains a reference configuration for the TETRA DM transmission chain, plus figures for the DM frame structure, burst timing, modulation process, time mask, error-control structure, and burst formats. It also contains tables for power classes, emission limits, receiver performance limits, propagation models, and logical-channel mapping.

Those tables and figures are used for design, RF testing, and conformance checking. In practice, they tell a laboratory what to measure, what test conditions to apply, and how each logical channel should be built into a transmitted burst.

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.QDþLQTerrestrial Trunked Radio (TETRA); Technical requirements for Direct Mode Operation (DMO); Part 2: Radio aspects33.070.10Prizemni snopovni radio (TETRA)Terrestrial Trunked Radio (TETRA)ICS:Ta slovenski standard je istoveten z:EN 300 396-2 Version 1.2.1SIST EN 300 396-2 V1.2.1:2003en01-december-2003SIST EN 300 396-2 V1.2.1:2003SLOVENSKI
STANDARD
ETSI ETSI EN 300 396-2 V1.2.1 (2002-07) 2
Reference REN/TETRA-08063 Keywords air interface, radio, tetra ETSI 650 Route des Lucioles F-06921 Sophia Antipolis Cedex - FRANCE
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Important notice Individual copies of the present document can be downloaded from: http://www.etsi.org The present document may be made available in more than one electronic version or in print. In any case of existing or 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 version kept on a specific network drive within ETSI Secretariat. Users of the present document should be aware that the document may be subject to revision or change of status. Information on the current status of this and other ETSI documents is available at http://portal.etsi.org/tb/status/status.asp If you find errors in the present document, send your comment to: [e-mail] 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.
© European Telecommunications Standards Institute 2002. All rights reserved.
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ETSI ETSI EN 300 396-2 V1.2.1 (2002-07) 3
Contents Intellectual Property Rights.6 Foreword.6 1 Scope.7 2 References.7 3 Definitions and abbreviations.7 3.1 Definitions.7 3.2 Abbreviations.8 4 Radio aspects.9 4.1 Introduction.9 4.2 Set of logical channels.9 4.3 Reference configuration.9 4.4 Error control schemes.10 4.5 Timeslot structure.10 4.5.1 Framing structure.10 4.5.2 Timeslots and bursts.11 4.5.3 Mapping of logical channels onto physical channels.11 4.6 Coding, interleaving and scrambling.11 4.7 Modulation.11 4.8 Transmission and reception.11 4.9 Other radio-related functions.11 4.10 Performance.11 5 Modulation.12 5.1 Introduction.12 5.2 Modulation type.12 5.3 Modulation rate.12 5.4 Modulation symbol definition.12 5.5 Modulated signal definition.13 5.6 Modulation filter definition.13 5.7 Modulation block diagram.14 6 Radio transmission and reception.14 6.1 Introduction.14 6.2 Frequency bands and channel arrangement.14 6.3 Reference test planes.14 6.4 Transmitter characteristics.14 6.4.1 Output power.14 6.4.2 Power classes.15 6.4.3 Unwanted conducted emissions.15 6.4.3.1 Definitions.15 6.4.3.2 Unwanted emissions close to the carrier.15 6.4.3.2.1 Emissions during the useful part of the burst.16 6.4.3.2.2 Emissions during the switching transients.16 6.4.3.3 Unwanted emissions far from the carrier.16 6.4.3.3.1 Discrete spurious.16 6.4.3.3.2 Wideband noise.17 6.4.3.4 Unwanted emissions during the Linearization CHannel (LCH).18 6.4.3.5 Unwanted emissions in the non-transmit state.18 6.4.4 Unwanted radiated emissions.18 6.4.5 Radio frequency tolerance.18 6.4.6 RF output power time mask.18 6.4.7 Transmitter intermodulation attenuation.19 6.4.7.1 Definition.19 6.4.7.2 Specification.19 6.5 Receiver characteristics.20 SIST EN 300 396-2 V1.2.1:2003

ETSI ETSI EN 300 396-2 V1.2.1 (2002-07) 4
6.5.1 Blocking characteristics.20 6.5.1.1 Definition.20 6.5.1.2 Specification.20 6.5.2 Spurious response rejection.20 6.5.2.1 Definition.20 6.5.2.2 Specification.20 6.5.3 Intermodulation response rejection.21 6.5.3.1 Definition.21 6.5.3.2 Specification.21 6.5.4 Unwanted conducted emissions.21 6.5.4.1 Definition.21 6.5.4.2 Specification.21 6.5.5 Unwanted radiated emissions.21 6.6 Transmitter/receiver performance.22 6.6.1 Modulation accuracy.22 6.6.1.1 Ideal case.22 6.6.1.2 Vector error magnitude requirement at symbol time.22 6.6.2 Receiver performance.23 6.6.2.1 Nominal error rates.23 6.6.2.2 Dynamic reference sensitivity.24 6.6.2.3 Receiver performance at reference interference ratios.24 6.6.2.4 Static reference sensitivity.25 6.6.2.5 MS receiver performance for acquisition of synchronization burst.25 6.6.3 Propagation conditions.26 6.6.3.1 Tap-gain process types.26 6.6.3.2 DM propagation models.26 7 Radio sub-system synchronization.27 7.1 Introduction.27 7.2 Definitions and general requirements for synchronization of DM-MSs.27 7.3 Timebase counters.28 7.3.1 Definition of counters.28 7.3.2 Relationship between the counters.28 7.4 Requirements for the frequency reference source of DM mobiles.28 7.5 Requirements for the synchronization of a slave DM mobile.28 7.6 Synchronization requirements for a master MS operating on channel B in frequency efficient mode.29 8 Channel coding and scrambling.29 8.1 Introduction.29 8.2 General.30 8.2.1 Interfaces in the error control structure.30 8.2.2 Notation.31 8.2.3 Definition of error control codes.31 8.2.3.1 16-state Rate-Compatible Punctured Convolutional (RCPC) codes.31 8.2.3.1.1 Encoding by the 16-state mother code of rate 1/4.32 8.2.3.1.2 Puncturing of the mother code.32 8.2.3.1.3 Puncturing scheme of the RCPC code of rate 2/3.32 8.2.3.1.4 Puncturing scheme of the RCPC code of rate 292/432.32 8.2.3.1.5 Puncturing scheme of the RCPC code of rate 148/432.32 8.2.3.2 (K1 + 16, K1) block code.33 8.2.4 Definition of interleaving schemes.33 8.2.4.1 Block interleaving.33 8.2.4.2 Interleaving over N blocks.33 8.2.5 Definition of scrambling.34 8.2.5.1 Scrambling method.34 8.2.5.2 Scrambling sequence.34 8.3 Error control schemes.34 8.3.1 Signalling channels.35 8.3.1.1 Synchronization Signalling CHannel (SCH/S).35 8.3.1.2 Half-slot Signalling CHannel (SCH/H) and Stealing CHannel (STCH).36 8.3.1.3 Full-slot Signalling CHannel (SCH/F).36 8.3.2 Traffic channels in circuit switched mode.37 SIST EN 300 396-2 V1.2.1:2003

ETSI ETSI EN 300 396-2 V1.2.1 (2002-07) 5
8.3.2.1 Traffic channel, net rate = 7,2 kbit/s (TCH/7,2).37 8.3.2.2 Traffic channel, net rate = 4,8 kbit/s (TCH/4,8).38 8.3.2.3 Traffic channel, net rate = 2,4 kbit/s (TCH/2,4).39 8.3.2.4 Speech Traffic Channel, full slot (TCH/S).39 8.3.2.5 Speech Traffic Channel, half slot (TCH/S).40 9 Channel multiplexing for DM.40 9.1 Introduction.40 9.2 Logical channels.40 9.2.1 Logical channels hierarchy.40 9.2.2 Traffic channels.40 9.2.3 Control channels.41 9.2.3.1 General.41 9.2.3.2 Linearization CHannel (LCH).41 9.2.3.3 Signalling CHannel (SCH).41 9.2.3.4 STealing CHannel (STCH).41 9.3 The physical resource.41 9.3.1 General.41 9.3.2 Timeslots.42 9.3.3 DM frame.42 9.3.4 Multiframe.42 9.4 Physical channels.42 9.4.1 General.42 9.4.2 Bursts.42 9.4.2.1 General.42 9.4.2.2 Modulation symbol numbering.42 9.4.2.3 Modulation bit numbering.42 9.4.2.4 Burst timing.43 9.4.3 Type of bursts.43 9.4.3.1 General.43 9.4.3.2 Modulation bits allocation.44 9.4.3.2.1 DM Normal Burst (DNB).44 9.4.3.2.2 DM Linearization Burst (DLB).44 9.4.3.2.3 DM Synchronization Burst (DSB).44 9.4.3.3 Burst fields.45 9.4.3.3.1 Frequency correction field.45 9.4.3.3.2 Inter-slot frequency correction field.45 9.4.3.3.3 Normal training sequence and preamble.45 9.4.3.3.4 Synchronization training sequence.46 9.4.3.3.5 Phase adjustment bits.46 9.4.3.3.6 Tail bits.46 9.4.4 DM-MS multiple slot transmission.46 9.4.5 General mapping of logical channels.47 10 Radio subsystem link control.47 10.1 Introduction.47 10.2 RF power control.47 10.3 Radio link measurements.47 10.3.1 Signal strength.47 10.3.2 Signal quality.47 History.48
ETSI ETSI EN 300 396-2 V1.2.1 (2002-07) 6
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://webapp.etsi.org/IPR/home.asp). 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 European Standard (Telecommunications series) has been produced by ETSI Project Terrestrial Trunked Radio (TETRA). The present document is part 2 of a multi-part deliverable covering the Terrestrial Trunked Radio (TETRA); Technical requirements for Direct Mode Operation (DMO), as identified below: Part 1: "General network design"; Part 2: "Radio aspects"; Part 3: "Mobile Station to Mobile Station (MS-MS) Air Interface (AI) protocol"; Part 4: "Type 1 repeater air interface"; Part 5: "Gateway air interface"; Part 6: "Security"; Part 7: "Type 2 repeater air interface"; Part 8: "Protocol Implementation Conformance Statement (PICS) proforma specification"; Part 9: "Service and Description Language (SDL) model"; Part 10: "Managed Direct Mode Operation (M-DMO)".
National transposition dates Date of adoption of this EN: 19 July 2002 Date of latest announcement of this EN (doa): 31 October 2002 Date of latest publication of new National Standard or endorsement of this EN (dop/e):
30 April 2003 Date of withdrawal of any conflicting National Standard (dow): 30 April 2003
ETSI ETSI EN 300 396-2 V1.2.1 (2002-07) 7
1 Scope EN 300 396 defines the TErrestrial Trunked RAdio system (TETRA) Direct Mode Operation (DMO). It specifies the basic air interface, the interworking between Direct Mode (DM) groups via repeaters, and interworking with the TETRA Voice plus Data (V+D) system via gateways. It also specifies the security aspects in TETRA DMO, and the intrinsic services that are supported in addition to the basic bearer and teleservices. The present document applies to the TETRA DMO Mobile Station - Mobile Station (MS - MS) air interface and contains the specifications of the physical layer according to the OSI seven layer reference model.
It establishes the TETRA DM radio aspects (layer 1 and lower MAC): - it defines and specifies the modulation; - it defines and specifies the radio transmission and reception; - it defines and specifies the synchronization; - it defines and specifies the channel coding; - it defines and specifies the channel multiplexing; - it defines and specifies the control over the radio link. 2 References The following documents contain provisions which, through reference in this text, constitute provisions of the present document. • References are either specific (identified by date of publication and/or edition number or version number) or non-specific. • For a specific reference, subsequent revisions do not apply. • For a non-specific reference, the latest version applies. [1] ETSI ETS 300 113: "Radio Equipment and Systems (RES); Land mobile service; Technical characteristics and test conditions for radio equipment intended for the transmission of data (and speech) and having an antenna connector". [2] ETSI ETS 300 396-3: "Terrestrial Trunked Radio (TETRA); Technical requirements for Direct Mode Operation (DMO); Part 3: Mobile Station to Mobile Station (MS-MS) Air Interface (AI) protocol". [3] ETSI ETS 300 395-2: "Terrestrial Trunked Radio (TETRA); Speech codec for full-rate traffic channel; Part 2: TETRA codec". 3 Definitions and abbreviations 3.1 Definitions For the purposes of the present document, the following terms and definitions apply: Bit Error Ratio (BER): ratio of the bits wrongly received to all bits received in a given logical channel call transaction: all of the functions associated with a complete unidirectional transmission of information during a call NOTE: A call is made up of one or more call transactions. In a simplex call these call transactions are sequential. SIST EN 300 396-2 V1.2.1:2003

ETSI ETSI EN 300 396-2 V1.2.1 (2002-07) 8
Direct Mode Operation (DMO): mode of simplex operation where mobile subscriber radio units may communicate using radio frequencies which may be monitored by, but which are outside the control of, the TETRA V+D network NOTE: Direct Mode Operation is performed without intervention of any base station. Direct Mode Mobile Station (DM-MS): physical grouping that contains all of the mobile equipment that is used to obtain TETRA DM services NOTE: For synchronization purposes, Direct Mode Mobile Stations can have one of two status levels: - master: if the DM-MS is either active in a call transaction transmitting traffic or control data, or is reserving the channel by means of channel reservation signalling and hence is providing synchronization information to the channel; - slave: if the DM-MS is receiving traffic and/or signalling and hence is deriving synchronization information from the channel. DM channel: specific grouping of timeslots in the DM multiplex structure related to a particular DM RF carrier (i.e. DM frequency) NOTE: The grouping may not always be fixed, but in DMO when operating in frequency efficient mode as an example, there are two DM channels, identified by the letters A and B.
frequency efficient mode: mode of operation where two independent DM communications are supported on a single RF carrier NOTE: In frequency efficient mode the two DM channels are identified as channel A and channel B. logical channel: generic term for any distinct data path NOTE: Logical channels are considered to operate between logical endpoints. Message Erasure Rate (MER): ratio of the messages detected as wrong by the receiver to all messages received in a given logical channel normal mode: mode of operation where only one DM communication is supported on an RF carrier Probability of Undetected Erroneous Message (PUEM): limit ratio of the erroneous messages detected as right by the receiver to all messages received in a given logical channel quarter symbol number: timing of quarter symbol duration 125/9 µs within a burst simplex: mode of working in which information can be transferred in both directions but not at the same time timebase: device which determines the timing state of signals transmitted by a Direct Mode Mobile Station timeslot number: counter indicating the timing of timeslots within a DMO frame useful part of a burst: part of the burst between and including the symbol time of SN0 and the symbol time of SNmax, with SN0 and SNmax as defined in clause 9 of EN 300 396-2 3.2 Abbreviations For the purposes of the present document, the following abbreviations apply: AI Air Interface BER Bit Error Ratio BN Bit Number DLB Direct mode Linearization Burst DLL Data Link Layer DM-MS Direct Mode Mobile Station DMO Direct Mode Operation DNB Direct mode Normal Burst DQPSK Differential Quaternary Phase Shift Keying DSB Direct mode Synchronization Burst SIST EN 300 396-2 V1.2.1:2003

ETSI ETSI EN 300 396-2 V1.2.1 (2002-07) 9
FN Frame Number LCH Linearization CHannel MER Message Erasure Rate mod modulo (base for counting) MS Mobile Station PACQ Probability of synchronization burst ACQuisition PUEM Probability of Undetected Erroneous Message QN Quarter symbol Number RCPC Rate-Compatible Punctured Convolutional RF Radio Frequency RMS Root Mean Square SCH Signalling CHannel SN Symbol Number STCH STealing CHannel TCH Traffic CHannel TN Timeslot Number V+D Voice plus Data 4 Radio aspects 4.1 Introduction This clause is an introduction to the radio aspects of the TETRA DMO standard. It consists of a general description of the organization of the radio-related functions with reference to the clauses where each part is specified in detail. Furthermore, it introduces the reference configuration that will be used throughout the present document. 4.2 Set of logical channels The radio subsystem provides a certain number of logical channels as defined in clause 9. The logical channels represent the interface between the protocol and the radio. 4.3 Reference configuration For the purpose of elaborating the specification of the radio-related functions, a reference configuration of the transmission chain is used, as shown in figure 1. Only the transmission part is specified, the receiver being specified only via the overall performance requirements. With reference to this configuration, the clauses address the following functional units: - clause 5:
differential encoding and modulation; - clause 6:
characteristics of transmitter and receiver; - clause 8:
coding, reordering and interleaving, and scrambling; - clause 9:
burst building and logical channel multiplexing; - clause 10:
radio link measurements. This reference configuration also defines a number of points of vocabulary in relation to the names of bits at different levels in the configuration. SIST EN 300 396-2 V1.2.1:2003

ETSI ETSI EN 300 396-2 V1.2.1 (2002-07) 10 RE-ORDERER ANDINTERLEAVERBLOCK ENCODERCONVOLUTIONALENCODERLOGICAL CHANNELMULTIPLEXER(1)(3)(2)(4)(5)(6)(7)(8)MODULATORDIFFERENTIALENCODER(1) type-1 information bits (transmit)(2) type-2 block encoded bits(3) type-3 convolutionally encoded bits(7) modulation bits(8) modulation symbolsSCRAMBLER(6) multiplexed bits(5) type-5 scrambled bits(4) type-4 re-ordered and interleaved bitsBURST BUILDERTRANSMITTER Figure 1: Reference configuration 4.4 Error control schemes The different error control schemes are described in detail in clause 8. 4.5 Timeslot structure The carrier separation is 25 kHz. The basic radio resource is a timeslot lasting 14,167 ms (85/6 ms) and transmitting information at a modulation rate of 36 kbit/s. This means that the timeslot duration, including guard and ramping times, is 510 bit (255 symbol) durations. The following clauses briefly introduce the structures of multiframes, frames, timeslots and bursts, as well as the mapping of the logical channels onto the physical channels. The appropriate specifications are found in clause 9. 4.5.1 Framing structure A diagrammatic representation of the framing structure is shown in figure 2. 3412173121 frame
= 4 timeslots ( ~
ms )1 multiframe
= 18 frames
( =
)1 time slot = 510 modulation bits durations
( ~
ms )1 modulation bit duration = 250/9
µs (~
µs)12350951845104control frame1,02 s27,7856,6714,167 Figure 2: DM framing structure SIST EN 300 396-2 V1.2.1:2003

ETSI ETSI EN 300 396-2 V1.2.1 (2002-07) 11 One multiframe is subdivided into 18 frames, and has a duration of 1,02 s. The eighteenth frame in a multiframe is a control frame. One frame is subdivided into 4 timeslots, and has a duration of 170/3 ≈ 56,67 ms. 4.5.2 Timeslots and bursts The timeslot is a time interval of 85/6 ≈ 14,167 ms, which corresponds to 255 symbol durations. The physical contents of a timeslot is carried by a burst. There are three different types of bursts, as defined in clause 9. 4.5.3 Mapping of logical channels onto physical channels The mapping of the logical channels onto the physical channels, according to the mode of operation, is defined in clause 9. 4.6 Coding, interleaving and scrambling The coding, interleaving and scrambling schemes associated with each logical channel are specified in clause 8. 4.7 Modulation The modulation scheme is π/4-DQPSK (Differential Quaternary Phase-Shift Keying) with root-raised cosine modulation filter and a roll-off factor of 0,35. The modulation rate is 36 kbit/s. This scheme is specified in detail in clause 5. 4.8 Transmission and reception The modulated stream is transmitted on a radio frequency carrier. The specific RF channels, together with the requirements on the transmitter and the receiver characteristics are specified in clause 6. DM-MS power classes are defined in clause 6. 4.9 Other radio-related functions Transmission involves other functions. These functions, which may necessitate the handling of specific protocols, are the radio subsystem synchronization, and the radio subsystem link control. The synchronization incorporates: - frequency and time acquisition by the receiver; - adjustment of the timebase in the DM-MS. The requirements on synchronization are specified in clause 7. 4.10 Performance Under typical urban fading conditions the quality threshold for full-rate speech is reached at a C/Ic (co-channel interference) value of 19 dB, and the dynamic reference sensitivity level is -103 dBm for mobile equipment. Details of performance requirements in various channel conditions are given in clause 6. SIST EN 300 396-2 V1.2.1:2003

ETSI ETSI EN 300 396-2 V1.2.1 (2002-07) 12 5 Modulation 5.1 Introduction The following specifications apply to the baseband part of the transmitter. 5.2 Modulation type The modulation used shall be π/4-shifted Differential Quaternary Phase Shift Keying (π/4-DQPSK). 5.3 Modulation rate The modulation rate shall be 36 kbit/s. 5.4 Modulation symbol definition B(m) denotes the modulation bit of a sequence to be transmitted, where m is the bit number. The sequence of modulation bits shall be mapped onto a sequence of modulation symbols S(k), where k is the corresponding symbol number. The modulation symbol S(k) shall result from a differential encoding. This means that S(k) shall be obtained by applying a phase transition Dφ(k) to the previous modulation symbol S(k-1), hence, in complex notation:
SkSkjDk()()exp(())=−1φ
S()01= (1) The above expression for S(k) corresponds to the continuous transmission of modulation symbols carried by an arbitrary number of bursts. The symbol S(0) is the symbol before the first symbol of the first burst and shall be transmitted as a phase reference.
The phase transition Dφ(k) shall be related to the modulation bits as shown in table 1 and figure 3. Table 1: Phase transitions B(2k-1) B(2k) Dφφφφ(k) 1 1 -3π/4 0 1 +3π/4 0 0 +π/4 1 0 -π/4
ReImS(k)π/2π/4−π/4−π/2π3π/4−3π/40 Figure 3: Modulation symbol constellation and possible transitions SIST EN 300 396-2 V1.2.1:2003

ETSI ETSI EN 300 396-2 V1.2.1 (2002-07) 13 The complex modulation symbol S(k) shall take one of the eight values exp(j nπ/4), where n = 2, 4, 6, 8 for even k and n = 1, 3, 5, 7 for odd k. The constellation of the modulation symbols and the possible transitions between them are as shown in figure 3. 5.5 Modulated signal definition The modulated signal, at carrier frequency fc, shall be given by:
{}Mtstjftc()Re()exp(())=+20πφ (2) where: - φ0 is an arbitrary phase; - s(t) is the complex envelope of the modulated signal defined as:
stSkgttkKk()()()=−=∑0 (3) where: - K is the maximum number of symbols; - T is the symbol duration; - tk = kT is the symbol time corresponding to modulation symbol S(k); - g(t) is the ideal symbol waveform, obtained by the inverse Fourier transform of a square root raised cosine spectrum G(f), defined as follows: Gf()=1 for Tf2/)1(α−≤ GffT(),(sin(()))=−−051212πα for TfT2/)1(2/)1(αα+≤≤− Gf()=0 for ()Tf2/1α+≥ (4) where α is the roll-off factor, which determines the width of the transmission band at a given symbol rate. The value of α shall be 0,35. For practical implementation, a time limited windowed version of g(t), designed under the constraints given by the specified modulation accuracy and adjacent channel attenuation may be applied. 5.6 Modulation filter definition The modulation filter shall be a linear phase filter which is defined by the magnitude of its frequency response |H(f)| = G(f). SIST EN 300 396-2 V1.2.1:2003

ETSI ETSI EN 300 396-2 V1.2.1 (2002-07) 14 5.7 Modulation block diagram A block diagram of the modulation process is shown on figure 4. This diagram is for explanatory purposes and does not prescribe a specific implementation. The modulation filter excited by the complex Dirac impulse function S(k)δ(t-tk) ideally has an impulse response g(t). B(m)phasetransitiongenerationmodulationsymbolgenerationfrequencytranslationdifferential encodingmodulations(t)M(t)modulationfilterDφ(k)S(k)δ(t-tk) Figure 4: Block diagram of the modulation process 6 Radio transmission and reception
6.1 Introduction This clause defines the requirements for the MS transceiver of the TETRA DMO system. This clause is applicable to TETRA systems operating at radio frequencies of 300 MHz to 1 GHz. 6.2 Frequency bands and channel arrangement DM-MSs may only transmit and receive in those channels allocated for TETRA DMO. Dual Watch Mobile Stations (DW-MSs) and Dual Mode Mobile Stations (DU-MSs) shall also be able to transmit and receive within TETRA Voice plus Data (V+D) channels. The TETRA DM RF carrier separation shall be 25 kHz.
6.3 Reference test planes For the purpose of testing, all DM-MSs shall have at least one antenna connector. Measurements shall be carried out at the ap
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