ETSI TR 102 884 V1.2.1 (2013-02)

Electromagnetic compatibility and Radio spectrum Matters (ERM); digital Private Mobile Radio (dPMR) General System Design

RTR/ERM-TGDMR-309

General Information

• Status: Published
• Publication Date: 20-Feb-2013
• Technical Committee: ERM TGDMR - Digital Mobile Radio
• Current Stage: 12 - Completion
• Due Date: 05-Mar-2013
• Completion Date: 21-Feb-2013

Standards Content (Sample)

Technical Report
Electromagnetic compatibility
and Radio spectrum Matters (ERM);
digital Private Mobile Radio (dPMR) General System Design

2 ETSI TR 102 884 V1.2.1 (2013-02)

Reference
RTR/ERM-TGDMR-309
Keywords
dPMR, PMR, radio
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ETSI
3 ETSI TR 102 884 V1.2.1 (2013-02)
Contents
Intellectual Property Rights . 6
Foreword . 6
Introduction . 6
1 Scope . 7
1.1 Scope of TS 102 490 . 7
1.2 Scope of TS 102 658 . 7
2 References . 7
2.1 Normative references . 8
2.2 Informative references . 8
3 Definitions, symbols and abbreviations . 9
3.1 Definitions . 9
3.2 Symbols . 11
3.3 Abbreviations . 11
4 Overview of dPMR . 12
4.1 Licence Exempt dPMR . 13
4.2 Licensed dPMR . 13
4.2.1 Licensed dPMR Mode 1 . 13
4.2.2 Licensed dPMR Mode 2 . 13
4.2.3 Licensed dPMR Mode 3 . 14
4.3 Services and Facilities . 14
4.4 Interoperability . 15
4.5 Frequency Considerations . 15
4.5.1 dPMR systems compliant with TS 102 490 . 15
4.5.2 dPMR systems compliant with TS 102 658 . 15
4.5.2.1 6,25 kHz Channel Assignment . 16
4.5.2.2 12,5 kHz Channel Assignment . 16
4.6 Protocol architecture. 16
4.6.1 Architectural Configurations . 16
4.6.1.1 Peer-to-Peer (Licence exempt) . 17
4.6.1.1A Peer-to-Peer Direct Network (Licensed Mode 1) . 17
4.6.1.2 Centralized Repeater Network (Licensed Mode 2) . 18
4.6.1.3 Managed Centralized Repeater Network (Licensed Mode 3) . 18
4.6.1.3.1 Beacon Channel . 18
4.6.1.3.2 Traffic Channel . 18
4.6.1.4 Co-channel BS networks . 19
4.6.2 dPMR services overview . 20
4.6.2.1 Call types . 20
4.6.2.1.1 Parties Involved in the Call . 20
4.7 Channel Codes . 21
4.7.1 Channel Codes for TS 102 490 . 21
4.7.2 Channel Codes for TS 102 658 . 21
4.7.2.1 Channel Code for Mode 1 and Mode 2 Systems . 23
4.7.2.2 Channel Code for Mode 3 Systems . 23
4.7.2.2.1 Channel Code Determined by Frequency . 23
4.7.2.2.2 Channel Code Determined by Frequency and System Identity Code . 23
4.8 Network Identifier (System Identity Code) . 23
4.9 Addressing . 23
4.10 Standard User Interface . 24
4.10.1 The concept of the wildcard character . 25
4.11 Unified Data Transport Mechanism . 25
5 Channel Access Mechanisms . 25
5.1 Random Access (Mode 1, Mode 2) . 25
5.2 Regulated Random Access (Mode 3) . 26
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4 ETSI TR 102 884 V1.2.1 (2013-02)
5.3 Listen Before Transmit (LBT) . 26
5.4 Hang time messages and timers . 26
5.4.1 Definition . 26
5.4.2 Action by receiving stations. 26
5.4.3 Call duration timers . 27
5.5 Transmit admit criteria . 27
5.5.1 General admit criteria . 27
5.5.1.1 ISF admit criteria . 27
5.5.1.2 CSF admit criteria . 27
5.5.1.3 Random Access (Licence exempt, Mode 1, Mode 2) . 27
5.5.1.4 Regulated Random Access (Mode 3) . 28
5.5.1.5 Polling . 28
5.5.1.6 Beacon Signal . 28
5.6 FDMA Structure . 28
5.6.1 Overview of transmission structure . 28
5.6.2 Transmission format . 29
5.6.2.1 Traffic Channel Message Frame . 29
5.6.2.2 Traffic Channel Payload Frame . 29
5.6.2.2.1 Traffic Channel Superframe . 29
5.6.2.2.2 Traffic Channel Packet Data Header Frame . 30
5.6.2.3 Traffic Channel End Frame . 30
5.6.2.4 Beacon SYScast Frame . 30
5.6.2.5 Appended Data Frame . 30
5.6.3 Transmission sequences . 31
5.6.3.1 Traffic Channel Voice or data payload item transmission . 31
5.6.3.2 Traffic Channel Call set up, service request, etc . 31
5.6.3.3 Traffic Channel Acknowledgement: . 31
5.6.3.4 Traffic Channel Status request acknowledgements: . 31
5.6.3.5 Traffic Channel Disconnection: . 32
5.6.3.6 Traffic Channel Preservation Message. 32
5.6.3.7 Mode 3 Beacon Channel . 32
6 Examples of Message Exchange for Calls . 32
6.1 Parties Involved in the Call . 32
6.1.1 Individual call . 32
6.1.2 Group call . 32
6.2 Calls . 33
6.2.1 Mode 1 Call Exchange . 33
6.2.1.1 Mode 1 Voice Call . 33
6.2.1.2 Mode 1 Data Call . 34
6.2.2 Mode 2 Call Exchange . 35
6.2.3 Mode 3 Operation . 36
6.2.4 Packet data . 38
6.2.4.1 Format . 38
6.2.4.2 Standard Packet Exchange Format . 39
7 Synchronization . 41
7.1 Frame synchronization . 41
7.1.1 FS1 . 41
7.1.2 FS2 . 41
7.1.3 FS3 . 41
7.1.4 FS4 . 41
7.2 Synchronization Performance . 41
8 Interleaving and FEC coding . 41
8.1 CRC addition . 42
8.2 Hamming code . 42
8.3 Scrambling . 43
8.4 Interleaving. 43
8.5 FEC coding of CCH (superframe) . 44
8.6 FEC coding of MI (message info') and HI (header info') . 44
8.7 FEC coding of END information . 44
8.8 Channel Coding Process - Example . 44
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5 ETSI TR 102 884 V1.2.1 (2013-02)
8.8.1 Voice superframe . 45
8.8.2 Voice + Attached data call . 45
9 Physical Layer . 47
9.1 General parameters . 47
9.1.1 Frequency range . 47
9.1.2 RF carrier bandwidth . 47
9.1.3 Transmit frequency error . 47
9.1.4 Time base clock drift error . 47
9.2 Modulation . 47
9.2.1 Symbols . 47
9.2.2 4FSK generation . 47
9.2.2.1 Deviation index . 47
9.2.2.2 Square root raised cosine filter . 48
9.2.2.3 4FSK Modulator . 49
9.3 Channel Access Transmitter Ramp Timing and Profile . 49
9.3.1 Transmitter Ramp Timing . 49
9.3.2 Transmit Ramp Profile . 51
Annex A: Guidelines for System Building . 52
A.1 Synchronization patterns and Channel Codes . 52
A.2 Network design and management . 53
A.2.1 General recommendations (for all dPMR modes) . 53
A.2.2 Using network management as a tool (all dPMR modes) . 53
A.2.3 Network management functions (all dPMR modes) . 54
A.2.4 General issues for dPMR mode 3 networks . 54
A.2.5 Network design process . 55
A.2.5.1 Performance analysis . 55
A.2.5.1.1 Grade of service . 55
A.2.5.1.2 Channel hold time . 55
A.2.5.1.3 Performance results . 55
A.2.5.2 Traffic estimate . 56
A.2.6 Network radio environment . 56
A.2.7 Network management . 57
A.2.8 Features . 57
A.3 Power save for dPMR mode 3 systems . 58
A.3.1 Wake up based power save for mode 3 systems . 58
A.3.1.1 Introduction. 58
A.3.1.2 Power Save Mechanism . 59
A.3.1.3 Expected improvement from power save. 61
A.3.1.3.1 Analysis of voice and packet data . 62
A.3.1.3.2 Analysis of short data . 62
A.3.1.3.3 Case study . 63
Annex B: Bibiliography . 64
History . 65

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6 ETSI TR 102 884 V1.2.1 (2013-02)
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://ipr.etsi.org).
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 Technical Report (TR) has been produced by ETSI Technical Committee Electromagnetic compatibility and Radio
spectrum Matters (ERM).
Introduction
The present document has been produced to provide an introduction to dPMR for potential system purchasers, network
operators and service users.
It is in relation to TS 102 490 [i.1] and TS 102 658 [i.2] covering the technical requirements for digital Private Mobile
Radio (dPMR), as identified below:
• TS 102 490 [i.1].
• TS 102 658 [i.2].
It provides an overview, a description of the dPMR services and facilities, technical background and radio aspects,
protocol and service performance, and guidance on numbering and addressing.
It should be understood that, as in all standard setting activities, there is an inherent conflict between the wish to have as
broad a standard as possible and at the same time wanting to have as much of that broad standard available and
implemented right from the beginning. Potential system purchasers, network operators and service users should make
sure they influence the suppliers to have their required functionality available when they need it.
Equipment manufacturers will use the broad flexibility provided within the standard to develop and implement systems
in various ways, and still be conforming according to the standard. This broad availability of systems, each optimized
around certain features and functionalities, needs to be carefully analysed by a network operator and system user to find
the supplier with a system suited best for their needs.
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7 ETSI TR 102 884 V1.2.1 (2013-02)
1 Scope
The present document covers digital Private Mobile Radio (dPMR) equipment using FDMA technology with channel
spacing of 6,25 kHz supporting voice and data applications capable of operating in the existing licensed land mobile
service frequency bands below 1 000 MHz.
The present document includes the baseband signal processing parameters of the Physical Layer (PL) and the protocol
structure at the air interface. The protocol supports different levels of functionality from peer to peer mode to managed
base station access mode: the equipment is based on FDMA with channel spacing of 6,25 kHz supporting voice and
data applications.
dPMR equipment is designed to be compliant with the appropriate harmonized standard for spectrum use,
EN 301 166-2 [i.4].
1.1 Scope of TS 102 490
The present document covers digital private mobile radio equipment operating in peer-to- peer mode only. It covers
only handportable equipment complying with EN 301 166-2 [i.4] and having an integral antenna.
This equipment is for use:
i) In accordance with ECC/DEC/(05)12 [i.7] on harmonized frequencies, technical characteristics, exemption
from individual licensing and free carriage and use of digital PMR446 applications operating in the frequency
band 446,100 MHz to 446,200 MHz.
The equipment conforms to the technical requirements for Digital PMR 446 included in
ECC/DEC/(05)12 [i.7]. This permits operation in the frequency range 446,100 MHz to 446,200 MHz,
maximum e.r.p of 500 mW, and a maximum transmitter time-out-time of 180 seconds.
ii) In the frequency band 149,01875 MHz to 149,11875 MHz under exemption from individual licensing. This
permits a maximum e.r.p of 500 mW, and a maximum transmitter time-out-time of 180 seconds.
1.2 Scope of TS 102 658
The present document supports different levels of functionality from peer to peer mode to managed base station access
mode:
Mode 1 Peer to peer (direct mode) operation without Base Stations or infrastructure.
Mode 2 dPMR systems incorporating one or more Base Stations for repeating or providing system gateways.
Mode 3 dPMR systems operating under a managed access mode in systems incorporating one or more Base
Stations.
All three modes of operation of the present air interface are designed to be compliant with the appropriate harmonized
standard for spectrum use, EN 301 166-2 [i.4]. A polite spectrum access protocol for sharing the physical channel has
also been specified.
2 References
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the
reference document (including any amendments) applies.
Referenced documents which are not found to be publicly available in the expected location might be found at
http://docbox.etsi.org/Reference.
NOTE: While any hyperlinks included in this clause were valid at the time of publication ETSI cannot guarantee
their long term validity.
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8 ETSI TR 102 884 V1.2.1 (2013-02)
2.1 Normative references
The following referenced documents are necessary for the application of the present document.
Not applicable.
2.2 Informative references
The following referenced documents are not necessary for the application of the present document but they assist the
user with regard to a particular subject area.
[i.1] ETSI TS 102 490: "Electromagnetic compatibility and Radio spectrum Matters (ERM); Peer-to-
Peer Digital Private Mobile Radio using FDMA with a channel spacing of 6,25 kHz with e.r.p. of
up to 500 mW".
[i.2] ETSI TS 102 658: "Electromagnetic compatibility and Radio spectrum Matters (ERM); Digital
Private Mobile Radio (dPMR) using FDMA with a channel spacing of 6,25 kHz".
[i.3] IEC EN 61162-1 (2008): "Maritime navigation and radio communications equipment and systems
- Digital Interfaces - Part 1: Single talker and multiple listeners".
[i.4] ETSI EN 301 166-2: "Electromagnetic compatibility and Radio spectrum Matters (ERM); Land
Mobile Service; Radio equipment for analogue and/or digital communication (speech and/or data)
and operating on narrow band channels and having an antenna connector; Part 2: Harmonized EN
covering essential requirements of article 3.2 of the R&TTE Directive".
[i.5] CEPT Recommendation T/R 25-08: "Planning criteria and coordination of frequencies in the Land
Mobile Service in the range 29.7-921 MHz".
[i.6] CEPT ERC Report 25: "The European table of frequency allocations and utilizations covering the
frequency range 9 kHz to 275 GHz".
[i.7] CEPT ECC/DEC/(05)12: "ECC Decision of 28 October 2005 on harmonized frequencies,
technical characteristics, exemption from individual licensing and free carriage and use of digital
PMR 446 applications operating in the frequency band 446,1-446,2 MHz".
[i.8] Draft CEPT ECC Decision (06)06 (WGFM, Cavtat, April 2006): "ECC Decision on the
availability of frequency bands for the introduction of Narrow Band Digital Land Mobile
PMR/PAMR in the 80 MHz, 160 MHz and 400 MHz bands".
[i.9] ETSI TS 102 726-1: "Electromagnetic compatibility and Radio spectrum Matters (ERM);
Conformance testing for Mode 1 of the digital Private Mobile Radio (dPMR); Part 1: Protocol
Implementation Conformance Statement (PICS) proforma".
[i.10] ETSI TS 102 726-2: "Electromagnetic compatibility and Radio spectrum Matters (ERM);
Conformance testing for Mode 1 of the digital Private Mobile Radio (dPMR); Part 2: Test Suite
Structure and Test Purposes (TSS&TP) specification".
[i.11] ETSI TS 102 726-3: "Electromagnetic compatibility and Radio spectrum Matters (ERM);
Conformance testing for Mode 1 of the digital Private Mobile Radio (dPMR); Part 3:
Interoperability Test Suite Structure and Test Purposes (TSS&TP) specification".
[i.12] ETSI TS 102 587-1: "Electromagnetic compatibility and Radio spectrum Matters (ERM); Peer-to-
Peer Digital Private Mobile Radio; Part 1: Conformance testing; Protocol Implementation
Conformance Statement (PICS) proforma".
[i.13] MPT 1318. Engineering Memorandum. Trunked Systems in the. LandMobile Radio Service
February 1986. Revised and reprinted January 1994.
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9 ETSI TR 102 884 V1.2.1 (2013-02)
3 Definitions, symbols and abbreviations
3.1 Definitions
For the purposes of the present document, the following terms and definitions apply:
active_hang_time: time during which a Mode 2 BS preserves the channel for the parties involved in a call
Appended_Data: message carrying principally data that is formatted according to the present document
Base Station (BS): fixed end equipment that is used to obtain dPMR services
beacon channel: channel that carries synchronous beacon frames timed from a BS
bearer service: type of telecommunication service that provides the capability for the information transfer between user
network interfaces, involving only low layer functions (layers 1 to 3 of the OSI model)
NOTE: Confirmed Data and Unconfirmed Data are examples of bearer services.
burst: short duration RF signal that may cause interference to a dPMR transmission item
call: complete sequence of related transactions between MS
NOTE: Transactions may consist of more than one or more item containing specific call related information
Caller Line Identity (CLI): ability to see who is calling you before answering the telephone
call_hang_time: time during which a Mode 1 or Mode 2 channel is available for an emergency pre-emption
complementary service: dPMR service that enables complementary data to be passed between MS and BS as part of
the call set-up phase of another service (such as voice)
Control plane (C-plane): part of the protocol stack dedicated to control and data services
downlink: transmission from BS to MS(s)
extended address: address of an entity that is not a native MS/BS individual/group identity
feature: attribute intrinsic to a station, e.g. MS has an address
intrinsic service: service which is inherent within a voice or data service
item: complete transmission, the conclusion of which the transmission is ended
late entry: where receiving stations that have missed the start of a transmission are able to recover all information about
the call from subsequent message frames
line connected: call whereby one end of the call is connected to the radio system that does not use the DMR Air
Interface
NOTE: Examples may be connection to the PSTN or a PABX.
logical channel: distinct data path between logical endpoints
Manufacturers ID (MID): 8 bit identifier assigned to a particular manufacturer
Mobile Station (MS): physical grouping that contains all of the mobile equipment that is used to obtain dPMR mobile
services
mode: class of operation of a dPMR system
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10 ETSI TR 102 884 V1.2.1 (2013-02)
multi-part call set-up: call set-up procedure whereby the full information to be exchanged between entities cannot be
accommodated in a single message frame
NOTE: The UDT procedure is invoked to transfer the address information using UDT signalling. UDT is also
invoked to transport complementary and user data between dPMR entities.
network personalization: configuration parameters appropriate to network configuration programmed into an MS that
may be set by an external agency but not by the user of an MS
payload: part of a data stream representing the user information
peer-to-peer mode: mode of operation where MS may communicate outside the control of a network
NOTE: This is communication technique where any MS may communicate with one or more other MS(s) without
the need for any additional equipment (e.g. BS).
personalization: address and configuration information that characterizes a particular dPMR MS
NOTE: This information may be implanted by the installer before putting an MS into service.
physical channel: FDMA transmission
polite protocol: Listen Before Transmit (LBT) protocol
NOTE: This is a medium access protocol that implements a LBT function in order to ensure that the channel is
free before transmitting.
prefix: most significant digit of an MS address in the user domain
radio frequency channel: radio frequency carrier (RF carrier)
NOTE: This is a specified portion of the RF spectrum. The RF carrier separation is 6,25 kHz.
Received Signal Strength Indication (RSSI): root mean squared value of the signal received at the receiver antenna
signalling: exchange of information specifically concerned with the establishment and control of connections, and with
management, in a telecommunication network
simplex: mode of working by which information can be transferred in both directions but not at the same time
NOTE: Simplex is also known as half duplex.
superframe: four concatenated FDMA frames
NOTE: A superframe has a length of 320 ms.
supplementary service: supplementary service modifies or supplements a tele-service or bearer service
NOTE: Consequently, it cannot be offered to a user as a standalone service. It is offered together with or in
association with a tele-service or bearer service. The same supplementary service may be common to a
number of telecommunication services. Late entry is an example of supplementary service.
talkgroup: collection of MSs that have the same group address
traffic channel: channel in which control/payload frames are exchanged asynchronously
uplink: transmission from MS to BS
user numbering: decimal representation of dPMR air interface addresses, as seen by the user, i.e. user visible
numbering
telecommunication service: offered by a dPMR entity in order to satisfy a specific telecommunication requirement
tele-service: type of telecommunication service that provides the complete capability, including terminal equipment
functions, for communication between users
NOTE: Individual voice calls and talkgroup voice calls are examples of tele-services.
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11 ETSI TR 102 884 V1.2.1 (2013-02)
User-plane (U-plane): part of the protocol stack dedicated to user voice services
vocoder socket: 216 bits vocoder payload
wildcard: character in the user domain that represents all digits 0 to 9
3.2 Symbols
For the purposes of the present document, the following symbols apply:
B algorithm that converts MS dialable talkgroup addresses between the User Interface and the Air
Interface
dBm absolute power level relative to 1 mW, expressed in dB
dBp Power relative to the average power transmitted during a transmitted item in dB
Hz frequency
Eb Energy per bit
ms milli-seconds
No Noise per Hz
ppm parts per million
3.3 Abbreviations
For the purposes of the present document, the following abbreviations apply:
4FSK Four-level Frequency Shift Keying
ACK ACKnowledgment
AI Air Interface
BCD Binary Coded Decimal
BS Base Station
CC Channel Code
CCH Control CHannel
CLI Caller Line Identity
COCHIn CO-CHannel Identity n (n = 1 to 15)
C-plane Control-plane
CRC Cyclic Redundancy Checksum
NOTE: For data error detection.
CSF Configured Services and Facilities
dPMR digital Private Mobile Radio
e.r.p effective radiated power
FDMA Frequency Division Multiple Access
FEC Forward Error Correction
FN Frame Numbering
GPS Global Positioning System
HI Header Information
ID Identifier
IP Internet Protocol
IPV Internet Protocol Version
ISF Initial Services and Facilities
IT Information Technology
LBT Listen Before Transmit
MI Message Information
MID Manufacturers ID
MMI Man Machine Interface
MS Mobile Station
MSs Multiplicity of mobile or handportable Stations
NACK Negative ACKnowledgment
OACSU Off Air Call Set Up
PABX Private Automatic Branch eXchange
PC Personal Computer
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12 ETSI TR 102 884 V1.2.1 (2013-02)
PDF Packet Data Format
PDU Protocol Data Unit
PL Physical Layer
PMR Private Mobile Radio
PSTN Public Switched Telephone Network
PTT Push-To-Talk
RF Radio Frequency
RSSI Received Signal Strength Indication
SLD SLow Data
SYNC SYNChronization
TCH Traffic CHannel
UDT Unified Data Transport
U-plane User-plane
4 Overview of dPMR
The digital Private Mobile Radio (dPMR) protocol employs a Frequency Division Multiple Access (FDMA) technology
in an RF carrier bandwidth of 6,25 kHz.
There are two types of dPMR equipment.
• TS 102 490 [i.1] describes low-cost peer to peer terminals in licence exempt spectrum.
• TS 102 658 [i.2] describes terminals and base station equipment for the professional market offering both
peer-to-peer and repeater operation.
Business and industry users have a basic need for flexible, efficient and cost effective communications systems and this
was the fundamental reason for the development of the dPMR standards.
In technical terms these requirements can be all met by using a low-latency, dPMR protocol employing a suitable
quality vocoder. The coding gain is used to recover good quality audio at the coverage boundary rather than to extend
the range to distances not achievable by analogue systems at the same transmit power.
dPMR is intended to be an
...