ETSI TS 101 376-1-3 V3.1.1 (2009-07)

ETSI TS 101 376-1-3 V3.1.1 (2009-07)
Technical Specification


GEO-Mobile Radio Interface Specifications (Release 3);
Third Generation Satellite Packet Radio Service;
Part 1: General specifications;
Sub-part 3: General System Description
GMR-1 3G 41.202

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GMR-1 3G 41.202 2 ETSI TS 101 376-1-3 V3.1.1 (2009-07)




Reference
RTS/SES-00309-1-3
Keywords
3G, generic, GMPRS, GMR, GSM, GSO,
interface, MSS, mobile, MES, satellite, radio
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© European Telecommunications Standards Institute 2009.
All rights reserved.

TM TM TM TM
DECT , PLUGTESTS , UMTS , TIPHON , the TIPHON logo and the ETSI logo are Trade Marks of ETSI registered
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TM
3GPP is a Trade Mark of ETSI registered for the benefit of its Members and of the 3GPP Organizational Partners.
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GSM® and the GSM logo are Trade Marks registered and owned by the GSM Association.
ETSI

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GMR-1 3G 41.202 3 ETSI TS 101 376-1-3 V3.1.1 (2009-07)

Contents
Intellectual Property Rights . 4
Foreword . 4
Introduction . 5
1 Scope . 7
2 References . 7
2.1 Normative references . 7
2.2 Informative references . 9
3 Abbreviations . 9
4 Introduction to the GMR-1 3G specifications . 10
4.1 History of the GMR-1 air interface . 10
4.2 Key features of the GMR-1 3G air interface . 12
5 Description of the air interface . 14
5.1 Frame structure . 14
5.2 Channels . 15
5.2.1 Traffic channels . 15
5.2.2 PUI and PRI . 17
5.2.3 Control channels . 17
5.2.3.1 Broadcast Channels . 17
5.2.3.1.1 FCCH or FCCH3 . 17
5.2.3.1.2 GBCH or GBCH3. 18
5.2.3.1.3 BCCH . 18
5.2.3.2 Common Control Channels (CCCH) . 18
5.2.3.2.1 PCH . 18
5.2.3.2.2 RACH or RACH3. 18
5.2.3.2.3 AGCH . 18
5.2.3.2.4 BACH . 18
5.3 FEC . 19
5.4 Modulation . 19
5.5 Power Control and Link Adaptation . 21
5.5.1 General . 21
5.5.2 Link Adaptation . 22
5.5.3 Power Control . 22
5.6 Control channel organization . 22
5.7 MAC/RLC Layer Design . 24
5.8 RRC Layer Design . 26
5.9 PDCP Layer Design . 27
5.10 Terminal types . 28
History . 29

ETSI

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GMR-1 3G 41.202 4 ETSI TS 101 376-1-3 V3.1.1 (2009-07)

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 Technical Specification (TS) has been produced by ETSI Technical Committee Satellite Earth Stations and
Systems (SES).
The contents of the present document are subject to continuing work within TC-SES and may change following formal
TC-SES approval. Should TC-SES modify the contents of the present document it will then be republished by ETSI
with an identifying change of release date and an increase in version number as follows:
Version 3.m.n
where:
• the third digit (n) is incremented when editorial only changes have been incorporated in the specification;
• the second digit (m) is incremented for all other types of changes, i.e. technical enhancements, corrections,
updates, etc.
The present document is part 1, sub-part 3 of a multi-part deliverable covering the GEO-Mobile Radio Interface
Specifications (Release 3) Third Generation Satellite Packet Radio Service, as identified below:
Part 1: "General specifications":
Sub-part 1: "Abbreviations and acronyms";
Sub-part 2: "Introduction to the GMR-1 family";
Sub-part 3: "General System Description";
Part 2: "Service specifications";
Part 3: "Network specifications";
Part 4: "Radio interface protocol specifications";
Part 5: "Radio interface physical layer specifications";
Part 6: "Speech coding specifications";
Part 7: "Terminal adaptor specifications".
ETSI

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GMR-1 3G 41.202 5 ETSI TS 101 376-1-3 V3.1.1 (2009-07)

Introduction
GMR stands for GEO (Geostationary Earth Orbit) Mobile Radio interface, which is used for Mobile Satellite
Services (MSS) utilizing geostationary satellite(s). GMR is derived from the terrestrial digital cellular standard GSM
and supports access to GSM core networks.
The present document is part of the GMR Release 3 specifications. Release 3 specifications are identified in the title
and can also be identified by the version number:
• Release 1 specifications have a GMR 1 prefix in the title and a version number starting with "1" (V1.x.x).
• Release 2 specifications have a GMPRS 1 prefix in the title and a version number starting with "2" (V2.x.x).
• Release 3 specifications have a GMR-1 3G prefix in the title and a version number starting with "3" (V3.x.x).
The GMR release 1 specifications introduce the GEO-Mobile Radio interface specifications for circuit mode Mobile
Satellite Services (MSS) utilizing geostationary satellite(s). GMR release 1 is derived from the terrestrial digital cellular
standard GSM (phase 2) and it supports access to GSM core networks.
The GMR release 2 specifications add packet mode services to GMR release 1. The GMR release 2 specifications
introduce the GEO-Mobile Packet Radio Service (GMPRS). GMPRS is derived from the terrestrial digital cellular
standard GPRS (included in GSM Phase 2+) and it supports access to GSM/GPRS core networks.
The GMR release 3 specifications evolve packet mode services of GMR release 2 to 3rd generation UMTS compatible
services. The GMR release 3 specifications introduce the GEO-Mobile Radio Third Generation (GMR-1 3G) service.
Where applicable, GMR-1 3G is derived from the terrestrial digital cellular standard 3GPP and it supports access to
3GPP core networks.
Due to the differences between terrestrial and satellite channels, some modifications to the GSM or 3GPP standard are
necessary. Some GSM and 3GPP specifications are directly applicable, whereas others are applicable with
modifications. Similarly, some GSM and 3GPP specifications do not apply, while some GMR specifications have no
corresponding GSM or 3GPP specification.
Since GMR is derived from GSM and 3GPP, the organization of the GMR specifications closely follows that of GSM
or 3GPP as appropriate. The GMR numbers have been designed to correspond to the GSM and 3GPP numbering
system. All GMR specifications are allocated a unique GMR number. This GMR number has a different prefix for
Release 2 and Release 3 specifications as follows:
• Release 1: GMR n xx.zyy
• Release 2: GMPRS n xx.zyy
• Release 3: GMR-1 3G xx.zyy
where:
- xx.0yy (z = 0) is used for GMR specifications that have a corresponding GSM or 3GPP specification. In
this case, the numbers xx and yy correspond to the GSM or 3GPP numbering scheme.
- xx.2yy (z = 2) is used for GMR specifications that do not correspond to a GSM or 3GPP specification. In
this case, only the number xx corresponds to the GSM or 3GPP numbering scheme and the number yy is
allocated by GMR.
- n denotes the first (n = 1) or second (n = 2) family of GMR specifications.
ETSI

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GMR-1 3G 41.202 6 ETSI TS 101 376-1-3 V3.1.1 (2009-07)

A GMR system is defined by the combination of a family of GMR specifications and GSM and 3GPP specifications as
follows:
• If a GMR specification exists it takes precedence over the corresponding GSM or 3GPP specification (if any).
This precedence rule applies to any references in the corresponding GSM or 3GPP specifications.
NOTE: Any references to GSM or 3GPP specifications within the GMR specifications are not subject to this
precedence rule. For example, a GMR specification may contain specific references to the corresponding
GSM or 3GPP specification.
• If a GMR specification does not exist, the corresponding GSM or 3GPP specification may or may not apply.
The applicability of the GSM specifications is defined in GMR-1 3G 41.201 [2].
ETSI

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GMR-1 3G 41.202 7 ETSI TS 101 376-1-3 V3.1.1 (2009-07)

1 Scope
The present document is an introduction to Release 3 of the GMR-1 system (GMR-1 3G) and the associated Release 3
of the air interface specification. It is intended to point out some of the differences between the cellular 3GPP and GSM
system and the mobile satellite GMR-1 system.
The GMR-1 system is designed to provide mobile services via a single geostationary satellite as compared to the
thousands of geographically separated cell sites that are used by a typical GSM system. This offers both challenges to
be overcome and opportunities for enhanced services and features.
GMR-1 3G is an extension of the published ETSI TS 101 376 and TIA (S-J-STD-782) specifications for mobile satellite
communications, GMR-1, to support IMT-2000 services. GMR-1 is currently used in mobile satellite systems covering
Europe, Africa, Asia and Middle East. GMR-1 3G is currently being deployed in North America.
2 References
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.
• Non-specific reference may be made only to a complete document or a part thereof and only in the following
cases:
- if it is accepted that it will be possible to use all future changes of the referenced document for the
purposes of the referring document;
- for informative references.
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.
2.1 Normative references
The following referenced documents are indispensable for the application of the present document. For dated
references, only the edition cited applies. For non-specific references, the latest edition of the referenced document
(including any amendments) applies.
[1] GMPRS-1 01.004 (ETSI TS 101 376-1-1): "GEO-Mobile radio Interface Specifications;
Part 1: General specifications; Sub-part 1: Abbreviations and acronyms".
NOTE: This is a reference to a GMR-1 Release 2 specification. See the Introduction for more details.
[2] GMR-1 3G 41.201 (ETSI TS 101 376-1-2): "GEO-Mobile Radio Interface Specifications
(Release 3); Third Generation Satellite Packet Radio Service; Part 1: General specifications;
Sub-part 2: Introduction to the GMR-1 Family".
[3] GMPRS-1 03.003 (ETSI TS 101 376-3-3): "GEO-Mobile Radio Interface Specifications
(Release 2); General Packet Radio Service; Part 3: Network specifications;
Sub-part 3: Numbering, addressing and identification".
NOTE: This is a reference to a GMR-1 Release 2 specification. See the Introduction for more details.
[4] GMR-1 3G 43.022 (ETSI TS 101 376-3-10): "GEO-Mobile Radio Interface Specifications
(Release 3); Third Generation Satellite Packet Radio Service; Part 3: Network specifications;
Sub-part 10: Functions related to Mobile Earth Station (MES) in idle mode".
ETSI

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GMR-1 3G 41.202 8 ETSI TS 101 376-1-3 V3.1.1 (2009-07)

[5] GMR-1 3G 44.008 (ETSI TS 101 376-4-8): "GEO-Mobile Radio Interface Specifications
(Release 3); Third Generation Satellite Packet Radio Service; Part 4: Radio interface protocol
specifications; Sub-part 8: Mobile Radio Interface Layer 3 Specifications".
[6] GMR-1 3G 45.002 (ETSI TS 101 376-5-2): "GEO-Mobile Radio Interface Specifications
(Release 3); Third Generation Satellite Packet Radio Service; Part 5: Radio interface physical layer
specifications; Sub-part 2: Multiplexing and Multiple Access; Stage 2 Service Description".
[7] GMR-1 3G 45.003 (ETSI TS 101 376-5-3): "GEO-Mobile Radio Interface Specifications
(Release 3); Third Generation Satellite Packet Radio Service; Part 5: Radio interface physical layer
specifications; Sub-part 3: Channel Coding".
[8] GMR-1 3G 45.004 (ETSI TS 101 376-5-4): "GEO-Mobile Radio Interface Specifications
(Release 3); Third Generation Satellite Packet Radio Service; Part 5: Radio interface physical layer
specifications; Sub-part 4: Modulation".
[9] GMR-1 3G 45.005 (ETSI TS 101 376-5-5): "GEO-Mobile Radio Interface Specifications
(Release 3); Third Generation Satellite Packet Radio Service; Part 5: Radio interface physical layer
specifications; Sub-part 5: Radio Transmission and Reception".
[10] GMR-1 3G 45.008 (ETSI TS 101 376-5-6): "GEO-Mobile Radio Interface Specifications
(Release 3); Third Generation Satellite Packet Radio Service; Part 5: Radio interface physical layer
specifications; Sub-part 6: Radio Subsystem Link Control".
[11] GMR-1 3G 45.010 (ETSI TS 101 376-5-7): "GEO-Mobile Radio Interface Specifications
(Release 3); Third Generation Satellite Packet Radio Service; Part 5: Radio interface physical layer
specifications; Sub-part 7: Radio Subsystem Synchronization".
[12] GMR-1 3G 44.060 (ETSI TS 101 376-4-12): "GEO-Mobile Radio Interface Specifications
(Release 3); Third Generation Satellite Packet Radio Service; Part 4: Radio interface protocol
specifications; Sub-part 12: Mobile Earth Station (MES) - Base Station System (BSS) interface;
Radio Link Control/ Medium Access Control (RLC/MAC) protocol'.
[13] GMR-1 3G 44.118 (ETSI TS 101 376-4-13): "GEO-Mobile Radio Interface Specifications
(Release 3); Third Generation Satellite Packet Radio Service; Part 4: Radio interface protocol
specifications; Sub-part 13: Radio Resource Control (RRC) protocol; Iu Mode".
[14] 3GPP TS 44.018 (ETSI TS 144 018): "3rd Generation Partnership Project; Digital cellular
telecommunications system (Phase 2+);Mobile radio interface layer 3 specification; Radio
Resource Control (RRC) protocol".
[15] 3GPP TS 44.118 (ETSI TS 144 118): "3rd Generation Partnership Project; Digital cellular
telecommunications system (Phase 2+);Mobile radio interface layer 3 specification, Radio
Resource Control (RRC) protocol; Iu mode".
[16] 3GPP TS 25.323 (ETSI TS 125 323): "3rd Generation Partnership Project; Universal Mobile
Telecommunications System (UMTS);Packet Data Convergence Protocol (PDCP) specification".
[17] GMR-1 3G 44.160: (ETSI TS 101 376-4-14): "GEO-Mobile Radio Interface Specifications
(Release 3); Third Generation Satellite Packet Radio Service; Part 4: Radio interface protocol
specifications; Sub-part 14: Mobile Earth Station (MES) - Base Station System (BSS) interface;
Radio Link Control/Medium Access Control (RLC/MAC) protocol; Iu Mode".
[18] ITU-R Recommendation M.1457-6: "Detailed specifications of the radio interfaces of
International Mobile Telecommunications (IMT-2000)".
ETSI

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GMR-1 3G 41.202 9 ETSI TS 101 376-1-3 V3.1.1 (2009-07)

2.2 Informative references
The following referenced documents are not essential to the use of the present document but they assist the user with
regard to a particular subject area. For non-specific references, the latest version of the referenced document (including
any amendments) applies.
Not applicable.
3 Abbreviations
For the purposes of the present document, the abbreviations given in GMPRS-1 01.004 [1] and the following apply:
APSK Amplitude and Phase Shift Keying
BPSK Binary Phase Shift Keying
DC12 twelve-slot Downlink Control
DCH Dedicated CHannel
DTCH Dedicated Traffic CHannel
EDGE Enhanced Data rates for GSM Evolution
FDD Frequency Division Duplex
GBCH3 GPS Broadcast Channel 3
GERAN GSM EDGE Radio Access Network
GMM/SM GPRS Mobility Management and Session Management
GMPRS-1 GEO-Mobile Packet Radio Service - 1
GMR-1 3G GEO-Mobile Radio interface - 1 Third Generation
GRA GERAN Registration Area
GTP GPRS Tunnelling Protocol
GTP-U GPRS Tunnelling Protocol - User plane
IMS IP Multimedia System
IP Internet Protocol
IPv6 Internet Protocol version 6
Iu Interface between BSS and core network
Iu-PS Interface between BSS and core network - Packet Switched
ksps kilo symbols per second
L1 bis Layer 1 bis
L2 Layer 2
LAPSAT Link Access Protocol for SATellite
LDPC Low Density Parity Check
LLC Logical Link Control
MSS Mobile Satellite Service
MTP-1 Message Transfer Part - 1
MTP-2 Message Transfer Part - 2
MTP-3 Message Transfer Part - 3
NAS Non Access Stratum
Nwk Network
PAPR Peak to Average Power Ratio
PDA Personal Digital Assistant
PDCP Packet Data Convergence Protocol
PDTCH/D Packet Data Traffic Channel/ Downlink
PDTCH/U Packet Data Traffic Channel/ Uplink
PSD Power Spectral Density
QPSK Quaternary Phase Shift Keying
RACH3 Random Access Channel - 3
RR Radio Resource
RRC Radio Resource Control
SBSS Serving Base Station Subsystem
SES Satellite Earth Stations and Systems
TCP Transmission Control Protocol
TDM Time Division Multiplex
UDP User Datagram Protocol
UL UpLink
ETSI

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GMR-1 3G 41.202 10 ETSI TS 101 376-1-3 V3.1.1 (2009-07)

VoIP Voice over Internet Protocol
4 Introduction to the GMR-1 3G specifications
4.1 History of the GMR-1 air interface
The GMR-1 3G air interface is an evolutionary third generation (3G) Mobile Satellite System (MSS) air interface that is
built upon the earlier Release 1 and Release 2 of the GMR-1 air interface.
The GMR-1 development and standardization path follows the evolution of GSM/EDGE Radio Access Network or
GERAN as shown in figure 1.
Circuit switched voice and data
A interface – Nwk side
Version 1.x.x
GSM GMR-1 (2001)
Packet switched data
Gb interface – Nwk side
Version 2.x.x
GPRS r97 GMPRS
144 kbps
Type A terminals
Version 2.1.1
Wideband (2003)
60 kbps
Narrowband (2005)Type C terminals
Version 2.2.1
444 kbps DL/202 kbps UL
Wideband (2008)
Type D terminals
Version 2.3.1
EDGE GMR-1 3G
Packet switched voice and data
Iu interface – Nwk side
Types E to M terminals
S-band and L-band
Version 3.x.x

Figure 1: Evolution of GMR-1 specifications
The GMR-1 air interface specifications were first published in 2001 (GMR-1 Release 1) based on the GSM protocol
architecture with satellite specific optimizations.
The GMR-1 Release 1 radio interface supports compatible services to GSM and reuses the GSM network infrastructure
(see figure 2). It is designed to be used with dual-mode terminals (satellite/terrestrial) allowing the user to roam between
GMR-1 satellite networks and GSM terrestrial networks. Features include spectrally efficient voice, delay tolerant fax,
reliable non-transparent data services up to 9,6 kbps, SMS, cell broadcast services, position-based services, SIM
roaming, high penetration alerting and single-satellite hop terminal-to-terminal calls. A system based on GMR-1
Release 1 is being widely used today in Europe, Africa, Asia and Middle East.
The GMR-1 Release 1 specifications have been revised and updated two additional times in 2002 (Version 1.2.1) and
again in 2005 (Version 1.3.1).
ETSI

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GMR-1 3G 41.202 11 ETSI TS 101 376-1-3 V3.1.1 (2009-07)


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Figure 2: Protocol architecture for control plane (A interface)
In 2003, the GMR-1 air interface was enhanced with the addition of a packet switched data capability and the revised
air interface published as GMR-1 Release 2 or GMPRS-1 (GEO-Mobile Packet Radio System-1). GMPRS-1 provides
IP data services to transportable terminals using GPRS technology with a Gb interface to the core network. Figures 3
and 4 illustrate protocol architecture of the GMPRS-1 air interface for user plane and control plane using Gb interface
towards core network. A number of satellite specific enhancements were introduced at PHY and MAC layers of the
protocol stack to provide improved throughputs and better spectral efficiencies.
AApplppliiccatiatioonn
IPIP IPIP
ReRellaayy
SNSNDDCCPP SNSNDDCCPP GTGTPP GTGTPP
LLCLLC LLLLCC UDUDPP// TTCCPP UDUDPP// TTCCPP
ReRellaayy
RLRLCC BSBSSSGGPP IPIP IPIP
RLRLCC
BSBSSSGGPP
FFrramame e FrFraammee
MAMACC MAMACC L2L2 L2L2
ReRellaayy ReRellaayy
PHPHYY PHPHYY L1L1 b biiss L1L1 b biiss L1L1 L1L1
UUTT 22.55GG SB SBSSSS SSGGSNSN GGGGSNSN
GMGMRR--11

AiAirr GbGb GnGn GiGi
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Figure 3: Protocol architecture for user plane (Gb interface)
ETSI

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GMR-1 3G 41.202 12 ETSI TS 101 376-1-3 V3.1.1 (2009-07)

ReRellaayy
GMGMMM//SSMM GTGTPP
GMGMMM//SSMM
GTGTPP
LLLLCC LLCLLC UDUDPP UDUDPP
ReRellaayy
RLRLCC BSBSSSGGPP IPIP IPIP
RLRLCC BSBSSSGGPP
FrFraammee FrFraammee
MAMACC MAMACC L2L2 L2L2
ReRellaayy ReRellaayy
PHPHYY PHPHYY L1L1 b biiss L1L1 bi biss L1L1 L1L1
MEMESS
SSGGSNSN GGGGSNSN
2.2.55GG S SBBSSSS
GMGMRR--11 A Aiirr

GbGb GGnn
inintteerrffacacee

Figure 4: Protocol architecture for control plane (Gb interface)
GMPRS-1 Version 2.1.1 supports bidirectional packet data rates up to 144 kbps, QoS differentiation across users, and
dynamic link adaptation. GMPRS-1 Version 2.2.1, published in 2005, supports narrow band packet data services to
handheld terminals that permit up to 64 kbps on the forward link (downlink) and 28,8 kbps on the return link (uplink).
GMPRS-1 Version 2.3.1, published in 2008, supports wideband packet services that increase the packet data rates to
444 kbps on the forward link and 202 kbps on the return link for A5 size transportable terminals. The system also
permits data rates up to 400 kbps on the return link with an external antenna. This latest set of specifications uses the
state-of-the art techniques in the physical (PHY) layer such as LDPC codes and 32-APSK modulation and can provide
bi-directional streaming services.
A system using the GMR-1 Release 2 specifications, has been successfully deployed in the field and is being
extensively used in Europe, Africa, Asia and Middle East.
The present document describes the latest enhancement to the GMR-1 air interface specifications. This corresponds to a
new Release 3 of the GMR-1 specifications, also known as GMR-1 3G. GMR-1 3G is based on the adaptation to the
satellite environment of the ETSI TDMA EDGE radio air interface (see ITU-R Recommendation M.1457-6 [18]
TDMA Single-Carrier). GMR-1 3G is therefore the satellite equivalent to EDGE. The protocol architecture is based on
3GPP Release 6, but the air interf
...