SIST ETS 300 721 E1:2005

• Abstract:

  Standardization of Mobile Earth Stations in order to limit interference to other services.

• Status: Published
• Publication Date: 31-Jan-2005
• ICS: 33.060.30 - Radio relay and fixed satellite communications systems
• Technical Committee: RES - Radio equipment and systems
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Feb-2005
• Due Date: 01-Feb-2005
• Completion Date: 01-Feb-2005
• Ref Project: ETSI ETS 300 721 ed.1 (1997-06) - Satellite Earth Stations and Systems (SES); Mobile Earth Stations (MES) providing Low Bit Rate Data Communications (LBRDC) using LEO satellites operating below 1 GHz

Overview

SIST ETS 300 721 E1:2005 is a European standard developed by the Slovenski inštitut za standardizacijo (SIST), identical to ETS 300 721 Edition 1 by ETSI. It specifies the requirements for Mobile Earth Stations (MES) that provide Low Bit Rate Data Communications (LBRDC) using Low Earth Orbit (LEO) satellites operating below 1 GHz. The standard’s main objective is to limit radio frequency interference to other radiocommunication and radio astronomy services, ensuring coexistence and operational effectiveness across various communication sectors.

This standard applies to different MES types, including base (BMES), vehicle-mounted (VMES), and portable (PMES) configurations. It details technical requirements for MES operation, emission controls, and control and monitoring functions.

Keywords: Satellite Earth Stations, Mobile Earth Stations, Low Bit Rate Data Communications, LEO satellites, radio frequency interference, MSS, emissions, control functions.

Key Topics

• Scope of Application: Standardization of transmit and receive MES operating under MSS using LEO satellites below 1 GHz, across specific frequency bands, with the goal of interference limitation.
• Frequency Bands: Covers MES transmissions in bands such as 148–150.05 MHz, 235–322 MHz, 335.4–399.9 MHz, and 399.9–400.05 MHz. Includes allocations for both satellite and terrestrial services.
• Emission Limits: Defines strict limits on unwanted emissions both inside and outside assigned bands, protecting existing terrestrial, space, and radio astronomy services.
• Control and Monitoring Functions (CMF): Mandates MES features like processor monitoring, controlled state after power-on, control channel dependency, and reaction to network control commands for transmission enable/disable and identification.
• Testing and Verification: Describes the required tests for verifying emission levels, environmental robustness (including shock and vibration for VMES), and correct operation of CMFs.
• Environmental and Test Conditions: Details the test environment requirements including ambient conditions, wind loading, mechanical shock, vibration, and proper test setups for radiated and conducted emission measurements.

Applications

SIST ETS 300 721 E1:2005 supports a wide range of practical uses in satellite communications by:

• Ensuring Compatibility: Facilitates coexistence between mobile satellite user terminals and other critical services (both terrestrial and space-based) through rigorous emission limits.
• Enabling Mobile Connectivity: Provides a standardized framework for supporting mobile, vehicle-mounted, and portable MES devices that offer reliable low bit rate data services via LEO satellite constellations.
• Protecting Sensitive Services: Includes specific measures for protecting radio astronomy activities from harmful interference by requiring suppression capabilities and rigorous emission control.
• Supporting Industry Compliance: Offers equipment manufacturers clear guidance on control, monitoring, and emission testing obligations, thus supporting easier market entry and regulatory compliance in Europe and internationally.
• Enhancing Reliability: Ensures MES terminals perform correctly in various environmental and operational conditions, including mechanical shocks and vibrations typical in vehicle-mounted or portable scenarios.

Related Standards

For comprehensive compliance and interoperability, the following standards and references are closely connected to SIST ETS 300 721 E1:2005:

• ETSI ETS 300 722: Network Control Facilities for MES providing LBRDC using LEO satellites below 1 GHz (details additional network-side requirements).
• ITU Radio Regulations: Governing frequency allocations and international operation.
• CISPR Publication No 16: Specifications for measuring radio disturbance and immunity.
• ITU-R Recommendations M 1039 and M 1087: Related to modulation techniques and network coordination for interference management in LEO satellite systems.

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By adhering to SIST ETS 300 721 E1:2005, manufacturers and service providers can ensure that Mobile Earth Stations for low bit rate communications over LEO satellite networks operate reliably and with minimal interference, supporting the continued growth of satellite-based data services in a variety of mobile environments.

SLOVENSKI STANDARD
01-februar-2005
Satelitske zemeljske postaje in sistemi (SES) - Mobilne zemeljske postaje (MES), ki
zagotavljajo podatkovne komunikacije z nizkimi bitnimi hitrostmi (LBRDC),
uporabljajo satelite na nizki zemeljski orbiti (LEO) in obratujejo pod 1 GHz
Satellite Earth Stations and Systems (SES); Mobile Earth Stations (MES) providing Low
Bit Rate Data Communications (LBRDC) using LEO satellites operating below 1 GHz
Ta slovenski standard je istoveten z: ETS 300 721 Edition 1
ICS:
33.060.30 Radiorelejni in fiksni satelitski Radio relay and fixed satellite
komunikacijski sistemi communications systems
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN ETS 300 721
TELECOMMUNICATION June 1997
STANDARD
Source: ETSI TC-SES Reference: DE/SES-05017
ICS: 33.020
Key words: Satellite, mobile, earth station, MES, MSS, LEO
Satellite Earth Stations and Systems (SES);
MES providing Low Bit Rate Data Communications (LBRDC)
using LEO satellites operating below 1 GHz
ETSI
European Telecommunications Standards Institute
ETSI Secretariat
Postal address: F-06921 Sophia Antipolis CEDEX - FRANCE
Office address: 650 Route des Lucioles - Sophia Antipolis - Valbonne - FRANCE
X.400: c=fr, a=atlas, p=etsi, s=secretariat - Internet: [e-mail]
Tel.: [phone] - Fax: [phone]
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 1997. All rights reserved.

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ETS 300 721: June 1997
Whilst 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.

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ETS 300 721: June 1997
Contents
Foreword .5
1 Scope .7
2 Normative references.7
3 Definitions and abbreviations .8
3.1 Definitions .8
3.2 Abbreviations .8
4 Test Report.9
5 Radio Frequency (RF).9
5.1 Unwanted emission outside the bands 148 to 150,05 MHz, 235 to 322 MHz, 335,4 to
399,9 MHz and 399,9 to 400,05 MHz .9
5.2 Maximum unwanted emission within the bands 148 to 150,05 MHz, 235 to 322 MHz,
335,4 to 399,9 MHz and 399,9 to 400,05 MHz .11
5.3 Maximum EIRP emission density in the nominated bandwidth .11
5.4 Protection of the radio astronomy service from emissions produced by the MES in the
bands 150,05 to 153 MHz, 322 to 328,6 MHz and 406,1 to 410 MHz .12
6 MES Control and Monitoring Functions (CMFs).12
6.1 Monitoring functions.12
6.1.1 Processor monitoring .12
6.1.2 Transmit frequency generation sub-system .13
6.2 Power-on.13
6.3 Network control reception and authorization.13
6.3.1 Control channel(s) reception .13
6.3.2 Network control commands.14
7 Compliance with RF specifications under conditions of shock and vibration.14
8 NCFs for MES networks.15
Annex A (normative): Environmental and test conditions.16
A.1 Environmental conditions .16
A.2 Test conditions .16
Annex B (normative): Test procedures .17
B.1 Introduction.17
B.2 Equipment Under Test (EUT).17
B.3 Special Test Equipment (STE).17
B.4 Radiated measurement.17
B.4.1 Measuring apparatus .17
B.4.2 Test set-up.18
B.4.3 Measuring procedure.18
B.5 Conducted measurement.18
B.5.1 Measuring apparatus .18
B.5.2 Test set-up.19

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ETS 300 721: June 1997
B.5.3 Measuring procedure .19
History. 20

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ETS 300 721: June 1997
Foreword
This European Telecommunication Standard (ETS) has been produced by the Satellite Earth Stations and
Systems (SES) Technical Committee of the European Telecommunications Standards Institute (ETSI).
Transposition dates
Date of adoption: 20 June 1997
Date of latest announcement of this ETS (doa): 30 September 1997
Date of latest publication of new National Standard
or endorsement of this ETS (dop/e): 31 March 1998
Date of withdrawal of any conflicting National Standard (dow): 31 March 1998

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ETS 300 721: June 1997
Blank page
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ETS 300 721: June 1997
1 Scope
This European Telecommunication Standard (ETS) provides specifications for the standardization of the
characteristics of Mobile Earth Stations (MESs) with both transmit and receive capabilities in order to limit
interference to radiocommunications services.
The Low Earth Orbiting (LEO) satellite networks referred to in this ETS operate under the Mobile Satellite
Service (MSS). The MESs operate as part of a LEO satellite network providing Low Bit Rate Data
Communications (LBRDC).
The frequency bands under which the MESs operate should be within the following bands:
MES MES
Transmit frequencies Receive frequencies
and Service allocations and Service allocations
148 MHz to 149,9 MHz Mobile-Satellite 137 MHz to Mobile-Satellite Service
Service 137,025 MHz
149,9 MHz to 150,05 MHz Land Mobile-Satellite 137,025 MHz to Mobile-Satellite Service
Service 137,175 MHz
235 MHz to 322 MHz Mobile-Satellite 137,175 MHz to Mobile-Satellite Service
Service 137,825 MHz
335,4 MHz to 399,9 MHz Mobile-Satellite 137,825 MHz to Mobile-Satellite Service
Service 138 MHz
399,9 MHz to 400,05 MHz Land Mobile-Satellite 235 MHz to Mobile-Satellite Service
Service 322 MHz
335,4 MHz to Mobile-Satellite Service
399,9 MHz
400,15 MHz to Mobile-Satellite Service
401 MHz
Some LEO satellite networks provide Low Bit Rate Data Communications (LBRDC) using short burst, low
duty cycle MES transmissions in order to reduce interference with existing users. The interference levels
can also be decreased by modulation techniques: Direct Sequence - Spread Spectrum Multiple Access
(DS-SSMA) or Frequency Division Multiple Access (FDMA) using Dynamic Channel Activity Assignment
(DCAA) as described in ITU-R Recommendations M 1039 and M 1087.
These MESs generally have the following characteristics:
- the MESs could be either a Based MES (BMES), a Vehicle mounted MES (VMES) or a Portable
MES (PMES);
- the MES could consist of a number of modules including suitable interfaces to the user.
The main specifications are contained in two categories related to:
- unwanted emissions limitation: to protect terrestrial and space radiocommunications services,
and the radio astronomy services from harmful interference;
- MES control and monitoring functions: to specify a minimum set of Control and Monitoring
Functions (CMFs) to be implemented on each MES in order to minimize the probability that they
originate unwanted transmissions that may give rise to harmful interference to other systems.
2 Normative references
This ETS incorporates, by dated or undated references, provisions from other publications. These
normative references are cited at the appropriate places in the text, and the publications are listed
hereafter. For dated references, subsequent amendments to or revisions of any of these publications
apply to this ETS only when incorporated in it by amendment or revision. For undated references the latest
edition of the publication referred to applies.
[1] ITU Radio Regulations.
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ETS 300 721: June 1997
[2] ETS 300 722: "Satellite Earth Stations and Systems (SES); Network Control Facilities for MES
providing Low Bit Rate Data Communications (LBRDC) using LEO satellites operating below
1 GHz".
[3] CISPR Publication No 16 (1993): "Specification for radio disturbance and immunity measuring
apparatus and methods".
3 Definitions and abbreviations
3.1 Definitions
For the purposes of this ETS, the following definitions apply:
BMES: A MES intended to be installed in a fixed location, and which is powered either by dc or ac mains.
carrier-off state: A MES is in this state when it is not transmitting a signal, i.e. not in the carrier-on state.
carrier-on state: A MES is in this state when it is transmitting a signal in a continuous or non-continuous
mode.
control channel: A Control Channel may be either a command to a particular MES or a signal from the
satellite containing control information to appropriately enable or disable transmissions from a MES.
Internally Mounted Equipment (IME) and Externally Mounted Equipment (EME): The EMEs are the
modules to be externally mounted as stated by the manufacturer or indicated in the user documentation,
the IMEs are the remaining modules intended to be internally mounted Where different specifications
apply to IME and EME, this is noted in the relevant text.
nominated bandwidth: The bandwidth of the MES radio frequency transmission is nominated by the
terminal manufacturer. The nominated bandwidth is wide enough to encompass all spectral elements of
the transmission which have a level greater than the specified unwanted emissions limits. The nominated
bandwidth is wide enough to take account of the transmit carrier frequency stability. The nominated
bandwidth is within the MSS transmit frequency band within which the MES operates.
PMES: A MES intended to be portable , and which is powered by a stand alone battery, and generally
intended to be self-contained and free standing. A PMES would normally consist of a single module, but
may consist of several interconnected modules. In some cases different specifications apply to PMES and
this is noted in the relevant text.
unwanted emissions: Unwanted emissions are those falling outside the nominated bandwidth.
VMES: A MES intended to be installed on a vehicle. A VMES may consist of one or several
interconnected modules as follows:
NOTE: For FDMA / DCAA systems the Nominated Bandwidth does not exceed 25 kHz.
3.2 Abbreviations
For the purposes of this ETS, the following abbreviations apply:
BMES Based MES
CMF Control and Monitoring Function
DCAA Dynamic Channel Activity Assignment
DS-SSMA Direct Sequence Spread Spectrum Multiple Access
EIRP Equivalent Isotropically Radiated Power
EME Externally Mounted Equipment
EUT Equipment Under Test
FDMA Frequency Division Multiple Access
IME Internally Mounted Equipment
MES Mobile Earth Station
MSS Mobile Satellite Service
NCF Network Control Facilities

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ETS 300 721: June 1997
PMES Portable MES
RF Radio Frequency
rms root mean square
STE Special Test Equipment
VMES Vehicle mounted MES
4 Test Report
The test report shall contain:
- the value of the nominated bandwidth, declared by the manufacturer;
- the antenna gain pattern;
- the results of the tests;
- all parameters and operational conditions.
5 Radio Frequency (RF)
Whenever a change of limit between adjacent frequency bands occurs in this subclause, the lower of the
two limits shall apply at the transition frequency.
5.1 Unwanted emission outside the bands 148 to 150,05 MHz, 235 to 322 MHz, 335,4 to
399,9 MHz and 399,9 to 400,05 MHz
Purpose:
Protection of other terrestrial services, space radiocommunications services and the radio astronomy
services from emissions caused by MESs outside the bands 148 to 150,05 MHz, 235 to 322 MHz, 335,4
to 399,9 MHz and 399,9 to 400,05 MHz.
Specification:
With carrier off the MES unwanted emission shall not exceed 33 dBpW, in any 100 kHz.
The unwanted emissions from the MES outside the uplink bands 148 - 150,05 MHz, 235 to 322 MHz,
335,4 to 399,9 MHz and 399,9 to 400,05 MHz, within which the MES is designed to operate, shall not
exceed the limits shown in the following tables.
Table 1: Unwanted emissions outside the operational band 148 to 150,05 MHz
Maximum EIRP density
Frequency (dBpW) Measurement
(MHz) DS-SSMA FDMA bandwidth
0,1 to 146 54 54 100 kHz
146 to 147,5 70 54 100 kHz
147,5 to 148 70 - 105 (note) 54 100 kHz
150,05 to 151,15 70 54 100 kHz
151,15 to 1 000 54 54 100 kHz
1 000 to 12 750 60 60 1 MHz
NOTE: Linearly interpolated in dBpW vs. frequency

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ETS 300 721: June 1997
Table 2: Unwanted emissions outside the operational bands
235 to 322 MHz, 335,5 to 399,9 MHz and 399,9 to 400,05 MHz
Frequency Maximum EIRP density Measuring bandwidth
(MHz) (dBpW)
0,1 to 30 54 100 kHz
30 to 399,9 54 100 kHz
400,05 to 1 000 54 100 kHz
1 000 to 12 750 60 1 MHz
Verification:
By measurement of unwanted emissions generated by an operating MES.
All RF tests in this subclause shall be carried out at ambient environmental conditions of the test
laboratory and for a nominal power supply voltage.
All tests with carrier on shall be undertaken with the transmitter operating at full power and with the
maximum transmit burst rate where applicable.
To enable the performance tests to be carried out, the use of Special Test Equipment (STE), supplied by
the manufacturer, may be necessary. Since this test equipment will be specific for the particular system, it
is not possible to provide detailed specifications in the ETS.
However, the following baseline is provided:
- if the MES requires to receive a modulated carrier from the satellite in order to transmit, then
special test arrangements are required to simulate the satellite signal, thus enabling the MES to
transmit allowing measurement of transmission parameters;
- any specification of these special test arrangements which may have direct or indirect effects on
any requirement or recommendation of this ETS shall be clearly stated by the manufacturer.
Test procedure:
The full system shall be tested according to the test procedure given in annex B.

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