ETSI TR 103 704 V1.1.1 (2022-05)

Urban Rail ITS and Road ITS applications in the 5,9 GHz band; Measurement campaign to confirm simulation parameters to define Urban Rail ITS protected zones in 5 915 MHz to 5 925 MHz

DTR/RT-JTFIR-4

General Information

• Status: Not Published
• Technical Committee: RT JTFIR - Joint Task Force ITS RT
• Current Stage: 12 - Completion
• Due Date: 30-May-2022
• Completion Date: 30-May-2022

Standards Content (Sample)

TECHNICAL REPORT
Urban Rail ITS and Road ITS applications in the 5,9 GHz band;
Measurement campaign to confirm simulation parameters
to define Urban Rail ITS protected zones
in 5 915 MHz to 5 925 MHz
2 ETSI TR 103 704 V1.1.1 (2022-05)

Reference
DTR/RT-JTFIR-4
Keywords
ITS, simulation, spectrum
ETSI
650 Route des Lucioles
F-06921 Sophia Antipolis Cedex - FRANCE

Tel.: [phone]  Fax: [phone]

Siret N° 348 623 562 00017 - APE 7112B
Association à but non lucratif enregistrée à la
Sous-Préfecture de Grasse (06) N° w061004871

Important notice
The present document can be downloaded from:
http://www.etsi.org/standards-search
The present document may be made available in electronic versions and/or in print. The content of any electronic and/or
print versions of the present document shall not be modified without the prior written authorization of ETSI. In case of any
existing or perceived difference in contents between such versions and/or in print, the prevailing version of an ETSI
deliverable is the one made publicly available in PDF format at www.etsi.org/deliver.
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
https://portal.etsi.org/TB/ETSIDeliverableStatus.aspx
If you find errors in the present document, please send your comment to one of the following services:
https://portal.etsi.org/People/CommiteeSupportStaff.aspx
If you find a security vulnerability in the present document, please report it through our
Coordinated Vulnerability Disclosure Program:
https://www.etsi.org/standards/coordinated-vulnerability-disclosure
Notice of disclaimer & limitation of liability
The information provided in the present deliverable is directed solely to professionals who have the appropriate degree of
experience to understand and interpret its content in accordance with generally accepted engineering or
other professional standard and applicable regulations.
No recommendation as to products and services or vendors is made or should be implied.
No representation or warranty is made that this deliverable is technically accurate or sufficient or conforms to any law
rule and/or regulation and further, no representation or warranty is made of merchantability or fitness
and/or governmental
for any particular purpose or against infringement of intellectual property rights.
In no event shall ETSI be held liable for loss of profits or any other incidental or consequential damages.

Any software contained in this deliverable is provided "AS IS" with no warranties, express or implied, including but not
limited to, the warranties of merchantability, fitness for a particular purpose and non-infringement of intellectual property
rights and ETSI shall not be held liable in any event for any damages whatsoever (including, without limitation, damages
for loss of profits, business interruption, loss of information, or any other pecuniary loss) arising out of or related to the use
of or inability to use the software.
Copyright Notification
No part may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and
microfilm except as authorized by written permission of ETSI.
The content of the PDF version shall not be modified without the written authorization of ETSI.
The copyright and the foregoing restriction extend to reproduction in all media.

© ETSI 2022.
All rights reserved.
ETSI
3 ETSI TR 103 704 V1.1.1 (2022-05)
Contents
Intellectual Property Rights . 6
Foreword . 6
Modal verbs terminology . 6
Executive summary . 6
Introduction . 7
1 Scope . 8
2 References . 8
2.1 Normative references . 8
2.2 Informative references . 8
3 Definition of terms, symbols and abbreviations . 9
3.1 Terms . 9
3.2 Symbols . 9
3.3 Abbreviations . 9
4 Measurement campaign context and organization . 10
4.1 General . 10
4.2 Available results and studies . 11
5 Critical interference scenarios . 12
5.1 Description of critical interference scenarios . 12
5.1.1 Introduction. 12
5.1.2 Road parallel to Urban Rail tracks . 12
5.1.3 Road crossing Rail tracks . 14
5.1.4 Isles (group of vehicles) in a city or multiple RF sources . 15
5.2 Summary . 15
6 Identification of the relevant areas to conduct the measurements . 16
6.1 Overview . 16
6.2 List of Identified relevant areas to conduct measurements . 16
6.3 Description of each selected relevant areas . 17
6.3.1 Selected relevant areas of RATP Line 6 . 17
6.3.1.0 Description of the sections of RATP Line 6 . 17
6.3.1.1 Description of the section 1 of RATP Line 6 . 17
6.3.1.2 Description of the section 2 of RATP Line 6 . 18
6.3.1.3 Description of the section 3 of RATP Line 6 . 19
6.3.2 Selected relevant areas of RATP Line 8 . 21
6.3.2.1 Description of the sections of RATP Line 8 . 21
6.3.2.2 Description of the section 1 of RATP Line 8 . 21
6.3.2.3 Description of the section 2 of RATP Line 8 . 22
6.3.2.4 Description of the section 3 of RATP Line 8 . 23
6.4 Specific requirements to conduct the measurements . 24
7 Description of measurement procedures and measurement tools for each case . 25
7.1 Overview . 25
7.2 General test set-up . 25
7.2.1 High level description of the test set-up. 25
7.2.2 Requirements for the RF measurement tool . 26
7.3 Description of test set-up and RF measurement tool . 28
7.4 Measurement procedures . 31
7.5 Implementation of the Measurements campaign . 33
7.5.1 Implementation process . 33
7.5.2 Definition of Planning for measurements . 33
7.5.3 Preparation of the RF measurements tools . 34
7.5.3.1 Preparation of the RF measurements tool for vehicles . 34
7.5.3.2 Preparation of the RF measurements tool for train . 34
ETSI
4 ETSI TR 103 704 V1.1.1 (2022-05)
7.5.3.3 Preparation of the RF measurements tool for the base stations . 34
7.5.4 Measurement set-up as implemented and onsite parameters . 35
8 Measurement results analysis . 37
8.1 Method of analysis . 37
8.1.1 General approach . 37
8.1.2 Reference interfaces . 38
8.2 Presentation of results per relevant area . 38
8.2.1 Mode of presentation . 38
8.2.2 Analysis of measurements for Line 6 . 39
8.2.2.1 Analysis of measurements for the section 1 of Line 6 . 39
8.2.2.1.1 Localization of the receivers for section 1 of Line 6 . 39
8.2.2.1.2 Analysis of measurements for each receiver of section 1 . 40
8.2.2.1.3 Summary of observation for the section 1 of Line 6 . 46
8.2.2.2 Analysis of measurements for the section 2 of Line 6 . 46
8.2.2.2.1 Localization of the receivers for section 2 of Line 6 . 46
8.2.2.2.2 Analysis of measurements for each receiver of section 2 . 48
8.2.2.2.3 Measurements with train in the tunnel . 51
8.2.2.2.4 Summary of observation for the section 2 of Line 6 . 56
8.2.2.3 Analysis of measurements for the section 3 of Line 6 . 56
8.2.2.3.1 Localization of the receivers for section 3 of Line 6 . 56
8.2.2.3.2 Analysis of measurements for each receiver of section 3 . 57
8.2.2.3.3 Summary of observation for the section 2 of Line 6 . 62
8.2.3 Analysis of measurements for Line 8 . 63
8.2.3.1 Analysis of the Measurements for the section 1 of Line 8 . 63
8.2.3.1.1 Localization of the receivers for section 1 of Line 8 . 63
8.2.3.1.2 Analysis of measurements for each receiver of section 1 . 64
8.2.3.1.3 Summary L8 section 1 . 68
8.2.3.2 Analysis of measurements for the section 2 of Line 8 . 68
8.2.3.2.1 Localization of the receivers for section 2 of Line 8 . 68
8.2.3.2.2 Analysis of measurements for each receiver of section 2 . 71
8.2.3.2.3 Summary L8 section 2-3. 84
8.2.4 Measurement results summary . 84
8.3 Detailed analysis for some scenarios . 85
8.3.1 Detailed measurements on parallel roads and perpendicular roads . 85
8.3.1.1 Description of the scenarios . 85
8.3.1.2 Description of data processing method . 85
8.3.1.3 Selected Scenarios for Line 8 - Suburban environment . 86
8.3.1.3.0 Introduction . 86
8.3.1.3.1 Train rear cab at position 1 on Line 8 section 2-3 . 86
8.3.1.3.2 Train front cab at position 3 on Line 8 section 2-3 measurements with vehicle 1 . 87
8.3.1.3.3 Train front cab at position 3 on Line 8 section 2-3 measurements with vehicle 2 . 88
8.3.1.3.4 Train front cab at position 4 on Line 8 section 2-3 . 88
8.3.1.3.5 Base station at position 1 on Line 8 section 2-3 . 89
8.3.1.3.6 Base station at position 3 on Line 8 section 2-3 . 90
8.3.1.4 Selected Scenarios for Line 6 - Urban environment . 91
8.3.1.4.0 Introduction . 91
8.3.1.4.1 Base station configured as train at position 1 on Line 6 section 1 . 91
8.3.1.4.2 Base station configured as train at position 3 on Line 6 section 1 . 92
8.3.1.4.3 Base station configured as train at position 2 on Line 6 section 2 measurements with vehicle
1 . 93
8.3.1.4.4 Base station configured as train at position 2 on Line 6 section 1 measurement with vehicle
2 . 94
8.3.1.4.5 Base station configured as train at position 2 on Line 6 section 2 focus on perpendicular
road . 95
8.3.1.4.6 Base station at position 2 on Line 6 section 2. 96
8.3.1.4.7 Base station at position 1 on Line 6 section 2. 97
8.3.1.5 Selected Scenarios for Line 6 section 3 - Bercy Bridge . 98
8.3.1.5.0 Introduction . 98
8.3.1.5.1 Base station configured as train at position 1 on Line 6 section 3 (Bercy Bridge)
measurements with vehicle 1 . 98
ETSI
5 ETSI TR 103 704 V1.1.1 (2022-05)
8.3.1.5.2 Base station configured as train at position 1 on Line 6 section 3 (Bercy Bridge)
measurements with vehicle 2 . 99
8.3.1.5.3 Base station at position 2 on Line 6 section 3 (Bercy bridge) . 100
8.3.1.5.4 Base station at position 2 on Line 6 section 3 (Bercy bridge) . 101
8.3.1.6 Overall received levels versus distance . 102
8.3.2 Effect of antenna directivity. 105
8.4 Comparison of measurements with simulations for some base stations and trains . 107
8.4.1 Propagation simulator . 107
8.4.2 Analysis of the results of comparison . 108
8.4.3 Points simulated all along the tracks . 115
8.4.4 Comparison between 3,2 m and 2,5 m vehicles antenna heights . 116
8.4.5 Summary of the comparison between the measurements and simulations . 118
8.5 Statistical analysis . 118
8.5.1 Ranges of levels received from vehicles . 118
8.5.2 Comparison between the two vehicles' antenna heights . 126
8.5.3 Comparison between base stations and train receivers . 129
8.5.4 Summary of statistical analysis . 130
9 Conclusion and proposal . 130
Annex A: List of test equipment . 132
A.1 Detailed description of the RF measurement tool . 132
A.2 Antenna for CBTC Base station and train . 132
A.3 Choice vehicle roof-top antenna for measurements . 133
A.3.1 Introduction . 133
A.3.2 Choice of Antenna . 136
A.3.3 Choice of Antenna height above the roof . 137
A.4 Antenna reference measurements . 140
A.4.1 Introduction . 140
A.4.2 Scope of the measurements . 140
A.4.3 Measurement setup . 141
A.4.4 Conclusion . 149
A.4.5 List of equipment used in the measurements . 149
A.5 GNSS . 149
A.5.1 Introduction . 149
A.5.1.1 Scope . 149
A.5.1.2 Document Structure . 149
A.5.1.3 Background . 149
A.5.2 GNSS Overview . 150
A.5.2.1 Definitions . 150
A.5.2.2 Type of correction for high accuracy positioning . 150
A.5.3 Implementation . 151
A.5.3.1 Equipment . 151
Annex B: Simple Urban rail and Suburban rail propagation models . 157
Annex C: Desensitization maps . 158
C.1 Introduction . 158
C.2 Desensitization maps for Line 6 . 159
C.3 Desensitization maps for Line 8 . 164
Annex D: Description of the propagation simulator tool . 173
Annex E: Reading the box plots. 175
Annex F: Bibliography . 176
History . 177
ETSI
6 ETSI TR 103 704 V1.1.1 (2022-05)
Intellectual Property Rights
Essential patents
IPRs essential or potentially essential to normative deliverables may have been declared to ETSI. The declarations
pertaining to these essential IPRs, if any, are 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 (https://ipr.etsi.org/).
Pursuant to the ETSI Directives including the ETSI IPR Policy, no investigation regarding the essentiality of IPRs,
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.
Trademarks
The present document may include trademarks and/or tradenames which are asserted and/or registered by their owners.
ETSI claims no ownership of these except for any which are indicated as being the property of ETSI, and conveys no
right to use or reproduce any trademark and/or tradename. Mention of those trademarks in the present document does
not constitute an endorsement by ETSI of products, services or organizations associated with those trademarks.
DECT™, PLUGTESTS™, UMTS™ and the ETSI logo are trademarks of ETSI registered for the benefit of its

Members. 3GPP™ and LTE™ are trademarks of ETSI registered for the benefit of its Members and of the 3GPP
Organizational Partners. oneM2M™ logo is a trademark of ETSI registered for the benefit of its Members and of the ®
oneM2M Partners. GSM and the GSM logo are trademarks registered and owned by the GSM Association.
Copyright acknowledgment
© OpenStreetMap contributors - www.openstreetmap.org/copyright.
Foreword
This Technical Report (TR) has been produced by ETSI Technical Committee Railway Telecommunications (RT).
Modal verbs terminology
In the present document "should", "should not", "may", "need not", "will", "will not", "can" and "cannot" are to be
interpreted as described in clause 3.2 of the ETSI Drafting Rules (Verbal forms for the expression of provisions).
"must" and "must not" are NOT allowed in ETSI deliverables except when used in direct citation.
Executive summary
ETSI TR 103 580 [i.2] described possible sharing and interference mitigation techniques between Road ITS and Urban
Rail ITS. These techniques would allow the technical implementation of the regulatory priority regime afforded to
Urban Rail ITS in the spectrum band 5 915 MHz to 5 925 MHz.
ETSI TR 103 580 [i.2] concluded that a measurement campaign would be needed to validate the results and the
simulations parameters applicable for the definition of the protected zones, where mitigation techniques would be
required.
The present document describes the work undertaken to perform the required measurements and analyses the resulting
data. The following items are covered:
• Identification of relevant test cases representative of typical coexistence situations.
ETSI
7 ETSI TR 103 704 V1.1.1 (2022-05)
• Identification of relevant areas to conduct the measurements.
• Description of test procedures and test tools.
• Detailed plan of the measurements.
• Analysis of the measurements campaign.
• Conclusion on the results.
The analysis confirms that the levels received by urban rail ITS, from vehicles transmitting with the maximum allowed
output power of 33 dBm/10 MHz EIRP and driving in the surrounding of a metro Line, are above the defined protection
levels of the CBTC communications.
Although the received levels in the present document are displayed for vehicles transmitting at maximum output power
(23 dBm/MHz, i.e. 33 dBm per a 10 MHz channel as defined in Commission Implementing Decision (EU)
2020/1426 [i.8]), the results could be scaled down for different transmit powers (e.g. 10 dB decrease for vehicles
transmitting 23 dBm/10 MHz).
The aggregated power from multiple vehicles interfering has not been investigated in the present document, however
this could be investigated later with the measurement data available.
The assessment of interference on CBTC systems is outside the scope of the present document. Following the
measurement campaign presented in the present document, a revision of ETSI TR 103 580 [i.2] will be required. The
revision will focus on identifying the most appropriate mitigation technique. This will be the basis of future normative
work allowing sharing of the spectrum band 5 915 MHz to 5 925 MHz between Urban Rail and Road ITS.
Introduction
Commission Implementing Decision (EU) 2020/1426 [i.8] designates the band 5 875-5 935 MHz for intelligent
transport systems and limits it to urban rail ITS in 5 925 to 5 935MHz. [i.8] also states that "Road ITS applications shall
have priority below 5 915 MHz and urban rail ITS applications shall have priority above 5 915 MHz, so that protection
is afforded to the application having priority" and further instructs that "Access by road ITS to the frequency range
5 915-5 925 MHz shall be limited to applications involving infrastructure-to-vehicle (I2V) connectivity only,
coordinated, where appropriate, with urban rail ITS"
The sharing and interference mitigation techniques would enable the technical implementation of the priority regime
afforded to Urban Rail ITS.
One key concept introduced in ETSI TR 103 580 [i.2] is the "Urban rail protected zones" which should be used to
define the mitigation areas to protect Urban Rail communications. ETSI TR 103 580 [i.2] concluded that a measurement
campaign would be needed to validate the results and the simulation parameters applicable for the definition of the
protected zones.
In the present document, a set of measurement scenarios are defined together with a set of relevant areas, on two metro
Lines, where measurements have been performed. The measurement setup, procedures and planning are also
introduced. After completion of the measurement campaign, the measurements have been analysed and the results of
these analysis are presented.
The measurements performed on the three sections of RATP Line 6 and on the 3 sections of RATP Line 8, both in
Paris, with trains and base stations, confirm the levels received by trains and base stations from vehicles transmitting
with the maximum allowed output power of 33 dBm/10 MHz EIRP and driving on parallel roads, on bridge above or
below the tracks and in different areas in the surrounding of a metro Line are above the defined protection levels of the
CBTC communications. This result could be hypothesized already from the simulations of propagation performed
previously and aiming at identifying the relevant areas.

ETSI
8 ETSI TR 103 704 V1.1.1 (2022-05)
1 Scope
The present document describes the work undertaken to perform the required measurements, and analyses the resulting
data. The following items are covered:
• Identification of relevant test cases representative of typical coexistence situations.
• Identification of relevant areas to conduct the measurements.
• Description of test procedures and test tools.
• Detailed plan of the measurements.
• Analysis of the measurements campaign.
• Conclusion on the results.
2 References
2.1 Normative references
Normative references are not applicable in the present document.
2.2 Informative 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
referenced document (including any amendments) applies.
NOTE: While any hyperlinks included in this clause were valid at the time of publication ETSI cannot guarantee
their long-term validity.
The following referenced documents are not necessary for the application of the present document, but they assist the
user regarding a particular subject area.
[i.1] Commission Decision 2008/671/EC on the harmonised use of radio spectrum in the 5875 -
5905 MHz frequency band for safety related applications of Intelligent Transport Systems (ITS).
[i.2] ETSI TR 103 580 (V1.1.1) (2019-08): "Urban Rail ITS and Road ITS applications in the 5,9 GHz
band; Investigations for the shared use of spectrum".
[i.3] ETSI EN 302 571 (V2.1.1): "Intelligent Transport Systems (ITS); Radiocommunications
equipment operating in the 5 855 MHz to 5 925 MHz frequency band; Harmonised Standard
covering the essential requirements of article 3.2 of Directive 2014/53/EU".
[i.4] ECC Report 101: "Compatibility studies in the band 5855 - 5 925 MHz between Intelligent
Transports Systems (ITS) and other systems".
[i.5] ECC Report 68:"Compatibility studies in the band 5725-5875 MHz between Fixed Wireless
Access (FWA) systems and other systems", Riga, June 2005.
[i.6] CEPT Report 71: "Report from CEPT to the European Commission in response to the Mandate to
study the extension of the Intelligent Transport Systems (ITS) safety-related band at 5.9 GHz".
[i.7] Recommendation ITU-R P.1411-6: "Propagation data and prediction methods for the planning of
short-range outdoor radiocommunication systems and radio local area networks in the frequency
range 300 MHz to 100 GHz".
ETSI
9 ETSI TR 103 704 V1.1.1 (2022-05)
[i.8] Commission Implementing Decision (EU) 2020/1426 of 7 October 2020 on the harmonised use of
radio spectrum in the 5 875-5 935 MHz frequency band for safety-related applications of
intelligent transport systems (ITS) and repealing Decision 2008/671/EC.
[i.9] Z. Živković, D. Senić, C. Bodendorf, J. Skrzypczynski and A. Šarolić: "Radiation pattern and
impedance of a quarter wavelength monopole antenna above a finite ground plane", SoftCOM
2012, 20th International Conference on Software, Telecommunications and Computer Networks,
2012, pp. 1-5.
[i.10] A. Kwoczek, Z. Raida, J. Láčík, M. Pokorny, J. Puskelý and P. Vágner: "Influence of car
panorama glass roofs on Car2Car communication (poster)", 2011 IEEE Vehicular Networking
Conference (VNC), 2011, pp. 246-251, doi: 10.1109/VNC.2011.6117107.
[i.11] IEEE 802.11p™: "IEEE Standard for Information technology-- Local and metropolitan area
networks-- Specific requirements-- Part 11: Wireless LAN Medium Access Control (MAC) and
Physical Layer (PHY) Specifications Amendment 6: Wireless Access in Vehicular Environments".
[i.12] Ublox receiver ZED F9R Product sheet.
[i.13] Recommendation ITU-R F.1336:"Reference radiation patterns of omni-directional, sector and
other antennas in point-to-multipoint systems for use in sharing studies in the frequency range
from 1 GHz to about 70 GHz".
[i.14] HTZ Communications - brochure.
NOTE: Available at https://atdi.com/products-and-solutions/htz-communications.
3 Definition of terms, symbols and abbreviations
3.1 Terms
Void.
3.2 Symbols
Void.
3.3 Abbreviations
For the purposes of the present document, the following abbreviations apply:
ADR Automotive Dead Reckoning
BS Base Station
C/I Carrier to Interference ratio
CBTC Communications-Based Train Control systems
CEPT European Conference of Postal and Telecommunications Administrations
dB Decibel
dBi Decibel isotropic
dBm decibel-milliwatts
DCC Decentralized Congestion Control
DHCP Dynamic Host Configuration Protocol
DNS Domain Name Server
DSRC Dedicated Short-Range Communications
EC European Commission
ECC Electronic Communications Committee
EIRP Equivalent Isotopically Radiated Power
EMSL European Microwave Signature Laboratory
ETSI European Telecommunications Standards Institute
ETSI
10 ETSI TR 103 704 V1.1.1 (2022-05)
EU European Union
GNSS Global Navigation Satellite System
GPS Global Positioning System
HTTP HyperText Transfer Protocol
I2V Infrastructure to-Vehicle
IMU Inertial Measurement Unit
IP Internet Protocol
ITS Intelligent Transport Systems
ITS-G5 Intelligent Transport Systems operating in the 5 GHz frequency band
JRC DG Joint Research Centre of EC
LoS Line-of-Sight
LTE Long Term Evolution
NA Non Applicable
NLoS Non-Line of Sight
NRTK Network Real Time Kinematic
NTRIP Network Transport of RTCM via Internet Protocol
OBU Onboard Unit
OCC Operation Control Centre
OEM Original Equipment Manufacturer
NOTE: A term in the automotive industry used for the vehicle manufacturers.
OSR Observation Space Representation
QPSK Quadrature Phase-Shift Keying
QZSS Quasi-Zenith Satellite System
RATP Régie Autonome des Transports Parisiens
NOTE: State-owned public transport operator and maintainer Metro of Paris.
RF Radio Frequency
RSSI Received Signal Strength Indicator
RTCM Radio Technical Commission for Maritime
RTK Real Time Kinematic
Rx Receiver
SBAS Satellite-Based Augmentation System
SUV Sports Utility Vehicle
TR Technical Report
Tx Transmitter
V2V Vehicle to Vehicle
V2X Vehicle to anything communication
VPN Virtual Private Network
WGS 84 World Geodetic System 1984
4 Measurement campaign context and organization
4.1 General
In October 2017, the European Commission mandated CEPT/ECC to provide the Commission with the necessary
information to consider the amendment of Commission Decision 2008/671/EC [i.1] of 5 August 2008, on the
harmonised use of radio spectrum in the 5 875 MHz to 5 905 MHz frequency band for safety-related applications of
Intelligent Transport Systems (ITS).
In particular, the purpose of the EC ITS mandate to the CEPT was to study the possibility of:
• Extending the upper edge of the EC harmonised safety related ITS band (5 875 MHz to 5 905 MHz) by
20 MHz up to 5 925 MHz.
• In addition to road transport, allowing other means of transport such as Urban Rail (using Communication
Based Train Control (CBTC)) in the EC harmonised safety related ITS band.
ETSI
11 ETSI TR 103 704 V1.1.1 (2022-05)
CEPT/ECC concluded in CEPT Report 71 [i.6] and invited ETSI to develop sharing and interference mitigation
techniques with a reasonable timeframe (no more than 3 years), to ensure co-channel coexistence in the frequency range
5 875 MHz to 5 925 MHz between Road ITS and Urban Rail applications, and between Road ITS radio technologies,
by considering the following (see also Figure 1):
"Minimum technical requirements (without any change for Road ITS in 5875-5905 MHz):
• the frequency band 5875-5 925 MHz is designated for all safety related ITS applications (Road ITS and Urban
Rail ITS).
• the frequency band 5 925-5935 MHz is designated for safety-related Urban Rail ITS applications.
• define priority to Road ITS applications below 5 915 MHz and to Urban Rail ITS applications above
5 915 MHz, so that protection is afforded to the application having priority;"

Figure 1: Road ITS and Urban Rail ITS bands
4.2 Available results and studies
ETSI has been conducting studies since 2017 and the outcome was summarized in ETSI TR 103 580 [i.2]. ETSI
TR 103 580 [i.2] focused on the 5 915 MHz to 5 925 MHz band where Urban Rail ITS would have priority and
proposed the following:
• Identify methods to define protected zones.
• Define Protected Zone detection methods.
• Define mitigation techniques to apply in protected zones.
Regarding the definition of protected zones, several methods have been identified. ETSI TR 103 580 [i.2] concluded the
need to conduct a measurement campaign to validate these results and to confirm the simulation parameters which
should be used to define the proper mitigation area to protect Urban Rail communications systems.
ETSI TR 103 580 [i.2] also concluded that further studies are needed on:
• The protected zone detection methods, in particular:
- Read-only database combined with alert beacons.
- Updatable database combined with optional permissive beacons.
• The mitigation techniques to apply in protected zones.
ETSI
12 ETSI TR 103 704 V1.1.1 (2022-05)
5 Critical interference scenarios
5.1 Description of critical interference scenarios
5.1.1 Introduction
A metro Line can leave a tunnel for different reasons:
• At the end of the Line, the last station may be in open air followed by a transfer track where several switches
will distribute the trains to entrances in the depot.
• In suburban area, long section of Line can be in open air because there is more place than in a dense urban area
and in this case an expensive tunnel is not justified.
• In a dense urban area, a metro Line can leave a tunnel because the underground does not allow to drill a tunnel
at an acceptable cost. In this case the metro Line may run on a viaduct.
A metro Line in open air can have:
• One road parallel on one side of the track.
• Two roads parallel to the track with one parallel to each side.
• The tracks and the road can be at different levels:
- tracks and road at the same level;
- tracks on a viaduct or road on a viaduct.
A metro Line in open air can be on a viaduct or a bridge and cross a road. A road on a bridge can also cross a metro
Line in open air.
It is also important to consider that a CBTC base station antenna can receive transmission from different areas in a city.
Several vehicles present in each area can exchange messages. In each area these ones can receive each other and limit
the use of the channel capacity at 62 % with the DCC; but vehicles in the different areas are not able to listen each
other.
Because a CBTC base station has two high gain antennas pointing in two opposite directions, it can receive interference
from several areas and "see" a channel occupancy much higher than 62 %.
5.1.2 Road parallel to Urban Rail tracks
Road parallel to urban rail tracks is a common situation that can be encountered in European cities as shown in Figure
2, Figure 3 and Figure 4.
ETSI
...