ETSI TR 102 960 V1.1.1 (2012-11)

Technical Report
Intelligent Transport Systems (ITS);
Mitigation techniques to avoid interference between European
CEN Dedicated Short Range Communication (RTTT DSRC)
equipment and Intelligent Transport Systems (ITS)
operating in the 5 GHz frequency range;
Evaluation of mitigation methods and techniques

�
2 ETSI TR 102 960 V1.1.1 (2012-11)

Reference
DTR/ITS-0040029
Keywords
DSRC, ITS, radio, RTTT
ETSI
650 Route des Lucioles
F-06921 Sophia Antipolis Cedex - FRANCE

Tel.: +33 4 92 94 42 00  Fax: +33 4 93 65 47 16

Siret N° 348 623 562 00017 - NAF 742 C
Association à but non lucratif enregistrée à la
Sous-Préfecture de Grasse (06) N° 7803/88

Important notice
Individual copies of the present document can be downloaded from:
http://www.etsi.org
The present document may be made available in more than one electronic version or in print. In any case of existing or
perceived difference in contents between such versions, the reference version is the Portable Document Format (PDF).
In case of dispute, the reference shall be the printing on ETSI printers of the PDF version kept on a specific network drive
within ETSI Secretariat.
Users of the present document should be aware that the document may be subject to revision or change of status.
Information on the current status of this and other ETSI documents is available at
http://portal.etsi.org/tb/status/status.asp
If you find errors in the present document, please send your comment to one of the following services:
http://portal.etsi.org/chaircor/ETSI_support.asp
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 2012.
All rights reserved.
TM TM TM
DECT , PLUGTESTS , UMTS and the ETSI logo are Trade Marks of ETSI registered for the benefit of its Members.
TM
3GPP and LTE™ are Trade Marks of ETSI registered for the benefit of its Members and
of the 3GPP Organizational Partners.
GSM® and the GSM logo are Trade Marks registered and owned by the GSM Association.
ETSI
3 ETSI TR 102 960 V1.1.1 (2012-11)
Contents
Intellectual Property Rights . 7
Foreword . 7
Introduction . 7
1 Scope . 8
2 References . 8
2.1 Normative references . 8
2.2 Informative references . 8
3 Definitions, symbols and abbreviations . 9
3.1 Definitions . 9
3.2 Symbols . 9
3.3 Abbreviations . 9
4 CEN DSRC Tolling systems . 10
4.1 Introduction . 10
4.2 Technical Characteristics of the Road side Unit (RSU) . 12
4.2.1 RF characteristics . 12
4.2.2 Antenna . 12
4.3 Technical Characteristics of the Onboard Unit (OBU) . 13
4.3.1 RF characteristics . 13
4.3.2 Antenna . 13
4.4 Protocol Layer . 14
4.5 Interference from ITS-G5 stations . 14
4.5.1 Physical layer . 14
4.5.2 Protocol layer . 14
4.6 Conclusion . 14
5 Coexistence Evaluation: Simulations . 15
5.1 Introduction . 15
5.2 Simulation scenarios and model assumptions . 15
5.3 Simulator 1: SEAMCAT . 15
5.3.1 Overview . 15
5.3.2 Basic properties of SEAMCAT . 16
5.3.3 Radio characteristics used in the SEAMCAT simulation . 17
5.3.3.1 CEN DSRC OBU antenna characteristics . 17
5.3.3.2 ITS-G5 antenna characteristic . 17
5.3.3.3 CEN DSRC OBU receiver . 17
5.3.3.4 ITS-G5 emission mask . 17
5.3.3.5 Radio channel model . 18
5.3.3.6 ITS-G5 transmission burst considerations . 18
5.3.4 SEAMCAT Simulation Scenarios . 18
5.3.4.1 Scenario I: One single interferer in the same lane at fixed position . 18
5.3.4.2 Scenario II: One single interferer in the neighbour lane . 19
5.3.4.3 Scenario III: Three lanes heavy traffic . 19
5.3.4.4 Scenario IV: Seven lanes congestion . 20
5.3.4.5 Scenario V: Seven lanes very heavy traffic scenario . 20
5.3.5 SEAMCAT simulation results . 20
5.3.5.1 Simulation 1: Single interferer at same lane . 20
5.3.5.2 Simulation 2: Single interferer at neighbour lane . 21
5.3.5.3 Simulation 3: Three lanes heavy traffic . 22
5.3.5.4 Simulation 4 and 5: Seven lanes, distinct power levels . 22
5.3.5.5 Simulation 6 and 7: Seven lanes, ITS-G5 TX power control . 23
5.3.5.6 Simulation 8 and 9: Seven lanes, comparison between distinct power levels and ITS-G5 TX
power control for different duty cycles . 24
5.3.5.7 Simulation 10: Seven lanes congested, comparison of different OBU types . 24
5.3.6 Interpretation, Conclusions and Outlook . 25
ETSI
4 ETSI TR 102 960 V1.1.1 (2012-11)
5.4 Simulator 2: CEN DSRC protocol simulator . 26
5.4.1 Simulator 2: Basic properties . 26
5.4.1.1 Simulator 2: Overview . 26
5.4.1.2 Simulator 2: Configuration . 27
5.4.1.2.1 Simulator 2: Configuration overview . 27
5.4.1.2.2 ITS-G5 configuration . 28
5.4.1.2.3 Mobility simulator configuration . 28
5.4.1.2.4 CEN DSRC OBU configuration and CEN DSRC transaction configuration . 29
5.4.1.2.5 CEN DSRC RSU configuration . 29
5.4.2 Simulator 2: Simulation scenario overview . 30
5.4.3 Simulator 2 results: Calibration . 31
5.4.4 Simulator 2 results: Evaluation of LDC parameters . 33
5.4.4.1 Simulation details . 33
5.4.4.2 Interference to one OBU . 33
5.4.4.3 Interference to two simultaneous CEN DSRC transactions . 33
5.4.4.4 Interference to three simultaneous CEN DSRC transactions . 36
5.4.5 Simulator 2 results: Complex traffic scenarios . 36
5.4.5.1 Fast traffic scenario . 36
5.4.5.2 Truck scenario . 38
5.4.5.3 Toll Plaza . 40
5.4.5.4 Slow traffic . 44
5.4.5.5 Light traffic . 47
5.5 The T model . 47
off
5.5.1 Derivation of the T model . 47
off
5.5.2 T model equation . 49
off
5.5.3 T model evaluation . 49
off
5.6 Conclusion . 50
6 Coexistence Evaluation: Measurements . 51
6.1 Introduction . 51
6.2 Measurement setup and scenarios . 51
6.2.1 Configurations . 51
6.2.1.1 Configuration 1; CF#1: Reference measurements . 52
6.2.1.2 Configuration 2; CF#2: RSU-OBU reference measurements . 53
6.2.1.3 Configuration 3; CF#3: Interference evaluation measurements . 54
6.2.1.4 Car configuration . 54
6.2.2 Interference signal generation . 56
6.2.3 Reference measurements . 56
6.2.3.1 Reference measurement interference signal . 56
6.2.3.2 Reference measurement CEN DSRC tolling system . 57
6.2.3.3 BER reference measurement at the CEN DSRC tolling system with ITS interference . 58
6.2.4 Measurement 1: OBU Interference sensitivity pattern . 59
6.2.4.1 OBU sensitivity evaluation measurement . 60
6.2.5 Measurement 2: Single interferer from front . 61
6.2.5.1 OBU Interference for different duty cycles, front position . 62
6.2.6 Measurement 3: Single ITS-G5A Station installed on rooftop . 63
6.2.6.1 OBU Interference power levels, ITS on rooftop . 65
6.2.7 Measurement 4: Multiple interferer using ITS system emulator . 65
6.3 Measurements Results . 67
6.3.1 Calibration . 67
6.3.1.1 Measurements with a reference RX antenna (TD_CAL_01) . 67
6.3.1.1.1 Test run and evaluation details . 67
6.3.1.1.2 Azimuth scan . 67
6.3.1.1.3 Elevation scan . 68
6.3.1.2 CEN DSRC power level at OBU position (TD_CAL_02) . 69
6.3.1.2.1 Test run and evaluation details . 69
6.3.1.2.2 CEN DSRC power level at OBU mounted in the convertible . 70
6.3.1.2.3 CEN DSRC power level at OBU mounted in the SUV . 70
6.3.1.3 CEN DSRC BER for interferer from the front (TD_CAL_03) . 71
6.3.1.3.1 Test run and evaluation details . 71
6.3.1.3.2 Comparison of interference limits of different OBU types . 73
6.3.2 Measurement 1: OBU Interference sensitivity pattern . 74
ETSI
5 ETSI TR 102 960 V1.1.1 (2012-11)
6.3.2.1 Test run and evaluation details . 74
6.3.2.2 OBU sensitivity evaluation measurement (TD_COEX_OBU_01) . 75
6.3.2.2.1 TD_COEX_OBU_01: Test run 1 . 75
6.3.2.2.2 TD_COEX_OBU_01: Test run 2 . 77
6.3.2.2.3 TD_COEX_OBU_01: Test run 3 . 79
6.3.2.2.4 TD_COEX_OBU_01: Test run 4 . 81
6.3.2.2.5 TD_COEX_OBU_01: Test run 5 . 83
6.3.2.2.6 TD_COEX_OBU_01: Test run 6 . 86
6.3.3 Measurement 2: Single interferer with different duty cycles . 88
6.3.3.1 Result evaluation and coexistence limits . 88
6.3.3.2 Test results for OBU10 (TD_COEX_OBU_02) . 90
6.3.3.3 Test results for OBU12 (TD_COEX_OBU_02) . 91
6.3.4 Measurement 3: Single ITS-G5A Station installed on rooftop . 92
6.3.4.1 Test run and evaluation details . 92
6.3.4.2 Test results for OBU12 (TD_COEX_OBU_03) . 92
6.3.5 Measurement 4: Multiple interferer using ITS system emulator . 93
6.3.5.1 Test run and evaluation details . 93
6.3.5.2 Measurement 4 results . 93
6.4 Summary of measurement results. 94
7 Conclusions and further steps. 95
7.1 Critical scenarios . 95
7.2 Propose mitigation measures . 95
7.2.1 Conclusions and consequences . 95
7.2.2 Determination of idle time T . 95
off
7.2.3 Determination of the transmit power level limit . 96
7.2.4 Determination of bust time T . 96
on
7.3 Further steps . 96
Annex A: Detailed Measurement Results . 97
A.1 Introduction . 97
A.2 Calibration . 97
A.2.1 Substitution Antenna Measurements (TD_CAL_01) . 97
A.2.1.1 Test run and evaluation details . 97
A.2.1.2 Azimuth scan . 98
A.2.1.3 Elevation scan . 100
A.2.2 CEN DSRC power level at OBU position (TD_CAL_02) . 101
A.2.3 CEN DSRC BER for interferer from the front (TD_CAL_03) . 101
A.2.3.1 Test run and evaluation details . 101
A.2.3.2 BER evaluation . 102
A.3 Measurement 1: OBU Interference susceptibility pattern . 105
A.3.1 Test run and evaluation details . 105
A.3.2 OBU sensitivity evaluation measurement (TD_COEX_OBU_01) . 106
A.3.2.1 TD_COEX_OBU_01: Test run 1 . 106
A.3.2.2 TD_COEX_OBU_01: Test run 2 . 107
A.3.2.3 TD_COEX_OBU_01: Test run 3 . 108
A.3.2.4 TD_COEX_OBU_01: Test run 4 . 109
A.3.2.5 TD_COEX_OBU_01: Test run 5 . 110
A.3.2.6 TD_COEX_OBU_01: Test run 6 . 111
A.4 Measurement 2 . 112
A.4.1 Statistic evaluation of the test results . 112
A.4.2 OBU10 results . 113
A.4.3 OBU12 results . 115
A.5 Measurement 3 . 117
Annex B: Models used for simulation and evaluation . 119
B.1 Introduction . 119
B.2 CEN DSRC OBU antenna characteristics used in SEAMCAT and simulator 2 . 119
ETSI
6 ETSI TR 102 960 V1.1.1 (2012-11)
B.2.1 General antenna model properties . 119
B.2.2 TD_CAL_01 antenna model . 119
B.2.3 TD_COEX_OBU_01 run 1 interference limit pattern of OBU11 . 120
B.2.4 TD_COEX_OBU_01 run 2 interference limit pattern of OBU2 . 121
B.2.5 TD_COEX_OBU_01 run 3 interference limit pattern of OBU10 . 122
B.2.6 TD_COEX_OBU_01 run 5 interference limit pattern of OBU6 . 123
B.2.7 TD_COEX_OBU_01 run 6 interference limit pattern of OBU9 . 124
Annex C: CEN DSRC protocol simulator details. 125
C.1 Simulator configuration parameters . 125
C.2 CEN DSRC OBU simulator configuration details . 127
C.3 CEN DSRC OBU simulator simulation results . 131
C.3.1 OBU9 . 131
C.3.1.1 Interference to one OBU9 . 131
C.3.1.2 Interference to two simultaneous CEN DSRC transactions with OBU9 . 133
C.3.1.3 Interference to 3 simultaneous CEN DSRC transactions with OBU9 . 138
Annex D: Bibliography . 141
History . 143

ETSI
7 ETSI TR 102 960 V1.1.1 (2012-11)
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 Intelligent Transport System (ITS).
Introduction
Without the use of special mitigation techniques, European CEN Dedicated Short Range Communication (DSRC)
equipment operating in the frequency range from 5 795 MHz to 5 815 MHz might suffer from harmful interference
caused by Intelligent Transport Systems (ITS) using adjacent frequency bands. The present document will evaluate the
detailed need of mitigation techniques and the corresponding parameters to avoid this interference. The evaluation is
based on simulations and measurements.
ETSI
8 ETSI TR 102 960 V1.1.1 (2012-11)
1 Scope
The present document presents the results of the evaluation of the potential coexistence issues between ITS-G5 and
CEN DSRC tolling systems. The evaluation tests take into account a broad range of DSRC OBUs from different
manufacturers. The evaluation consists of the definition of the evaluation scenarios, simulation results and results of
evaluation measurements.
The present document is indented to guide the further work on coexistence mechanisms in ITS-G5 in order to guarantee
a smooth coexistence between ITS-G5 and CEN DSRC systems.
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.
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] CEN EN 12795: "Road transport and traffic telematics - Dedicated Short Range, Communication
(DSRC) - DSRC data link layer: medium access and logical link control".
[i.2] CEN EN 13372: "Road transport and traffic telematics - Dedicated Short Range Communication
(DSRC) - Profiles for RTTT applications".
[i.3] CEN EN 12253: "Road transport and traffic telematics - Dedicated Short Range Communication
(DSRC) - Physical layer using microwave at 5,8 GHz".
[i.4] ETSI TR 102 654: "Electromagnetic compatibility and Radio spectrum Matters (ERM); Road
Transport and Traffic Telematics (RTTT); Co-location and Co-existence Considerations regarding
Dedicated Short Range Communication (DSRC) transmission equipment and Intelligent Transport
Systems (ITS) operating in the 5 GHz frequency range and other potential sources of interference".
[i.5] ETSI ES 202 663: "Intelligent Transport Systems (ITS); European profile standard for the physical
and medium access control layer of Intelligent Transport systems operating in the 5 GHz
frequency band".
[i.6] CEN EN 15509: "Road transport and traffic telematics - Electronic fee collection; Interoperability
application profile DSRC".
[i.7] ETSI TS 102 792: "Intelligent Transport Systems (ITS); Mitigation techniques to avoid
interference between European CEN Dedicated Short Range Communication (CEN DSRC)
equipment and Intelligent Transport Systems (ITS) operating in the 5 GHz frequency range".
ETSI
9 ETSI TR 102 960 V1.1.1 (2012-11)
[i.8] ETSI TS 102 687: "Intelligent Transport Systems (ITS); Decentralized Congestion Control
Mechanisms for Intelligent Transport Systems operating in the 5 GHz range; Access layer part".
[i.9] D.COMM.x.x, CVIS project deliverable: "CVIS COMM Interference measurements test report",
February 2010.
[i.10] IEEE 802.11-2012: "IEEE Standard for Information technology--Telecommunications and
information exchange between systems Local and metropolitan area networks--Specific
requirements Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY)
Specifications".
3 Definitions, symbols and abbreviations
3.1 Definitions
For the purposes of the present document, the following terms and definitions apply:
Mode A: Typical case with a typical path loss attenuation between RSU and OBU and e.g. 6 dB above sensitivity limit
Mode B: Worst case with a path attenuation leading to an operation of the OBU at the sensitivity limit
3.2 Symbols
For the purposes of the present document, the following symbols apply:
P ITS Transmit power level
ITS
PL Path loss
PL Reference Path Loss
P Received Power
RX
P Power Setting
s
P Transmit Power
TX
3.3 Abbreviations
For the purposes of the present document, the following abbreviations apply:
AIFS Arbitration InterFrame Space
BER Bit Error Ratio
BST Beacon Service Table
BW Bandwidth
CAM Cooperative Awareness Message
CEN Comité Européen de Normalisation
CEPT Conférence Européenne des administrations des Postes et des Télécommunications
CF Configuration
C/I Carrier-to-Interference ratio
CVIS Cooperative Vehicle-Infrastructure Systems
dBm dB Milliwatt
DCC Decentralized Congestion Control
DFT Discrete Fourier Transform
dRSS SEAMCAT parameter, desired Received Signal Strength
DSRC Dedicated Short Range Communication
ECC Electronic Communications Committee
EIRP Equivalent Isotropic Radiated Power
EMSL European Microwave Signature Laboratory
EN European Norm
ETSI European Telecommunications Standards Institute
iRSSblocking SEAMCAT parameter, interfering received signal strength blocking
ETSI
10 ETSI TR 102 960 V1.1.1 (2012-11)
iRSSunwanted SEAMCAT parameter, interfering received signal strength unwanted signal
JRC Joint Research Center
IEEE Institute of Electrical and Electronics Engineers
IPR Intellectual Property Rights
ISO International Standardisation Organisation
ITS Intelligent Transport System
ITS-G5 acronym for the 5,9 GHz vehicular adhoc network PHY
LDC Low Duty Cycle
LHCP Left Hand Circular Polarized
MAC Medium Access Control
N/A Not applicable
OBU OnBoard Unit
PHY PHYsical (OSI layer)
RBW Resolution Bandwidth
RF Radio Frequency
RSU RoadSide Unit
RX Receive
SEAMCAT Spectrum Engineering Advanced Monte Carlo Analysis Tool
SUT System Under Test
SUV Sport Utility Vehicule
TER CEN DSRC Transaction Error Ratio
TS Technical Specification
TX Transmit
VBW Video Bandwidth
4 CEN DSRC Tolling systems
4.1 Introduction
In this clause the main technical and operational characteristics of the investigated CEN DSRC tolling systems are
depicted. The focus is on the deployment scenarios and the critical operational conditions where a potential interference
from ITS-G5 systems might occur. A typical tolling zone geometry is depicted in figure 1 for a two lane scenario. The
interference from an ITS-G5 system can only occur during the transaction between the Road Side Unit (RSU) and the
On Board Unit (OBU) in the tolling zone. Another possible interference effect could be the wake up of the OBU from
the power save mode initiated by ITS signals.
ETSI
11 ETSI TR 102 960 V1.1.1 (2012-11)
Lane Width
Tolling Zone
CEN DSRC RSU
CENDSRCRSU
Tolling Zone
Lane Width
Figure 1: Typical tolling zone geometries for a two lane free flow scenario
Three main tolling station types need to be differentiated:
• Free-Flow tolling stations and enforcement stations with a maximum of 6 parallel lanes (typical 3 to 4 lanes in
each traffic direction)
• Toll plazas with an automatic barrier with up to 40 parallel lanes (Typical around 10 to 20 lanes in each traffic
direction)
• Toll plazas with automatic lanes (reduced speed) with up to 40 parallel lanes (typical around 1 to 10 lanes in
each traffic direction)
Figure 2: Typical free-flow installation with three lanes
ETSI
10 m
10 m
12 ETSI TR 102 960 V1.1.1 (2012-11)

Figure 3: Typical toll plaza with an automatic barrier (left) and automatic lanes (right)
4.2 Technical Characteristics of the Road side Unit (RSU)
4.2.1 RF characteristics
Detailed characteristics are defined in table 1 (from TR 102 654 [i.4]).
Table 1: Parameters of a typical RSU
DSRC Road Side Unit (RSU) Value Units
Receiver bandwidth 500 kHz
Receiver sensitivity -104 dBm
Antenna gain bore sight 13 dBi
Antenna gain outside RSU active angle
(worst case as in [i.3]) -2 dBi
Antenna polarization LHCP
cross-polar discrimination,
10 dB
ellipticity of polarization
TX output power level, EIRP 33 dBm
RSU mounting height above ground 2,5 to 7 m
Protection criterion (S/I) 6 dB
TX Frequency / Bandwidth see clause 5.1 [i.4]

4.2.2 Antenna
The RSU antenna is tilted downside for the interrogation of the onboard units. Outside of the main beam the antenna
has reduced gain by a factor of around -15 dB [i.3]. The typical main beam e.i.r.p. is 33 dBm leading to an e.i.r.p of
around 18 dBm outside of the main beam. A typical setup is depicted in figure 4. A large part of the 10 m tolling zone is
covered by the main beam.
18dBm
33dBm
l … detection distance
d
l = 10 m
c
Figure 4: Typical Antenna characteristics of a RSU antenna
ETSI
13 ETSI TR 102 960 V1.1.1 (2012-11)
In a multilane set up with several parallel lanes a single RSU will cover more than a single lane. This leads to an
overlap between two adjacent RSUs. By doing so, a better coverage can be guaranteed.
4.3 Technical Characteristics of the Onboard Unit (OBU)
4.3.1 RF characteristics
Detailed characteristics are defined in table 2 (from TR 102 654 [i.4]).
Table 2: Parameters of a typical OBU
DSRC On Board Unit (OBU) Value Units
OBU sensitivity (typical) -60 to -50 dBm
Wakeup sensitivity -60 to -43 dBm
Antenna polarization LHCP
cross-polar discrimination,
6 dB
ellipticity of polarization
Car windscreen loss 3 dB
OBU mounting height above ground 1 to 2,2 m
Protection criterion (S/I) 10 dB
TX Frequency / Bandwidth see clause 5.1 [i.4]

4.3.2 Antenna
The typical antenna pattern of an CEN DSRC OBU in boresight is given in figure 5. This antenna pattern is the
standalone OBU antenna pattern. The effective antenna patterns including the car attenuations will be presented in the
result section of the present document.
In a passenger car the OBU is tilted, and bore sight is directed upwards. A measured azimuth (horizontal) antenna
diagram for such a tilted OBU antenna is shown in figure 6.

Figure 5: Typical isolated antenna pattern of a CEN DSRC On Board unit (OBU) in boresight
ETSI
14 ETSI TR 102 960 V1.1.1 (2012-11)

Figure 6: Typical isolated antenna pattern of a CEN DSRC On Board unit (OBU)
tilted by 70° as usual when mounted in a passenger car
4.4 Protocol Layer
The basics of the timing of a CEN DSRC transaction are defined by CEN EN 12795 [i.1]. Timing details are application
specific and different for each toll operator and toll station type (see clause 4.1). Additionally the OBU type can have an
influence on the timing behaviour (e.g. the late response procedure as defined in CEN EN 13372 [i.2]).
The timing behaviour of a CEN DSRC transaction can be exploited to optimize the coexistence properties.
4.5 Interference from ITS-G5 stations
4.5.1 Physical layer
See ES 202 663 [i.5].
4.5.2 Protocol layer
See ES 202 663 [i.5] and the additional standards under development within ETSI TC ITS.
4.6 Conclusion
The presented technical characteristics and deployment scenarios of the two considered systems (CEN DSRC and
ITS-G5) lead to the conclusion that coexistence in the same geographic area between the systems is possible only under
certain restrictions on the ITS system. The present document will evaluate specific rules to guarantee this coexistence
without harmful degradation of the systems' performance.
ETSI
15 ETSI TR 102 960 V1.1.1 (2012-11)
5 Coexistence Evaluation: Simulations
5.1 Introduction
The coexistence evaluation based on simulation should support the evaluation measurements in order to better
understand the interference mechanism and especially the effect of a large number of independent interferers which
cannot be evaluated in a real measurement without a large effort. In an initial step the simulations should confirm/verify
the critical scenarios defined. The simulation results should then be used to evaluate the critical parameters in these
scenarios, like the maximum allowed ITS TX power, number of devices or the critical activity factors of single devices
and of the overall ITS system.
5.2 Simulation scenarios and model assumptions
5.3 Simulator 1: SEAMCAT
5.3.1 Overview
In order to introduce radio systems for transport systems (Intelligent Transport Systems - ITS) in the frequency range
between 5,875 GHz to 5,905 GHz it is essential to ensure the c
...