ETSI EN 302 890-2 V2.1.1 (2020-10)

ETSI EN 302 890-2 V2.1.1 (2020-10)






EUROPEAN STANDARD
Intelligent Transport Systems (ITS);
Facilities Layer function;
Part 2: Position and Time management (PoTi);
Release 2

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2 ETSI EN 302 890-2 V2.1.1 (2020-10)



Reference
DEN/ITS-00182
Keywords
facility, ITS, time-stamping

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
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:
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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 2020.
All rights reserved.

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.
ETSI

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3 ETSI EN 302 890-2 V2.1.1 (2020-10)
Contents
Intellectual Property Rights . 5
Foreword . 5
Modal verbs terminology . 5
Introduction . 6
1 Scope . 7
2 References . 7
2.1 Normative references . 7
2.2 Informative references . 8
3 Definition of terms, symbols and abbreviations . 9
3.1 Terms . 9
3.2 Symbols . 9
3.3 Abbreviations . 10
4 Position and Time entity introduction . 11
4.1 Introduction . 11
4.2 Service provided by the PoTi entity . 12
5 PoTi functional description . 12
5.1 PoTi in the ITS Domain . 12
5.2 ITS Constellation . 12
5.3 PoTi in the ITS Station (ITS-S) architecture . 13
5.4 PoTi entity functional architecture . 14
5.4.1 General . 14
5.4.2 Position information Management . 14
5.4.3 Position Augmentation . 15
5.4.4 Reference coordinate System Conversion . 15
5.4.5 Time information Management . 15
5.4.6 Time synchronization . 15
5.4.7 Time reference system conversion Service . 15
5.5 PoTi Interfaces . 16
5.5.1 Interface to ITS applications (FA-SAP). 16
5.5.2 Interfaces to the Networking and Transport Layer (NF-SAP) . 17
5.5.3 Interfaces to the Management entity (MF-SAP) . 17
5.5.4 Interfaces to the Security entity (SF-SAP) . 17
5.5.5 Interfaces to other Facility layer entities . 18
6 Position and time requirements . 18
6.1 Requirements related to PoTi functions . 18
6.2 ITS-S reference position . 20
6.2.1 Introduction. 20
6.2.2 ITS-S reference position for passenger cars . 20
6.2.3 ITS-S reference position for Trucks . 22
6.2.4 ITS-S reference position for Busses . 28
6.2.5 ITS-S reference position for Motorcycles, mopeds and bicycles . 29
6.2.6 ITS-S reference position for Pedestrians . 31
6.2.7 ITS-S reference position for Special Vehicles . 31
6.2.8 ITS-S reference position for City-Tram . 31
6.2.9 ITS-S reference position for Roadside ITS Stations (R-ITS-Ss) . 32
6.3 Position and time confidence. 32
6.3.1 General requirements related to confidence . 32
6.3.2 Confidences related to Position Information Management . 33
6.3.2.1 Horizontal Position confidence . 33
6.3.2.2 Vertical Position confidence . 33
6.3.2.3 Horizontal Speed confidence . 33
6.3.2.4 Heading confidence . 33
ETSI

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4 ETSI EN 302 890-2 V2.1.1 (2020-10)
6.3.2.5 Confidence of other quantities . 34
6.3.2.6 Other accuracy estimations . 34
6.3.3 Confidences related to Reference Coordinate System Conversion Management . 34
6.3.3.1 Relative Position confidence . 34
6.3.4 Confidences related to Time Information Management . 34
7 Augmentation services . 35
7.1 Introductions . 35
7.2 GNSS Positioning Correction (GPC) Augmentation Service . 35
7.2.1 Introduction. 35
7.2.2 GPC requirements . 36
7.2.3 GPC Data processing by the V-ITS-S during transition between R-ITS-S service areas . 36
7.3 R-ITS-S ranging augmentation Service . 37
7.3.1 Introduction. 37
7.3.2 Ranging service announcements . 38
7.3.2.1 Introduction . 38
7.3.2.2 Ranging Service Application Data . 39
7.3.3 Measurement. 40
7.3.4 Ranging Rate . 40
7.3.5 Security . 40
Annex A (normative): ASN.1 specification of messages . 41
A.1 ASN.1 specification of ranging service application data . 41
History . 42


ETSI

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5 ETSI EN 302 890-2 V2.1.1 (2020-10)
Intellectual Property Rights
Essential patents
IPRs essential or potentially essential to normative deliverables 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 (https://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.
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.
Foreword
This European Standard (EN) has been produced by ETSI Technical Committee Intelligent Transport Systems (ITS).
The present document is part 2 of a multi-part deliverable covering Facilities Layer function, as identified below:
Part 1: "Services Announcement (SA) specification";
Part 2: "Position and Time management (PoTi); Release 2".
The present document is based on inputs provided by various European projects including AutoNet, Concorda,
Ensemble, Hights, PRoPART, Dutch-Germany-Austria Corridor, Scope@F, A58 (NL), PRE-DRIVE C2X, DRIVE
C2X, SafeSpot, CVIS, CoVeL, SCOR@F, simTD, etc.

National transposition dates
Date of adoption of this EN: 19 October 2020
Date of latest announcement of this EN (doa): 31 January 2021
Date of latest publication of new National Standard
or endorsement of this EN (dop/e): 31 July 2021
Date of withdrawal of any conflicting National Standard (dow): 31 July 2021

Modal verbs terminology
In the present document "shall", "shall not", "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.
ETSI

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6 ETSI EN 302 890-2 V2.1.1 (2020-10)
Introduction
Intelligent Transportation Systems Cooperative, Connected and Automated Mobility (CCAM) related use cases in the
ITS environment as specified in the ETSI ITS architecture (ETSI EN 302 665 [i.1]) can be distributed over multiple ITS
stations (ITS-Ss). ITS-Ss interact in the ITS system to exchange sensor data and traffic related information to make each
other aware of traffic safety or traffic efficiency circumstances and situations by which each ITS-S equipped road user,
whether automated or not, can improve their safety and efficiency related decisions.

ETSI

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7 ETSI EN 302 890-2 V2.1.1 (2020-10)
1 Scope
The present document provides the specification of the Position and Time (PoTi) services. It includes functional and
operational requirements for the position and time data to support ITS Applications. In addition, it includes the
definition of syntax and semantics of messages exchanged between ITS Stations (ITS-Ss) to augment the position and
time accuracy. Finally, it specifies the facilities layer protocol in support of such message exchanges.
2 References
2.1 Normative 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.
Referenced documents which are not found to be publicly available in the expected location might be found at
https://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.
The following referenced documents are necessary for the application of the present document.
[1] ETSI TS 103 301: "Intelligent Transport Systems (ITS); Vehicular Communications; Basic Set of
Applications; Facilities layer protocols and communication requirements for infrastructure
services".
[2] RTCM 10402.3: "Recommended Standards for Differential GNSS (Global Navigation Satellite
Systems) Service".
[3] RTCM 10403.3: "Differential GNSS (Global Navigation Satellite Systems) Services - Version 3".
[4] ETSI EN 302 663 (V1.3.1) (01-2020): "Intelligent Transport Systems (ITS); ITS-G5 Access layer
specification for Intelligent Transport Systems operating in the 5 GHz frequency band".
[5] ETSI EN 302 890-1 (V1.2.1) (07-2019): "Intelligent Transport Systems (ITS); Facilities layer
function; Part 1: Services Announcement (SA) specification".
[6] World Geodetic System 1984 (WGS84).
NOTE: Available at http://earth-info.nga.mil/GandG/update/index.php?dir=wgs84&action=wgs84#tab_wgs84-
res.
[7] ISO 8855 (2011): "Road Vehicles -- Vehicle dynamics and road-holding ability -- Vocabulary".
[8] ETSI TS 103 248: "Intelligent Transport Systems (ITS); GeoNetworking; Port Numbers for the
Basic Transport Protocol (BTP)".
[9] ISO 5725-1 (1994): "Accuracy (trueness and precision) of measurement methods and results --
Part 1: General principles and definitions".
[10] ETSI TS 102 894-2: "Intelligent Transport Systems (ITS); Users and applications requirements;
Part 2: Applications and facilities layer common data dictionary".
[11] ETSI EN 302 931 (V1.1.1): "Intelligent Transport Systems (ITS); Vehicular Communications;
Geographical Area Definition".
[12] ISO/TS 16460:2016: "Intelligent transport systems -- Communications access for land mobiles
(CALM) -- Communication protocol messages for global usage".
ETSI

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8 ETSI EN 302 890-2 V2.1.1 (2020-10)
[13] Recommendation ITU-T X.691/ISO/IEC 8825-2:2015: "Information technology - ASN.1 encoding
rules: Specification of Packed Encoding Rules (PER)".
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 with regard to a particular subject area.
[i.1] ETSI EN 302 665: "Intelligent Transport Systems (ITS); Communications Architecture".
[i.2] ETSI TR 102 638 (V1.1.1): "Intelligent Transport Systems (ITS); Vehicular Communications;
Basic Set of Applications; Definitions".
[i.3] ETSI EN 302 637-2: "Intelligent Transport Systems (ITS); Vehicular Communications; Basic Set
of Applications; Part 2: Specification of Cooperative Awareness Basic Service".
[i.4] ETSI EN 302 637-3: "Intelligent Transport Systems (ITS); Vehicular Communications; Basic Set
of Applications; Part 3: Specifications of Decentralized Environmental Notification Basic
Service".
[i.5] ETSI TS 102 894-1 (V1.1.1): "Intelligent Transport Systems (ITS); Users and applications
requirements; Part 1: Facility layer structure, functional requirements and specifications".
[i.6] ETSI TR 103 299: "Intelligent Transport System (ITS); Cooperative Adaptive Cruise Control
(CACC); Pre-standardization study".
[i.7] ETSI TS 103 324: "Intelligent Transport Systems (ITS); Cooperative Perception Services".
[i.8] ETSI TS 103 246-1 (V1.2.1) (03-2017): "Satellite Earth Stations and Systems (SES); GNSS based
location systems; Part 1: Functional requirements".
[i.9] EUREF: "European Terrestrial Reference System 89 (ETRS89)".
NOTE: Available at http://etrs89.ensg.ign.fr.
[i.10] ETSI TR 101 607 (V1.1.1) (05-2013): "Intelligent Transport Systems (ITS); Cooperative ITS
(C-ITS); Release 1".
[i.11] ISO 3534-1 (10-2009): "Statistics - Vocabulary and symbols - Part 1: General statistical terms and
terms".
[i.12] ETSI TS 136 305 (V11.2.0): "LTE; Evolved Universal Terrestrial Radio Access Network
(E-UTRAN); Stage 2 functional specification of User Equipment (UE) positioning in E-UTRAN
(3GPP TS 36.305 version 11.2.0 Release 11)".
[i.13] IETF RFC 5905 (June 2010): "Network Time Protocol Version 4: Protocol and Algorithms
Specification".
[i.14] IEC 60050: "International Electrotechnical Vocabulary", 113-01-08 (instant), 113-01-10 (time
interval), 113-01-13 (duration).
[i.15] IS-QZSS-L6-001: "Quasi-Zenith Satellite System Interface Specification Centimeter Level
Augmentation Service".
NOTE: Available at https://qzss.go.jp/en/technical/download/pdf/ps-is-qzss/is-qzss-l6-001.pdf.
[i.16] IETF RFC 8173 (June 2017): "Precision Time Protocol Version 2 (PTPv2) Management
Information Base".
ETSI

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9 ETSI EN 302 890-2 V2.1.1 (2020-10)
[i.17] EN ISO 22418: "Intelligent transport systems - Fast service announcement protocol (FSAP) for
general purposes in ITS" (produced by CEN).
TM
1609.3: "IEEE Standard for Wireless Access in Vehicular Environments (WAVE) --
[i.18] IEEE
Networking Services".
3 Definition of terms, symbols and abbreviations
3.1 Terms
For the purposes of the present document, the following terms apply:
accuracy: closeness of a measured value to a standard or known value
heading: orientation of the horizontal velocity vector with respect to the WGS84 [6] North (clockwise), unless
otherwise noted
horizontal speed: magnitude of horizontal velocity-vector of the reference position point
horizontal velocity vector: projection of the 3D velocity vector on the WGS84 [6] ellipsoid
integrity risk: probability, per unit of time, of having a Parameter Failure without issuing an alert within the
Time-to-Alert
ITS constellation: group of ITS-Ss which are exchanging ITS data among themselves
ITS time: time based on TAI
st
NOTE: Epoch of this time is set to 2004-01-01T00:00:00Z, that is 0 seconds on 1 of January 2004 UTC.
parameter failure: failure occurring when the position and time entity is unable to estimate parameters with an error
less than the maximum tolerable error (err > err_max)
position integrity: measure of the trust that can be placed in the correctness of the estimated Parameters supplied by the
Position and Time entity
NOTE: Integrity includes the ability of the equipment (at the Position and Time entity and/or User level) to
compute timely and valid alerts when the estimated Parameters do not need to be used for the operation of
interest.
protection level: estimated bound on the Parameter Error from the Position and Time entity at a defined confidence
level such as 50 %, 75 %, 95 %, 99 %, etc., delivered with the Parameters
station clock: clock representing ITS time in an ITS Station
Time-to-Alert: maximum allowable elapsed time from the onset of a Parameter Failure until the equipment annunciates
the alert
velocity: vector indicating speed in a particular direction
vertical velocity vector: projection of the 3D velocity vector on the normal vector of the WGS84 [6] Ellipsoid
3.2 Symbols
For the purposes of the present document, the following symbols apply:
Tsys ITS Station Time
ETSI

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10 ETSI EN 302 890-2 V2.1.1 (2020-10)
3.3 Abbreviations
For the purposes of the present document, the following abbreviations apply:
3D 3 Dimensional
ACC Automatic Crouse Control
ACK Acknowledgement
ASN Abstract Syntax Notation
BSA Basic Set of Applications
CA Cooperative Awareness (service)
CACC Cooperative Adaptive Cruise Control
CAM Cooperative Awareness Message
CCAM Cooperative, Connected and Automated Mobility
CDD Common Data Dictionary
CP Collective Perception (service)
CVIS Cooperative Vehicle-Infrastructure Systems
DEN Decentralized Environmental Notification
DENM Decentralized Environmental Notification Message
D-GNSS Differential Global Navigation Satellite System
ECU Electronic Control Unit
EDAS EGNOS Data Access Service
EGNOS European Geostationary Navigation Overlay Service
EU European Union
FA-SAP Facilities to Applications Service Access Point
GLONASS GLObal NAvigation Satellite System
GNSS Global Navigation Satellite Systems
GPC GNSS Positioning Correction
GPS Global Positioning System
GRM GPS Raw data Message
IEC International Electrotechnical Commission
IETF Internet Engineering Task Force
ISO International Organization for Standardization
ITRF International Terrestrial Reference Frame
ITS Intelligent Transport Systems
ITS-C ITS Constellation
ITS-S ITS Station
ITU-T International Telecommunication Union - Telecommunication standardization sector
MAC Media Access Control
NA Not Applicable
NF-SAP Network to Facilities Service Access Point
NGA National Geospatial-intelligence Agency
NRTK Network Real Time Kinematic
NTP Network Time Protocol
PDU Protocol Data Unit
PoTi Position and Time
PPP Precise Point Positioning
PSID Provider Service Identifier
RAN Radio Access Network
RF Radio Frequency
RFC Request For Comment
R-ITS-S Roadside ITS Station
RTCM Radio Technical Commission for Maritime services
RTCMEM Radio Technical Commission for Maritime services Environmental Message
RTK Real Time Kinematic
SA Service Announcement
SAM Service Announcement Message
SF-SAP Security to Facilities Service Access Point
SI Standard International
SIFS Short InterFrame Space
SLR Satellite Laser Ranging
SPATEM Signal Phase And Timing Extended Message
ETSI

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11 ETSI EN 302 890-2 V2.1.1 (2020-10)
SSR Sirius Satellite Radio
TAI International Atomic Time scale
TCU Transmission Control Unit
ToF Time-of-Flight
UE User Equipment
UPER Unaligned Packet Encoding Rules
UTC Coordinated Universal Time
UWB Ultra Wide Band
VLBI Very-Long-Baseline Interferometry
VRU Vulnerable Road User
WGS World Geodetic System
WGS84 World Geodetic System 1984
4 Position and Time entity introduction
4.1 Introduction
ITS applications such as specified in the Basic Set of Applications specification (BSA) ETSI TR 102 638 [i.2] require
the exchange of position and time information as part of the information exchange among ITS-Ss. As initial ITS
location based services, the Cooperative Awareness (CA) basic service ETSI EN 302 637-2 [i.3] and similar, the road
traffic event Decentralized Environmental Notification (DEN) basic service ETSI EN 302 637-3 [i.4] are developed.
These services and their data exchanges are dependent on position and time information. In this and the following
clauses it is understood that "position" means kinematic and attitude state as defined in clause 5.4.1 which includes
attitude and movement parameters including velocity, heading, horizontal speed and optionally others.
In order to realize road ITS safety related applications, ITS-Ss need to have an absolute k
...

SLOVENSKI STANDARD
SIST EN 302 890-2 V2.1.1:2020
01-december-2020
Inteligentni transportni sistemi (ITS) - Funkcija zmogljivostne plasti - 2. del:
Upravljanje položaja in časa (PoTi) - Izdaja 2
Intelligent Transport Systems (ITS) - Facilities Layer function - Part 2: Position and Time
management (PoTi) - Release 2
Ta slovenski standard je istoveten z: ETSI EN 302 890-2 V2.1.1 (2020-10)
ICS:
35.240.60 Uporabniške rešitve IT v IT applications in transport
prometu
SIST EN 302 890-2 V2.1.1:2020 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 302 890-2 V2.1.1:2020

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SIST EN 302 890-2 V2.1.1:2020
ETSI EN 302 890-2 V2.1.1 (2020-10)






EUROPEAN STANDARD
Intelligent Transport Systems (ITS);
Facilities Layer function;
Part 2: Position and Time management (PoTi);
Release 2

---------------------- Page: 3 ----------------------
SIST EN 302 890-2 V2.1.1:2020
 2 ETSI EN 302 890-2 V2.1.1 (2020-10)



Reference
DEN/ITS-00182
Keywords
facility, ITS, time-stamping

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
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
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 2020.
All rights reserved.

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.
ETSI

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SIST EN 302 890-2 V2.1.1:2020
 3 ETSI EN 302 890-2 V2.1.1 (2020-10)
Contents
Intellectual Property Rights . 5
Foreword . 5
Modal verbs terminology . 5
Introduction . 6
1 Scope . 7
2 References . 7
2.1 Normative references . 7
2.2 Informative references . 8
3 Definition of terms, symbols and abbreviations . 9
3.1 Terms . 9
3.2 Symbols . 9
3.3 Abbreviations . 10
4 Position and Time entity introduction . 11
4.1 Introduction . 11
4.2 Service provided by the PoTi entity . 12
5 PoTi functional description . 12
5.1 PoTi in the ITS Domain . 12
5.2 ITS Constellation . 12
5.3 PoTi in the ITS Station (ITS-S) architecture . 13
5.4 PoTi entity functional architecture . 14
5.4.1 General . 14
5.4.2 Position information Management . 14
5.4.3 Position Augmentation . 15
5.4.4 Reference coordinate System Conversion . 15
5.4.5 Time information Management . 15
5.4.6 Time synchronization . 15
5.4.7 Time reference system conversion Service . 15
5.5 PoTi Interfaces . 16
5.5.1 Interface to ITS applications (FA-SAP). 16
5.5.2 Interfaces to the Networking and Transport Layer (NF-SAP) . 17
5.5.3 Interfaces to the Management entity (MF-SAP) . 17
5.5.4 Interfaces to the Security entity (SF-SAP) . 17
5.5.5 Interfaces to other Facility layer entities . 18
6 Position and time requirements . 18
6.1 Requirements related to PoTi functions . 18
6.2 ITS-S reference position . 20
6.2.1 Introduction. 20
6.2.2 ITS-S reference position for passenger cars . 20
6.2.3 ITS-S reference position for Trucks . 22
6.2.4 ITS-S reference position for Busses . 28
6.2.5 ITS-S reference position for Motorcycles, mopeds and bicycles . 29
6.2.6 ITS-S reference position for Pedestrians . 31
6.2.7 ITS-S reference position for Special Vehicles . 31
6.2.8 ITS-S reference position for City-Tram . 31
6.2.9 ITS-S reference position for Roadside ITS Stations (R-ITS-Ss) . 32
6.3 Position and time confidence. 32
6.3.1 General requirements related to confidence . 32
6.3.2 Confidences related to Position Information Management . 33
6.3.2.1 Horizontal Position confidence . 33
6.3.2.2 Vertical Position confidence . 33
6.3.2.3 Horizontal Speed confidence . 33
6.3.2.4 Heading confidence . 33
ETSI

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SIST EN 302 890-2 V2.1.1:2020
 4 ETSI EN 302 890-2 V2.1.1 (2020-10)
6.3.2.5 Confidence of other quantities . 34
6.3.2.6 Other accuracy estimations . 34
6.3.3 Confidences related to Reference Coordinate System Conversion Management . 34
6.3.3.1 Relative Position confidence . 34
6.3.4 Confidences related to Time Information Management . 34
7 Augmentation services . 35
7.1 Introductions . 35
7.2 GNSS Positioning Correction (GPC) Augmentation Service . 35
7.2.1 Introduction. 35
7.2.2 GPC requirements . 36
7.2.3 GPC Data processing by the V-ITS-S during transition between R-ITS-S service areas . 36
7.3 R-ITS-S ranging augmentation Service . 37
7.3.1 Introduction. 37
7.3.2 Ranging service announcements . 38
7.3.2.1 Introduction . 38
7.3.2.2 Ranging Service Application Data . 39
7.3.3 Measurement. 40
7.3.4 Ranging Rate . 40
7.3.5 Security . 40
Annex A (normative): ASN.1 specification of messages . 41
A.1 ASN.1 specification of ranging service application data . 41
History . 42


ETSI

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SIST EN 302 890-2 V2.1.1:2020
 5 ETSI EN 302 890-2 V2.1.1 (2020-10)
Intellectual Property Rights
Essential patents
IPRs essential or potentially essential to normative deliverables 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 (https://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.
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.
Foreword
This European Standard (EN) has been produced by ETSI Technical Committee Intelligent Transport Systems (ITS).
The present document is part 2 of a multi-part deliverable covering Facilities Layer function, as identified below:
Part 1: "Services Announcement (SA) specification";
Part 2: "Position and Time management (PoTi); Release 2".
The present document is based on inputs provided by various European projects including AutoNet, Concorda,
Ensemble, Hights, PRoPART, Dutch-Germany-Austria Corridor, Scope@F, A58 (NL), PRE-DRIVE C2X, DRIVE
C2X, SafeSpot, CVIS, CoVeL, SCOR@F, simTD, etc.

National transposition dates
Date of adoption of this EN: 19 October 2020
Date of latest announcement of this EN (doa): 31 January 2021
Date of latest publication of new National Standard
or endorsement of this EN (dop/e): 31 July 2021
Date of withdrawal of any conflicting National Standard (dow): 31 July 2021

Modal verbs terminology
In the present document "shall", "shall not", "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.
ETSI

---------------------- Page: 7 ----------------------
SIST EN 302 890-2 V2.1.1:2020
 6 ETSI EN 302 890-2 V2.1.1 (2020-10)
Introduction
Intelligent Transportation Systems Cooperative, Connected and Automated Mobility (CCAM) related use cases in the
ITS environment as specified in the ETSI ITS architecture (ETSI EN 302 665 [i.1]) can be distributed over multiple ITS
stations (ITS-Ss). ITS-Ss interact in the ITS system to exchange sensor data and traffic related information to make each
other aware of traffic safety or traffic efficiency circumstances and situations by which each ITS-S equipped road user,
whether automated or not, can improve their safety and efficiency related decisions.

ETSI

---------------------- Page: 8 ----------------------
SIST EN 302 890-2 V2.1.1:2020
 7 ETSI EN 302 890-2 V2.1.1 (2020-10)
1 Scope
The present document provides the specification of the Position and Time (PoTi) services. It includes functional and
operational requirements for the position and time data to support ITS Applications. In addition, it includes the
definition of syntax and semantics of messages exchanged between ITS Stations (ITS-Ss) to augment the position and
time accuracy. Finally, it specifies the facilities layer protocol in support of such message exchanges.
2 References
2.1 Normative 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.
Referenced documents which are not found to be publicly available in the expected location might be found at
https://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.
The following referenced documents are necessary for the application of the present document.
[1] ETSI TS 103 301: "Intelligent Transport Systems (ITS); Vehicular Communications; Basic Set of
Applications; Facilities layer protocols and communication requirements for infrastructure
services".
[2] RTCM 10402.3: "Recommended Standards for Differential GNSS (Global Navigation Satellite
Systems) Service".
[3] RTCM 10403.3: "Differential GNSS (Global Navigation Satellite Systems) Services - Version 3".
[4] ETSI EN 302 663 (V1.3.1) (01-2020): "Intelligent Transport Systems (ITS); ITS-G5 Access layer
specification for Intelligent Transport Systems operating in the 5 GHz frequency band".
[5] ETSI EN 302 890-1 (V1.2.1) (07-2019): "Intelligent Transport Systems (ITS); Facilities layer
function; Part 1: Services Announcement (SA) specification".
[6] World Geodetic System 1984 (WGS84).
NOTE: Available at http://earth-info.nga.mil/GandG/update/index.php?dir=wgs84&action=wgs84#tab_wgs84-
res.
[7] ISO 8855 (2011): "Road Vehicles -- Vehicle dynamics and road-holding ability -- Vocabulary".
[8] ETSI TS 103 248: "Intelligent Transport Systems (ITS); GeoNetworking; Port Numbers for the
Basic Transport Protocol (BTP)".
[9] ISO 5725-1 (1994): "Accuracy (trueness and precision) of measurement methods and results --
Part 1: General principles and definitions".
[10] ETSI TS 102 894-2: "Intelligent Transport Systems (ITS); Users and applications requirements;
Part 2: Applications and facilities layer common data dictionary".
[11] ETSI EN 302 931 (V1.1.1): "Intelligent Transport Systems (ITS); Vehicular Communications;
Geographical Area Definition".
[12] ISO/TS 16460:2016: "Intelligent transport systems -- Communications access for land mobiles
(CALM) -- Communication protocol messages for global usage".
ETSI

---------------------- Page: 9 ----------------------
SIST EN 302 890-2 V2.1.1:2020
 8 ETSI EN 302 890-2 V2.1.1 (2020-10)
[13] Recommendation ITU-T X.691/ISO/IEC 8825-2:2015: "Information technology - ASN.1 encoding
rules: Specification of Packed Encoding Rules (PER)".
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 with regard to a particular subject area.
[i.1] ETSI EN 302 665: "Intelligent Transport Systems (ITS); Communications Architecture".
[i.2] ETSI TR 102 638 (V1.1.1): "Intelligent Transport Systems (ITS); Vehicular Communications;
Basic Set of Applications; Definitions".
[i.3] ETSI EN 302 637-2: "Intelligent Transport Systems (ITS); Vehicular Communications; Basic Set
of Applications; Part 2: Specification of Cooperative Awareness Basic Service".
[i.4] ETSI EN 302 637-3: "Intelligent Transport Systems (ITS); Vehicular Communications; Basic Set
of Applications; Part 3: Specifications of Decentralized Environmental Notification Basic
Service".
[i.5] ETSI TS 102 894-1 (V1.1.1): "Intelligent Transport Systems (ITS); Users and applications
requirements; Part 1: Facility layer structure, functional requirements and specifications".
[i.6] ETSI TR 103 299: "Intelligent Transport System (ITS); Cooperative Adaptive Cruise Control
(CACC); Pre-standardization study".
[i.7] ETSI TS 103 324: "Intelligent Transport Systems (ITS); Cooperative Perception Services".
[i.8] ETSI TS 103 246-1 (V1.2.1) (03-2017): "Satellite Earth Stations and Systems (SES); GNSS based
location systems; Part 1: Functional requirements".
[i.9] EUREF: "European Terrestrial Reference System 89 (ETRS89)".
NOTE: Available at http://etrs89.ensg.ign.fr.
[i.10] ETSI TR 101 607 (V1.1.1) (05-2013): "Intelligent Transport Systems (ITS); Cooperative ITS
(C-ITS); Release 1".
[i.11] ISO 3534-1 (10-2009): "Statistics - Vocabulary and symbols - Part 1: General statistical terms and
terms".
[i.12] ETSI TS 136 305 (V11.2.0): "LTE; Evolved Universal Terrestrial Radio Access Network
(E-UTRAN); Stage 2 functional specification of User Equipment (UE) positioning in E-UTRAN
(3GPP TS 36.305 version 11.2.0 Release 11)".
[i.13] IETF RFC 5905 (June 2010): "Network Time Protocol Version 4: Protocol and Algorithms
Specification".
[i.14] IEC 60050: "International Electrotechnical Vocabulary", 113-01-08 (instant), 113-01-10 (time
interval), 113-01-13 (duration).
[i.15] IS-QZSS-L6-001: "Quasi-Zenith Satellite System Interface Specification Centimeter Level
Augmentation Service".
NOTE: Available at https://qzss.go.jp/en/technical/download/pdf/ps-is-qzss/is-qzss-l6-001.pdf.
[i.16] IETF RFC 8173 (June 2017): "Precision Time Protocol Version 2 (PTPv2) Management
Information Base".
ETSI

---------------------- Page: 10 ----------------------
SIST EN 302 890-2 V2.1.1:2020
 9 ETSI EN 302 890-2 V2.1.1 (2020-10)
[i.17] EN ISO 22418: "Intelligent transport systems - Fast service announcement protocol (FSAP) for
general purposes in ITS" (produced by CEN).
TM
1609.3: "IEEE Standard for Wireless Access in Vehicular Environments (WAVE) --
[i.18] IEEE
Networking Services".
3 Definition of terms, symbols and abbreviations
3.1 Terms
For the purposes of the present document, the following terms apply:
accuracy: closeness of a measured value to a standard or known value
heading: orientation of the horizontal velocity vector with respect to the WGS84 [6] North (clockwise), unless
otherwise noted
horizontal speed: magnitude of horizontal velocity-vector of the reference position point
horizontal velocity vector: projection of the 3D velocity vector on the WGS84 [6] ellipsoid
integrity risk: probability, per unit of time, of having a Parameter Failure without issuing an alert within the
Time-to-Alert
ITS constellation: group of ITS-Ss which are exchanging ITS data among themselves
ITS time: time based on TAI
st
NOTE: Epoch of this time is set to 2004-01-01T00:00:00Z, that is 0 seconds on 1 of January 2004 UTC.
parameter failure: failure occurring when the position and time entity is unable to estimate parameters with an error
less than the maximum tolerable error (err > err_max)
position integrity: measure of the trust that can be placed in the correctness of the estimated Parameters supplied by the
Position and Time entity
NOTE: Integrity includes the ability of the equipment (at the Position and Time entity and/or User level) to
compute timely and valid alerts when the estimated Parameters do not need to be used for the operation of
interest.
protection level: estimated bound on the Parameter Error from the Position and Time entity at a defined confidence
level such as 50 %, 75 %, 95 %, 99 %, etc., delivered with the Parameters
station clock: clock representing ITS time in an ITS Station
Time-to-Alert: maximum allowable elapsed time from the onset of a Parameter Failure until the equipment annunciates
the alert
velocity: vector indicating speed in a particular direction
vertical velocity vector: projection of the 3D velocity vector on the normal vector of the WGS84 [6] Ellipsoid
3.2 Symbols
For the purposes of the present document, the following symbols apply:
Tsys ITS Station Time
ETSI

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SIST EN 302 890-2 V2.1.1:2020
 10 ETSI EN 302 890-2 V2.1.1 (2020-10)
3.3 Abbreviations
For the purposes of the present document, the following abbreviations apply:
3D 3 Dimensional
ACC Automatic Crouse Control
ACK Acknowledgement
ASN Abstract Syntax Notation
BSA Basic Set of Applications
CA Cooperative Awareness (service)
CACC Cooperative Adaptive Cruise Control
CAM Cooperative Awareness Message
CCAM Cooperative, Connected and Automated Mobility
CDD Common Data Dictionary
CP Collective Perception (service)
CVIS Cooperative Vehicle-Infrastructure Systems
DEN Decentralized Environmental Notification
DENM Decentralized Environmental Notification Message
D-GNSS Differential Global Navigation Satellite System
ECU Electronic Control Unit
EDAS EGNOS Data Access Service
EGNOS European Geostationary Navigation Overlay Service
EU European Union
FA-SAP Facilities to Applications Service Access Point
GLONASS GLObal NAvigation Satellite System
GNSS Global Navigation Satellite Systems
GPC GNSS Positioning Correction
GPS Global Positioning System
GRM GPS Raw data Message
IEC International Electrotechnical Commission
IETF Internet Engineering Task Force
ISO International Organization for Standardization
ITRF International Terrestrial Reference Frame
ITS Intelligent Transport Systems
ITS-C ITS Constellation
ITS-S ITS Station
ITU-T International Telecommunication Union - Telecommunication standardization sector
MAC Media Access Control
NA Not Applicable
NF-SAP Network to Facilities Service Access Point
NGA National Geospatial-intelligence Agency
NRTK Network Real Time Kinematic
NTP Network Time Protocol
PDU Protocol Data Unit
PoTi Position and Time
PPP Precise Point Positioning
PSID Provider Service Identifier
RAN Radio Access Network
RF Radio Frequency
RFC Request For Comment
R-ITS-S Roadside ITS Station
RTCM Radio Technical Commission for Maritime services
RTCMEM Radio Technical Commission for Maritime services Environmental Message
RTK Real Time Kinematic
SA Service Announcement
SAM Service Announcement Message
SF-SAP Security to Facilities Service Access Point
SI Standard International
SIFS Short InterFrame Space
SLR Satellite Laser Ranging
SPATEM Signal Phase And Timing Extended Message
ETSI

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SIST EN 302 890-2 V2.1.1:2020
 11 ETSI EN 302 890-2 V2.1.1 (2020-10)
SSR Sirius Satellite Radio
TAI International Atomic Time scale
TCU Transmission Control Unit
ToF Time-of-Flight
UE User Equipment
UPER Unaligned Packet Encoding Rules
UTC Coordinated Univer
...

Final draft ETSI EN 302 890-2 V2.1.1 (2020-08)






EUROPEAN STANDARD
Intelligent Transport Systems (ITS);
Facilities Layer function;
Part 2: Position and Time management (PoTi);
Release 2

---------------------- Page: 1 ----------------------
2 Final draft ETSI EN 302 890-2 V2.1.1 (2020-08)



Reference
DEN/ITS-00182
Keywords
facility, ITS, time-stamping

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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
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of the oneM2M Partners.
®
GSM and the GSM logo are trademarks registered and owned by the GSM Association.
ETSI

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3 Final draft ETSI EN 302 890-2 V2.1.1 (2020-08)
Contents
Intellectual Property Rights . 5
Foreword . 5
Modal verbs terminology . 5
Introduction . 6
1 Scope . 7
2 References . 7
2.1 Normative references . 7
2.2 Informative references . 8
3 Definition of terms, symbols and abbreviations . 9
3.1 Terms . 9
3.2 Symbols . 9
3.3 Abbreviations . 10
4 Position and Time entity introduction . 11
4.1 Introduction . 11
4.2 Service provided by the PoTi entity . 12
5 PoTi functional description . 12
5.1 PoTi in the ITS Domain . 12
5.2 ITS Constellation . 12
5.3 PoTi in the ITS Station (ITS-S) architecture . 13
hitecture . 14
5.4 PoTi entity functional arc
5.4.1 General . 14
5.4.2 Position information Management . 14
5.4.3 Position Augmentation . 15
5.4.4 Reference coordinate System Conversion . 15
5.4.5 Time information Management . 15
5.4.6 Time synchronization . 15
5.4.7 Time reference system conversion Service . 15
5.5 PoTi Interfaces . 16
5.5.1 Interface to ITS applications (FA-SAP). 16
5.5.2 Interfaces to the Networking and Transport Layer (NF-SAP) . 17
5.5.3 Interfaces to the Management entity (MF-SAP) . 17
5.5.4 Interfaces to the Security entity (SF-SAP) . 17
5.5.5 Interfaces to other Facility layer entities . 18
6 Position and time requirements . 18
6.1 Requirements related to PoTi functions . 18
6.2 ITS-S reference position . 20
6.2.1 Introduction. 20
6.2.2 ITS-S reference position for passenger cars . 20
6.2.3 ITS-S reference position for Trucks . 22
6.2.4 ITS-S reference position for Busses . 28
6.2.5 ITS-S reference position for Motorcycles, mopeds and bicycles . 29
6.2.6 ITS-S reference position for Pedestrians . 31
6.2.7 ITS-S reference position for Special Vehicles . 31
6.2.8 ITS-S reference position for City-Tram . 31
6.2.9 ITS-S reference position for Roadside ITS Stations (R-ITS-Ss) . 32
6.3 Position and time confidence. 32
6.3.1 General requirements related to confidence . 32
6.3.2 Confidences related to Position Information Management . 33
6.3.2.1 Horizontal Position confidence . 33
6.3.2.2 Vertical Position confidence . 33
6.3.2.3 Horizontal Speed confidence . 33
6.3.2.4 Heading confidence . 33
ETSI

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4 Final draft ETSI EN 302 890-2 V2.1.1 (2020-08)
6.3.2.5 Confidence of other quantities . 34
6.3.2.6 Other accuracy estimations . 34
6.3.3 Confidences related to Reference Coordinate System Conversion Management . 34
6.3.3.1 Relative Position confidence . 34
6.3.4 Confidences related to Time Information Management . 34
7 Augmentation services . 35
7.1 Introductions . 35
7.2 GNSS Positioning Correction (GPC) Augmentation Service . 35
7.2.1 Introduction. 35
7.2.2 GPC requirements . 36
7.2.3 GPC Data processing by the V-ITS-S during transition between R-ITS-S service areas . 36
7.3 R-ITS-S ranging augmentation Service . 37
7.3.1 Introduction. 37
7.3.2 Ranging service announcements . 38
7.3.2.1 Introduction . 38
7.3.2.2 Ranging Service Application Data . 39
7.3.3 Measurement. 40
7.3.4 Ranging Rate . 40
7.3.5 Security . 40
Annex A (normative): ASN.1 specification of messages . 41
A.1 ASN.1 specification of ranging service application data . 41
History . 42
ETSI

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5 Final draft ETSI EN 302 890-2 V2.1.1 (2020-08)
Intellectual Property Rights
Essential patents
IPRs essential or potentially essential to normative deliverables 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 (https://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.
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.
Foreword
This final draft European Standard (EN) has been produced by ETSI Technical Committee Intelligent Transport
Systems (ITS), and is now submitted for the Vote phase of the ETSI standards EN Approval Procedure.
The present document is part 2 of a multi-part deliverable covering Facilities Layer function, as identified below:
Part 1: "Services Announcement (SA) specification";
Part 2: "Position and Time management (PoTi); Release 2".
The present document is based on inputs provided by various European projects including AutoNet, Concorda,
Ensemble, Hights, PRoPART, Dutch-Germany-Austria Corridor, Scope@F, A58 (NL), PRE-DRIVE C2X, DRIVE
C2X, SafeSpot, CVIS, CoVeL, SCOR@F, simTD, etc.
Proposed national transposition dates
Date of latest announcement of this EN (doa): 3 months after ETSI publication
Date of latest publication of new National Standard
or endorsement of this EN (dop/e): 6 months after doa
Date of withdrawal of any conflicting National Standard (dow): 6 months after doa
Modal verbs terminology
In the present document "shall", "shall not", "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.
ETSI

---------------------- Page: 5 ----------------------
6 Final draft ETSI EN 302 890-2 V2.1.1 (2020-08)
Introduction
Intelligent Transportation Systems Cooperative, Connected and Automated Mobility (CCAM) related use cases in the
ITS environment as specified in the ETSI ITS architecture (ETSI EN 302 665 [i.1]) can be distributed over multiple ITS
stations (ITS-Ss). ITS-Ss interact in the ITS system to exchange sensor data and traffic related information to make each
other aware of traffic safety or traffic efficiency circumstances and situations by which each ITS-S equipped road user,
whether automated or not, can improve their safety and efficiency related decisions.
ETSI

---------------------- Page: 6 ----------------------
7 Final draft ETSI EN 302 890-2 V2.1.1 (2020-08)
1 Scope
The present document provides the specification of the Position and Time (PoTi) services. It includes functional and
operational requirements for the position and time data to support ITS Applications. In addition, it includes the
definition of syntax and semantics of messages exchanged between ITS Stations (ITS-Ss) to augment the position and
time accuracy. Finally, it specifies the facilities layer protocol in support of such message exchanges.
2 References
2.1 Normative 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.
Referenced documents which are not found to be publicly available in the expected location might be found at
https://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.
The following referenced documents are necessary for the application of the present document.
[1] ETSI TS 103 301: "Intelligent Transport Systems (ITS); Vehicular Communications; Basic Set of
Applications; Facilities layer protocols and communication requirements for infrastructure
services".
[2] RTCM 10402.3: "Recommended Standards for Differential GNSS (Global Navigation Satellite
Systems) Service".
[3] RTCM 10403.3: "Differential GNSS (Global Navigation Satellite Systems) Services - Version 3".
[4] ETSI EN 302 663 (V1.3.1) (01-2020): "Intelligent Transport Systems (ITS); ITS-G5 Access layer
specification for Intelligent Transport Systems operating in the 5 GHz frequency band".
[5] ETSI EN 302 890-1 (V1.2.1) (07-2019): "Intelligent Transport Systems (ITS); Facilities layer
function; Part 1: Services Announcement (SA) specification".
[6] World Geodetic System 1984 (WGS84).
NOTE: Available at http://earth-info.nga.mil/GandG/update/index.php?dir=wgs84&action=wgs84#tab_wgs84-
res.
[7] ISO 8855 (2011): "Road Vehicles -- Vehicle dynamics and road-holding ability -- Vocabulary".
[8] ETSI TS 103 248: "Intelligent Transport Systems (ITS); GeoNetworking; Port Numbers for the
Basic Transport Protocol (BTP)".
[9] ISO 5725-1 (1994): "Accuracy (trueness and precision) of measurement methods and results --
Part 1: General principles and definitions".
[10] ETSI TS 102 894-2: "Intelligent Transport Systems (ITS); Users and applications requirements;
Part 2: Applications and facilities layer common data dictionary".
[11] ETSI EN 302 931 (V1.1.1): "Intelligent Transport Systems (ITS); Vehicular Communications;
Geographical Area Definition".
[12] ISO/TS 16460:2016: "Intelligent transport systems -- Communications access for land mobiles
(CALM) -- Communication protocol messages for global usage".
ETSI

---------------------- Page: 7 ----------------------
8 Final draft ETSI EN 302 890-2 V2.1.1 (2020-08)
[13] Recommendation ITU-T X.691/ISO/IEC 8825-2:2015: "Information technology - ASN.1 encoding
rules: Specification of Packed Encoding Rules (PER)".
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 with regard to a particular subject area.
[i.1] ETSI EN 302 665: "Intelligent Transport Systems (ITS); Communications Architecture".
[i.2] ETSI TR 102 638 (V1.1.1): "Intelligent Transport Systems (ITS); Vehicular Communications;
Basic Set of Applications; Definitions".
[i.3] ETSI EN 302 637-2: "Intelligent Transport Systems (ITS); Vehicular Communications; Basic Set
of Applications; Part 2: Specification of Cooperative Awareness Basic Service".
[i.4] ETSI EN 302 637-3: "Intelligent Transport Systems (ITS); Vehicular Communications; Basic Set
of Applications; Part 3: Specifications of Decentralized Environmental Notification Basic
Service".
[i.5] ETSI TS 102 894-1 (V1.1.1): "Intelligent Transport Systems (ITS); Users and applications
requirements; Part 1: Facility layer structure, functional requirements and specifications".
[i.6] ETSI TR 103 299: "Intelligent Transport System (ITS); Cooperative Adaptive Cruise Control
(CACC); Pre-standardization study".
[i.7] ETSI TS 103 324: "Intelligent Transport Systems (ITS); Cooperative Perception Services".
[i.8] ETSI TS 103 246-1 (V1.2.1) (03-2017): "Satellite Earth Stations and Systems (SES); GNSS based
location systems; Part 1: Functional requirements".
[i.9] EUREF: European Terrestrial Reference System 89 (ETRS89).
NOTE: Available at http://etrs89.ensg.ign.fr.
[i.10] ETSI TR 101 607 (V1.1.1) (05-2013): "Intelligent Transport Systems (ITS); Cooperative ITS
(C-ITS); Release 1".
[i.11] ISO 3534-1 (10-2009): "Statistics - Vocabulary and symbols - Part 1: General statistical terms and
terms".
[i.12] ETSI TS 136 305 (V11.2.0): "LTE; Evolved Universal Terrestrial Radio Access Network (E-
UTRAN); Stage 2 functional specification of User Equipment (UE) positioning in E-UTRAN
(3GPP TS 36.305 version 11.2.0 Release 11)".
[i.13] IETF RFC 5905 (June 2010): "Network Time Protocol Version 4: Protocol and Algorithms
Specification".
[i.14] IEC 60050: "International Electrotechnical Vocabulary", 113-01-08 (instant), 113-01-10 (time
interval), 113-01-13 (duration).
[i.15] IS-QZSS-L6-001: "Quasi-Zenith Satellite System Interface Specification Centimeter Level
Augmentation Service".
NOTE: Available at https://qzss.go.jp/en/technical/download/pdf/ps-is-qzss/is-qzss-l6-001.pdf.
[i.16] IETF RFC 8173 (June 2017): "Precision Time Protocol Version 2 (PTPv2) Management
Information Base".
ETSI

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9 Final draft ETSI EN 302 890-2 V2.1.1 (2020-08)
[i.17] EN ISO 22418: "Intelligent transport systems - Fast service announcement protocol (FSAP) for
general purposes in ITS" (produced by CEN).
TM
1609.3: "IEEE Standard for Wireless Access in Vehicular Environments (WAVE) --
[i.18] IEEE
Networking Services".
3 Definition of terms, symbols and abbreviations
3.1 Terms
For the purposes of the present document, the following terms apply:
accuracy: closeness of a measured value to a standard or known value
heading: orientation of the horizontal velocity vector with respect to the WGS84 [6] North (clockwise), unless
otherwise noted
horizontal speed: magnitude of horizontal velocity-vector of the reference position point
horizontal velocity vector: projection of the 3D velocity vector on the WGS84 [6] ellipsoid
integrity risk: probability, per unit of time, of having a Parameter Failure without issuing an alert within the
Time-to-Alert
ITS constellation: group of ITS-Ss which are exchanging ITS data among themselves
ITS time: time based on TAI
st
NOTE: Epoch of this time is set to 2004-01-01T00:00:00Z, that is 0 seconds on 1 of January 2004 UTC.
parameter failure: failure occurring when the position and time entity is unable to estimate parameters with an error
less than the maximum tolerable error (err > err_max)
position integrity: measure of the trust that can be placed in the correctness of the estimated Parameters supplied by the
Position and Time entity
NOTE: Integrity includes the ability of the equipment (at the Position and Time entity and/or User level) to
compute timely and valid alerts when the estimated Parameters do not need to be used for the operation of
interest.
protection level: estimated bound on the Parameter Error from the Position and Time entity at a defined confidence
level such as 50 %, 75 %, 95 %, 99 %, etc., delivered with the Parameters
station clock: clock representing ITS time in an ITS Station
Time-to-Alert: maximum allowable elapsed time from the onset of a Parameter Failure until the equipment annunciates
the alert
velocity: vector indicating speed in a particular direction
vertical velocity vector: projection of the 3D velocity vector on the normal vector of the WGS84 [6] Ellipsoid
3.2 Symbols
For the purposes of the present document, the following symbols apply:
Tsys ITS Station Time
ETSI

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10 Final draft ETSI EN 302 890-2 V2.1.1 (2020-08)
3.3 Abbreviations
For the purposes of the present document, the following abbreviations apply:
3D 3 Dimensional
ACC Automatic Crouse Control
ACK Acknowledgement
ASN Abstract Syntax Notation
BSA Basic Set of Applications
CA Cooperative Awareness (service)
CACC Cooperative Adaptive Cruise Control
CAM Cooperative Awareness Message
CCAM Cooperative, Connected and Automated Mobility
CDD Common Data Dictionary
CP Collective Perception (service)
CVIS Cooperative Vehicle-Infrastructure Systems
DEN Decentralized Environmental Notification
DENM Decentralized Environmental Notification Message
D-GNSS Differential Global Navigation Satellite System
ECU Electronic Control Unit
EDAS EGNOS Data Access Service
EGNOS European Geostationary Navigation Overlay Service
EU European Union
FA-SAP Facilities to Applications Service Access Point
GLONASS GLObal NAvigation Satellite System
GNSS Global Navigation Satellite Systems
GPC GNSS Positioning Correction
GPS Global Positioning System
GRM GPS Raw data Message
IEC International Electrotechnical Commission
IETF Internet Engineering Task Force
ISO International Organization for Standardization
ITRF International Terrestrial Reference Frame
ITS Intelligent Transport Systems
ITS-C ITS Constellation
ITS-S ITS Station
ITU-T International Telecommunication Union - Telecommunication standardization sector
MAC Media Access Control
NA Not Applicable
NF-SAP Network to Facilities Service Access Point
NGA National Geospatial-intelligence Agency
NRTK Network Real Time Kinematic
NTP Network Time Protocol
PDU Protocol Data Unit
PoTi Position and Time
PPP Precise Point Positioning
PSID Provider Service Identifier
RAN Radio Access Network
RF Radio Frequency
RFC Request For Comment
R-ITS-S Roadside ITS Station
RTCM Radio Technical Commission for Maritime services
RTCMEM Radio Technical Commission for Maritime services Environmental Message
RTK Real Time Kinematic
SA Service Announcement
SAM Service Announcement Message
SF-SAP Security to Facilities Service Access Point
SI Standard International
SIFS Short InterFrame Space
SLR Satellite Laser Ranging
SPATEM Signal Phase And Timing Extended Message
ETSI

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11 Final draft ETSI EN 302 890-2 V2.1.1 (2020-08)
SSR Sirius Satellite Radio
TAI International Atomic Time scale
TCU Transmission Control Unit
ToF Time-of-Flight
UE User Equipment
UPER Unaligned Packet Encoding Rules
UTC Coordinated Universal Time
UWB Ultra Wide Band
VLBI Very-Long-Baseline Interferometry
VRU Vulnerable Road User
WGS World Geodetic System
WGS84 World Geodetic System 1984
4 Position and Time entity introduction
4.1 Introduction
ITS applications such as specified in the Basic Set of Applications specification (BSA) ETSI TR 102 638 [i.2] require
the exchange of position and time information as part of the information exchange among ITS-Ss. As initial ITS
location based services, the Cooperative Awareness (CA) basic service ETSI EN 302 637-2 [i.3] and similar, the road
traffic event Decentralized Environmental Notification (DEN) basic service ETSI EN 302 637-3 [i.4] are developed.
These services and their data exchanges are dependent on position and time information. In this and the following
clauses it is understood that "position" means kinematic and attitude state as defined in clause 5.4.1 which includes
attitude and movement parameters including velocity, heading,
...

Draft ETSI EN 302 890-2 V2.1.1 (2020-03)






EUROPEAN STANDARD
Intelligent Transport Systems (ITS);
Facilities Layer function;
Part 2: Position and Time management (PoTi);
Release 2

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2 Draft ETSI EN 302 890-2 V2.1.1 (2020-03)



Reference
DEN/ITS-00182
Keywords
facility, ITS, time-stamping

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
The present document can be downloaded from:
http://www.etsi.org/standards-search
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No part may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying
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The copyright and the foregoing restriction extend to reproduction in all media.

© ETSI 2020.
All rights reserved.

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
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®
GSM and the GSM logo are trademarks registered and owned by the GSM Association.
ETSI

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3 Draft ETSI EN 302 890-2 V2.1.1 (2020-03)
Contents
Intellectual Property Rights . 5
Foreword . 5
Modal verbs terminology . 5
Introduction . 6
1 Scope . 7
2 References . 7
2.1 Normative references . 7
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 Position and Time entity introduction . 11
4.1 Introduction . 11
4.2 Service provided by the PoTi entity . 11
5 PoTi functional description . 12
5.1 PoTi in the ITS Domain . 12
5.2 ITS Constellation . 12
5.3 PoTi in the ITS Station (ITS-S) architecture . 13
5.4 PoTi entity functional architecture . 14
5.4.1 General . 14
5.4.2 Position information Management . 14
5.4.3 Position Augmentation . 15
5.4.4 Reference coordinate System Conversion . 15
5.4.5 Time information Management . 15
5.4.6 Time synchronization . 15
5.4.7 Time reference system conversion Service . 15
5.5 PoTi Interfaces . 16
5.5.1 Interface to ITS applications (FA-SAP). 16
5.5.2 Interfaces to the Networking and Transport Layer (NF-SAP) . 17
5.5.3 Interfaces to the Management entity (MF-SAP) . 17
5.5.4 Interfaces to the Security entity (SF-SAP) . 17
5.5.5 Interfaces to other Facility layer entities . 18
6 Position and time requirements . 18
6.1 Requirements related to PoTi functions . 18
6.2 ITS-S reference position . 20
6.2.1 Introduction. 20
6.2.2 ITS-S reference position for passenger cars . 20
6.2.3 ITS-S reference position for Trucks . 22
6.2.4 ITS-S reference position for Busses . 28
6.2.5 ITS-S reference position for Motorcycles, mopeds and bicycles . 29
6.2.6 ITS-S reference position for Pedestrians . 31
6.2.7 ITS-S reference position for Special Vehicles . 31
6.2.8 ITS-S reference position for City-Tram . 31
6.2.9 ITS-S reference position for Roadside ITS Stations (R-ITS-S's) . 32
6.3 Position and time confidence. 32
6.3.1 General requirements related to confidence . 32
6.3.2 Confidences related to Position Information Management . 33
6.3.2.1 Horizontal Position confidence . 33
6.3.2.2 Vertical Position confidence . 33
6.3.2.3 Horizontal Speed confidence . 33
6.3.2.4 Heading confidence . 33
ETSI

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4 Draft ETSI EN 302 890-2 V2.1.1 (2020-03)
6.3.2.5 Confidence of other quantities . 34
6.3.2.6 Other accuracy estimations . 34
6.3.3 Confidences related to Reference Coordinate System Conversion Management . 34
6.3.3.1 Relative Position confidence . 34
6.3.4 Confidences related to Time Information Management . 34
7 Augmentation services . 34
7.1 Introductions . 34
7.2 GNSS Positioning Correction (GPC) Augmentation Service . 35
7.2.1 Introduction. 35
7.2.2 GPC requirements . 35
7.2.3 GPC Data exchange between R-ITS-S's . 36
7.3 R-ITS-S ranging augmentation Service . 37
7.3.1 Introduction. 37
7.3.2 Ranging service announcements . 38
7.3.2.1 Introduction . 38
7.3.2.2 Ranging Service Application Data . 38
7.3.3 Measurement. 39
7.3.4 Ranging Rate . 40
7.3.5 Security . 40
Annex A (normative): ASN.1 specification of messages . 41
A.1 ASN.1 specification of ranging service application data . 41
History . 42


ETSI

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5 Draft ETSI EN 302 890-2 V2.1.1 (2020-03)
Intellectual Property Rights
Essential patents
IPRs essential or potentially essential to normative deliverables 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 (https://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.
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.
Foreword
This draft European Standard (EN) has been produced by ETSI Technical Committee Intelligent Transport Systems
(ITS), and is now submitted for the combined Public Enquiry and Vote phase of the ETSI standards EN Approval
Procedure.
The present document is part 2 of a multi-part deliverable covering Facilities Layer function, as identified below:
Part 1: "Services Announcement (SA) specification";
Part 2: "Position and Time management (PoTi)".
The present document is based on inputs provided by various European projects including AutoNet, Concorda,
Ensemble, Hights, PRoPART, Dutch-Germany-Austria Corridor, Scope@F, A58 (NL), PRE-DRIVE C2X, DRIVE
C2X, SafeSpot, CVIS, CoVeL, SCOR@F, simTD, etc.

Proposed national transposition dates
Date of latest announcement of this EN (doa): 3 months after ETSI publication
Date of latest publication of new National Standard
or endorsement of this EN (dop/e): 6 months after doa
Date of withdrawal of any conflicting National Standard (dow): 6 months after doa

Modal verbs terminology
In the present document "shall", "shall not", "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.
ETSI

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6 Draft ETSI EN 302 890-2 V2.1.1 (2020-03)
Introduction
Intelligent Transportation Systems Cooperative, Connected and Automated Mobility(CCAM) related use cases in the
ITS environment as specified in the ETSI ITS architecture (ETSI EN 302 665 [i.1]) can be distributed over multiple ITS
stations (ITS-S's). ITS-S's interact in the ITS system to exchange sensor data and traffic related information to make
each other aware of traffic safety or traffic efficiency circumstances and situations by which each ITS-S equipped road
user, whether automated or not, can improve their safety and efficiency related decisions.

ETSI

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7 Draft ETSI EN 302 890-2 V2.1.1 (2020-03)
1 Scope
The present document provides the specification of the Position and Time (PoTi) services. It includes functional and
operational requirements for the position and time data to support ITS Applications. In addition, it includes the
definition of syntax and semantics of messages exchanged between ITS-Stations (ITS-Ss) to augment the position and
time accuracy. Finally, it specifies the facilities layer protocol in support of such message exchanges.
2 References
2.1 Normative 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.
Referenced documents which are not found to be publicly available in the expected location might be found at
https://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.
The following referenced documents are necessary for the application of the present document.
[1] ETSI TS 103 301: "Intelligent Transport Systems (ITS); Vehicular Communications; Basic Set of
Applications; Facilities layer protocols and communication requirements for infrastructure
services".
[2] RTCM 10402.3: "Recommended Standards for Differential GNSS (Global Navigation Satellite
Systems) Service".
[3] RTCM 10403.3: "Differential GNSS (Global Navigation Satellite Systems) Services - Version 3".
[4] ETSI EN 302 663 (V1.3.1) (2020-01): "Intelligent Transport Systems (ITS); ITS-G5 Access layer
specification for Intelligent Transport Systems operating in the 5 GHz frequency band".
[5] ETSI EN 302 890-1 (V1.2.1) (2019-07): "Intelligent Transport Systems (ITS); Facilities layer
function; Part 1: Services Announcement (SA) specification".
[6] World Geodetic System 84 (WGS84).
NOTE: Available at http://earth-info.nga.mil/GandG/update/index.php?dir=wgs84&action=wgs84#tab_wgs84-
res.
[7] ISO 8855 (2011): "Road Vehicles -- Vehicle dynamics and road-holding ability -- Vocabulary".
[8] ETSI TS 103 248: "Intelligent Transport Systems (ITS); GeoNetworking; Port Numbers for the
Basic Transport Protocol (BTP)".
[9] ISO 5725-1 (1994), "Accuracy (trueness and precision) of measurement methods and results --
Part 1: General principles and definitions".
[10] ETSI TS 102 894-2: "Intelligent Transport Systems (ITS); Users and applications requirements;
Part 2: Applications and facilities layer common data dictionary".
[11] ETSI EN 302 931 (V1.1.1): "Intelligent Transport Systems (ITS); Vehicular Communications;
Geographical Area Definition".
ETSI

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8 Draft ETSI EN 302 890-2 V2.1.1 (2020-03)
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 with regard to a particular subject area.
[i.1] ETSI EN 302 665: "Intelligent Transport Systems (ITS); Communications Architecture".
[i.2] ETSI TR 102 638 (V1.1.1): "Intelligent Transport Systems (ITS); Vehicular Communications;
Basic Set of Applications; Definitions".
[i.3] ETSI EN 302 637-2: "Intelligent Transport Systems (ITS); Vehicular Communications; Basic Set
of Applications; Part 2: Specification of Cooperative Awareness Basic Service".
[i.4] ETSI EN 302 637-3: "Intelligent Transport Systems (ITS); Vehicular Communications; Basic Set
of Applications; Part 3: Specifications of Decentralized Environmental Notification Basic
Service".
[i.5] ETSI TS 102 894-1 (V1.1.1): "Intelligent Transport Systems (ITS); Users and applications
requirements; Part 1: Facility layer structure, functional requirements and specifications".
[i.6] ETSI TR 103 299: "Intelligent Transport System (ITS); Cooperative Adaptive Cruise Control
(CACC); Pre-standardization study".
[i.7] ETSI TS 103 324: "Intelligent Transport Systems (ITS); Cooperative Perception Services".
[i.8] ETSI TS 103 246-1 (V1.2.1) (2017-03): "Satellite Earth Stations and Systems (SES); GNSS based
location systems; Part 1: Functional requirements".
[i.9] EUREF, European Terrestrial Reference System (ETRS89).
NOTE: Available at http://etrs89.ensg.ign.fr.
[i.10] ETSI TR 101 607 (V1.1.1) (2013-05): "Intelligent Transport Systems (ITS); Cooperative ITS
(C-ITS); Release 1".
[i.11] ISO 3534-1 (2009-10): "Statistics - Vocabulary and symbols - Part 1: General statistical terms and
terms".
[i.12] ETSI TS 136 305 (V11.2.0): "LTE; Evolved Universal Terrestrial Radio Access Network (E-
UTRAN); Stage 2 functional specification of User Equipment (UE) positioning in E-UTRAN
(3GPP TS 36.305 version 11.2.0 Release 11)".
[i.13] IETF RFC 5905 (June 2010): "Network Time Protocol Version 4: Protocol and Algorithms
Specification".
[i.14] IEC 60050: "International Electrotechnical Vocabulary", 113-01-08 (instant), 113-01-10 (time
interval), 113-01-13 (duration).
[i.15] Quasi-Zenith Satellite System Interface Specification Centimeter Level Augmentation Service (IS
-QZSSQZSS -L6 -00 1).
NOTE: Available at https://qzss.go.jp/en/technical/download/pdf/ps-is-qzss/is-qzss-l6-001.pdf.
[i.16] IETF RFC 8173 (June 2017): "Precision Time Protocol Version 2 (PTPv2) Management
Information Base".
ETSI

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9 Draft ETSI EN 302 890-2 V2.1.1 (2020-03)
3 Definition of terms, symbols and abbreviations
3.1 Terms
For the purposes of the present document, the following terms apply:
accuracy: closeness of a measured value to a standard or known value
heading: orientation of the horizontal velocity vector with respect to the WGS84 [6] North (clockwise), unless
otherwise noted
horizontal speed: magnitude of horizontal velocity-vector of the reference position point
horizontal velocity vector: projection of the 3D velocity vector on the WGS84 [6] ellipsoid
integrity risk: probability, per unit of time, of having a Parameter Failure without issuing an alert within the
Time-to-Alert
ITS constellation: group of ITS-S's which are exchanging ITS data among themselves
ITS time: time based on TAI
st
NOTE: Epoch of this time is set to 2004-01-01T00:00:00Z, that is 0 seconds on 1 of January 2004 UTC.
parameter failure: failure occurring when the position and time entity is unable to estimate parameters with an error
less than the maximum tolerable error (err > err_max)
position integrity: measure of the trust that can be placed in the correctness of the estimated Parameters supplied by the
Position and Time entity
NOTE: Integrity includes the ability of the equipment (at the Position and Time entity and/or User level) to
compute timely and valid alerts when the estimated Parameters do not need to be used for the operation of
interest.
protection level: estimated bound on the Parameter Error from the Position and Time entity at a defined confidence
level such as 50 %, 75 %, 95 %, 99 %, etc., delivered with the Parameters
station clock: clock representing ITS time in an ITS-Station
Time-to-Alert: maximum allowable elapsed time from the onset of a Parameter Failure until the equipment annunciates
the alert
velocity: vector indicating speed in a particular direction
vertical velocity vector: projection of the 3D velocity vector on the normal vector of the WGS84 [6] Ellipsoid
3.2 Symbols
For the purposes of the present document, the following symbols apply:
Tsys ITS Station Time
3.3 Abbreviations
For the purposes of the present document, the following abbreviations apply:
3D 3 Dimensional
ACC Automatic Crouse Control
ACK Acknowledgement
ASN Abstract Syntax Notation
BSA Basic Set of Applications
CA Cooperative Awareness (service)
ETSI

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10 Draft ETSI EN 302 890-2 V2.1.1 (2020-03)
CACC Cooperative Adaptive Cruise Control
CAM Cooperative Awareness Message
CCAM Cooperative, Connected and Automated Mobility
CDD Common Data Dictionairy
CP Collective Perception (service)
CVIS Cooperative Vehicle-Infrastructure Systems
DEN Decentralized Environmental Notification
DENM Decentralized Environmental Notification Message
D-GNSS Differential Global Navigation Satellite System
EDAS EGNOS data access service
EGNOS European Geostationary Navigation Overlay Service
FA-SAP Interfaces to ITS applications
FTM Fine Tuning Measurement
GLONASS GLObal NAvigation Satellite System
GNSS Global Navigation Satellite Systems
GPC GNSS Positioning Correction
GPS Global Positioning System
GRM GPS raw data message
IETF Internet Engineering Task Force
ISO International Organization for Standardization
ITRF International Terrestrial Reference Frame
ITS Intelligent Transport System
ITS-C ITS Constellation
ITS-S ITS Station
MAC Media Access Control
NA Not Applicable
NF-SAP Interfaces to ITS applications
NGA National Geospatial-intelligence Agency
NRTK Network Real Time Kinematic
NTP Network Time Protocol
PoTi Position and Time
PPP Precise Point Positioning
PSID Provider Service Identifier
RAN Radio Access Network
RF Radio Frequency
RFC Request For Comment
R-ITS-S Roadside ITS-Station
RTCM Radio Technical Commission for Maritime services
RTCMEM Radio Technical Commission for Maritime Services Environmental Message
RTK Real Time Kinematic
SA Service Announcement
SAM Service Announcement Message
SF-SAP Interfaces to the Security entity
SI Standard International
SIFS Short InterFrame Space
SLR Satellite Laser Ranging
SPATEM Signal Phase and Timing Environmental Message
SSR Sirius Satellite Radio
TAI International Atomic Time scale
UE User Equipment
UTC Coordinated Universal Time
UWB Ultra Wide Band
VLBI Very-Long-Baseline Interferometry
VRU Vulnerable Road User
WGS World Geodetic System
WGS84 World Geodetic System 1984
ETSI

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11 Draft ETSI EN 302 890-2 V2.1.1 (2020-03)
4 Position and Time entity introduction
4.1 Introduction
ITS applications such as specified in the Basic System Application specification (BSA) ETSI TR 102 638 [i.2] require
the exchange of position and time information as part of the information exchange among ITS-Ss. As initial ITS
location based services, the Cooperative Awareness (CA) basic service ETSI EN 302 637-2 [i.3] and similar, the road
traffic event Decentralized Event Notification (DEN) basic service ETSI EN 302 637-3 [i.4] are developed. These
services and their data exchanges are dependent on position and time information. In this and the following clauses it is
understood that "position" means kinematic and attitude state as defined in clause 5.4.1 which includes attitude and
movement parameters including velocity, heading, horizontal speed and optionally others.
In order to realize road ITS safety related applications, ITS-Ss need to have an absolute knowledge about their position
and have a common synchronized knowledge about time to be able to value information received from another ITS-Ss.
To realize this absolute knowledge about position and time, an ITS-S may be equipped with a Global Navigation
Satellite System (GNSS) making use of Galileo or GPS and/or other satellite navigation technologies, providing
satellite positioning information to the PoTi entity.
Depending on the applications supported by an ITS-S, the qualitive requirements on the accuracy, integrity and
reliability of the position and time references may vary. As the CA basic service (ETSI EN 302 637- [i.3]) specifies,
road safety applications may req
...

SLOVENSKI STANDARD
oSIST prEN 302 890-2 V2.1.1:2020
01-junij-2020
Inteligentni transportni sistemi (ITS) - Funkcija zmogljivostne plasti - 2. del:
Upravljanje položaja in časa (PoTi) - Izdaja 2
Intelligent Transport Systems (ITS) - Facilities Layer function - Part 2: Position and Time
management (PoTi) - Release 2
Ta slovenski standard je istoveten z: ETSI EN 302 890-2 V2.1.1 (2020-03)
ICS:
35.240.60 Uporabniške rešitve IT v IT applications in transport
prometu
oSIST prEN 302 890-2 V2.1.1:2020 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 302 890-2 V2.1.1:2020

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oSIST prEN 302 890-2 V2.1.1:2020
Draft ETSI EN 302 890-2 V2.1.1 (2020-03)






EUROPEAN STANDARD
Intelligent Transport Systems (ITS);
Facilities Layer function;
Part 2: Position and Time management (PoTi);
Release 2

---------------------- Page: 3 ----------------------
oSIST prEN 302 890-2 V2.1.1:2020
 2 Draft ETSI EN 302 890-2 V2.1.1 (2020-03)



Reference
DEN/ITS-00182
Keywords
facility, ITS, time-stamping

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
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
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Contents
Intellectual Property Rights . 5
Foreword . 5
Modal verbs terminology . 5
Introduction . 6
1 Scope . 7
2 References . 7
2.1 Normative references . 7
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 Position and Time entity introduction . 11
4.1 Introduction . 11
4.2 Service provided by the PoTi entity . 11
5 PoTi functional description . 12
5.1 PoTi in the ITS Domain . 12
5.2 ITS Constellation . 12
5.3 PoTi in the ITS Station (ITS-S) architecture . 13
5.4 PoTi entity functional architecture . 14
5.4.1 General . 14
5.4.2 Position information Management . 14
5.4.3 Position Augmentation . 15
5.4.4 Reference coordinate System Conversion . 15
5.4.5 Time information Management . 15
5.4.6 Time synchronization . 15
5.4.7 Time reference system conversion Service . 15
5.5 PoTi Interfaces . 16
5.5.1 Interface to ITS applications (FA-SAP). 16
5.5.2 Interfaces to the Networking and Transport Layer (NF-SAP) . 17
5.5.3 Interfaces to the Management entity (MF-SAP) . 17
5.5.4 Interfaces to the Security entity (SF-SAP) . 17
5.5.5 Interfaces to other Facility layer entities . 18
6 Position and time requirements . 18
6.1 Requirements related to PoTi functions . 18
6.2 ITS-S reference position . 20
6.2.1 Introduction. 20
6.2.2 ITS-S reference position for passenger cars . 20
6.2.3 ITS-S reference position for Trucks . 22
6.2.4 ITS-S reference position for Busses . 28
6.2.5 ITS-S reference position for Motorcycles, mopeds and bicycles . 29
6.2.6 ITS-S reference position for Pedestrians . 31
6.2.7 ITS-S reference position for Special Vehicles . 31
6.2.8 ITS-S reference position for City-Tram . 31
6.2.9 ITS-S reference position for Roadside ITS Stations (R-ITS-S's) . 32
6.3 Position and time confidence. 32
6.3.1 General requirements related to confidence . 32
6.3.2 Confidences related to Position Information Management . 33
6.3.2.1 Horizontal Position confidence . 33
6.3.2.2 Vertical Position confidence . 33
6.3.2.3 Horizontal Speed confidence . 33
6.3.2.4 Heading confidence . 33
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6.3.2.5 Confidence of other quantities . 34
6.3.2.6 Other accuracy estimations . 34
6.3.3 Confidences related to Reference Coordinate System Conversion Management . 34
6.3.3.1 Relative Position confidence . 34
6.3.4 Confidences related to Time Information Management . 34
7 Augmentation services . 34
7.1 Introductions . 34
7.2 GNSS Positioning Correction (GPC) Augmentation Service . 35
7.2.1 Introduction. 35
7.2.2 GPC requirements . 35
7.2.3 GPC Data exchange between R-ITS-S's . 36
7.3 R-ITS-S ranging augmentation Service . 37
7.3.1 Introduction. 37
7.3.2 Ranging service announcements . 38
7.3.2.1 Introduction . 38
7.3.2.2 Ranging Service Application Data . 38
7.3.3 Measurement. 39
7.3.4 Ranging Rate . 40
7.3.5 Security . 40
Annex A (normative): ASN.1 specification of messages . 41
A.1 ASN.1 specification of ranging service application data . 41
History . 42


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Intellectual Property Rights
Essential patents
IPRs essential or potentially essential to normative deliverables 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 (https://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.
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.
Foreword
This draft European Standard (EN) has been produced by ETSI Technical Committee Intelligent Transport Systems
(ITS), and is now submitted for the combined Public Enquiry and Vote phase of the ETSI standards EN Approval
Procedure.
The present document is part 2 of a multi-part deliverable covering Facilities Layer function, as identified below:
Part 1: "Services Announcement (SA) specification";
Part 2: "Position and Time management (PoTi)".
The present document is based on inputs provided by various European projects including AutoNet, Concorda,
Ensemble, Hights, PRoPART, Dutch-Germany-Austria Corridor, Scope@F, A58 (NL), PRE-DRIVE C2X, DRIVE
C2X, SafeSpot, CVIS, CoVeL, SCOR@F, simTD, etc.

Proposed national transposition dates
Date of latest announcement of this EN (doa): 3 months after ETSI publication
Date of latest publication of new National Standard
or endorsement of this EN (dop/e): 6 months after doa
Date of withdrawal of any conflicting National Standard (dow): 6 months after doa

Modal verbs terminology
In the present document "shall", "shall not", "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.
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Introduction
Intelligent Transportation Systems Cooperative, Connected and Automated Mobility(CCAM) related use cases in the
ITS environment as specified in the ETSI ITS architecture (ETSI EN 302 665 [i.1]) can be distributed over multiple ITS
stations (ITS-S's). ITS-S's interact in the ITS system to exchange sensor data and traffic related information to make
each other aware of traffic safety or traffic efficiency circumstances and situations by which each ITS-S equipped road
user, whether automated or not, can improve their safety and efficiency related decisions.

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1 Scope
The present document provides the specification of the Position and Time (PoTi) services. It includes functional and
operational requirements for the position and time data to support ITS Applications. In addition, it includes the
definition of syntax and semantics of messages exchanged between ITS-Stations (ITS-Ss) to augment the position and
time accuracy. Finally, it specifies the facilities layer protocol in support of such message exchanges.
2 References
2.1 Normative 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.
Referenced documents which are not found to be publicly available in the expected location might be found at
https://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.
The following referenced documents are necessary for the application of the present document.
[1] ETSI TS 103 301: "Intelligent Transport Systems (ITS); Vehicular Communications; Basic Set of
Applications; Facilities layer protocols and communication requirements for infrastructure
services".
[2] RTCM 10402.3: "Recommended Standards for Differential GNSS (Global Navigation Satellite
Systems) Service".
[3] RTCM 10403.3: "Differential GNSS (Global Navigation Satellite Systems) Services - Version 3".
[4] ETSI EN 302 663 (V1.3.1) (2020-01): "Intelligent Transport Systems (ITS); ITS-G5 Access layer
specification for Intelligent Transport Systems operating in the 5 GHz frequency band".
[5] ETSI EN 302 890-1 (V1.2.1) (2019-07): "Intelligent Transport Systems (ITS); Facilities layer
function; Part 1: Services Announcement (SA) specification".
[6] World Geodetic System 84 (WGS84).
NOTE: Available at http://earth-info.nga.mil/GandG/update/index.php?dir=wgs84&action=wgs84#tab_wgs84-
res.
[7] ISO 8855 (2011): "Road Vehicles -- Vehicle dynamics and road-holding ability -- Vocabulary".
[8] ETSI TS 103 248: "Intelligent Transport Systems (ITS); GeoNetworking; Port Numbers for the
Basic Transport Protocol (BTP)".
[9] ISO 5725-1 (1994), "Accuracy (trueness and precision) of measurement methods and results --
Part 1: General principles and definitions".
[10] ETSI TS 102 894-2: "Intelligent Transport Systems (ITS); Users and applications requirements;
Part 2: Applications and facilities layer common data dictionary".
[11] ETSI EN 302 931 (V1.1.1): "Intelligent Transport Systems (ITS); Vehicular Communications;
Geographical Area Definition".
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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 with regard to a particular subject area.
[i.1] ETSI EN 302 665: "Intelligent Transport Systems (ITS); Communications Architecture".
[i.2] ETSI TR 102 638 (V1.1.1): "Intelligent Transport Systems (ITS); Vehicular Communications;
Basic Set of Applications; Definitions".
[i.3] ETSI EN 302 637-2: "Intelligent Transport Systems (ITS); Vehicular Communications; Basic Set
of Applications; Part 2: Specification of Cooperative Awareness Basic Service".
[i.4] ETSI EN 302 637-3: "Intelligent Transport Systems (ITS); Vehicular Communications; Basic Set
of Applications; Part 3: Specifications of Decentralized Environmental Notification Basic
Service".
[i.5] ETSI TS 102 894-1 (V1.1.1): "Intelligent Transport Systems (ITS); Users and applications
requirements; Part 1: Facility layer structure, functional requirements and specifications".
[i.6] ETSI TR 103 299: "Intelligent Transport System (ITS); Cooperative Adaptive Cruise Control
(CACC); Pre-standardization study".
[i.7] ETSI TS 103 324: "Intelligent Transport Systems (ITS); Cooperative Perception Services".
[i.8] ETSI TS 103 246-1 (V1.2.1) (2017-03): "Satellite Earth Stations and Systems (SES); GNSS based
location systems; Part 1: Functional requirements".
[i.9] EUREF, European Terrestrial Reference System (ETRS89).
NOTE: Available at http://etrs89.ensg.ign.fr.
[i.10] ETSI TR 101 607 (V1.1.1) (2013-05): "Intelligent Transport Systems (ITS); Cooperative ITS
(C-ITS); Release 1".
[i.11] ISO 3534-1 (2009-10): "Statistics - Vocabulary and symbols - Part 1: General statistical terms and
terms".
[i.12] ETSI TS 136 305 (V11.2.0): "LTE; Evolved Universal Terrestrial Radio Access Network (E-
UTRAN); Stage 2 functional specification of User Equipment (UE) positioning in E-UTRAN
(3GPP TS 36.305 version 11.2.0 Release 11)".
[i.13] IETF RFC 5905 (June 2010): "Network Time Protocol Version 4: Protocol and Algorithms
Specification".
[i.14] IEC 60050: "International Electrotechnical Vocabulary", 113-01-08 (instant), 113-01-10 (time
interval), 113-01-13 (duration).
[i.15] Quasi-Zenith Satellite System Interface Specification Centimeter Level Augmentation Service (IS
-QZSSQZSS -L6 -00 1).
NOTE: Available at https://qzss.go.jp/en/technical/download/pdf/ps-is-qzss/is-qzss-l6-001.pdf.
[i.16] IETF RFC 8173 (June 2017): "Precision Time Protocol Version 2 (PTPv2) Management
Information Base".
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3 Definition of terms, symbols and abbreviations
3.1 Terms
For the purposes of the present document, the following terms apply:
accuracy: closeness of a measured value to a standard or known value
heading: orientation of the horizontal velocity vector with respect to the WGS84 [6] North (clockwise), unless
otherwise noted
horizontal speed: magnitude of horizontal velocity-vector of the reference position point
horizontal velocity vector: projection of the 3D velocity vector on the WGS84 [6] ellipsoid
integrity risk: probability, per unit of time, of having a Parameter Failure without issuing an alert within the
Time-to-Alert
ITS constellation: group of ITS-S's which are exchanging ITS data among themselves
ITS time: time based on TAI
st
NOTE: Epoch of this time is set to 2004-01-01T00:00:00Z, that is 0 seconds on 1 of January 2004 UTC.
parameter failure: failure occurring when the position and time entity is unable to estimate parameters with an error
less than the maximum tolerable error (err > err_max)
position integrity: measure of the trust that can be placed in the correctness of the estimated Parameters supplied by the
Position and Time entity
NOTE: Integrity includes the ability of the equipment (at the Position and Time entity and/or User level) to
compute timely and valid alerts when the estimated Parameters do not need to be used for the operation of
interest.
protection level: estimated bound on the Parameter Error from the Position and Time entity at a defined confidence
level such as 50 %, 75 %, 95 %, 99 %, etc., delivered with the Parameters
station clock: clock representing ITS time in an ITS-Station
Time-to-Alert: maximum allowable elapsed time from the onset of a Parameter Failure until the equipment annunciates
the alert
velocity: vector indicating speed in a particular direction
vertical velocity vector: projection of the 3D velocity vector on the normal vector of the WGS84 [6] Ellipsoid
3.2 Symbols
For the purposes of the present document, the following symbols apply:
Tsys ITS Station Time
3.3 Abbreviations
For the purposes of the present document, the following abbreviations apply:
3D 3 Dimensional
ACC Automatic Crouse Control
ACK Acknowledgement
ASN Abstract Syntax Notation
BSA Basic Set of Applications
CA Cooperative Awareness (service)
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CACC Cooperative Adaptive Cruise Control
CAM Cooperative Awareness Message
CCAM Cooperative, Connected and Automated Mobility
CDD Common Data Dictionairy
CP Collective Perception (service)
CVIS Cooperative Vehicle-Infrastructure Systems
DEN Decentralized Environmental Notification
DENM Decentralized Environmental Notification Message
D-GNSS Differential Global Navigation Satellite System
EDAS EGNOS data access service
EGNOS European Geostationary Navigation Overlay Service
FA-SAP Interfaces to ITS applications
FTM Fine Tuning Measurement
GLONASS GLObal NAvigation Satellite System
GNSS Global Navigation Satellite Systems
GPC GNSS Positioning Correction
GPS Global Positioning System
GRM GPS raw data message
IETF Internet Engineering Task Force
ISO International Organization for Standardization
ITRF International Terrestrial Reference Frame
ITS Intelligent Transport System
ITS-C ITS Constellation
ITS-S ITS Station
MAC Media Access Control
NA Not Applicable
NF-SAP Interfaces to ITS applications
NGA National Geospatial-intelligence Agency
NRTK Network Real Time Kinematic
NTP Network Time Protocol
PoTi Position and Time
PPP Precise Point Positioning
PSID Provider Service Identifier
RAN Radio Access Network
RF Radio Frequency
RFC Request For Comment
R-ITS-S Roadside ITS-Station
RTCM Radio Technical Commission for Maritime services
RTCMEM Radio Technical Commission for Maritime Services Environmental Message
RTK Real Time Kinematic
SA Service Announcement
SAM Service Announcement Message
SF-SAP Interfaces to the Security entity
SI Standard International
SIFS Short InterFrame Space
SLR Satellite Laser Ranging
SPATEM Signal Phase and Timing Environmental Message
SSR Sirius Satellite Radio
TAI International Atomic Time scale
UE User Equipment
UTC Coordinated Universal Time
UWB Ultra Wide Band
VLBI Very-Long-Baseline Interferometry
VRU Vulnerable Road User
WGS World Geodetic System
WGS84 World Geodetic System 1984
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4 Position and Time entity introduction
4.1 Introduction
ITS applications such as specified in the Basic System Application specification (BSA) ETSI TR 102 638 [i.2] require
the exchange of position and time information as part of the information exchange among ITS-Ss. As initial ITS
location based services, the Cooperative Awareness (CA) basic service ETSI EN 302 637-2 [i.3] and similar, the road
traffic event Decentralized Event Notification (DEN) basic service ETSI EN
...