ISO 17572-4:2020

INTERNATIONAL ISO
STANDARD 17572-4
First edition
2020-04
Intelligent transport systems (ITS) —
Location referencing for geographic
databases —
Part 4:
Precise relative location references
(precise relative profile)
Reference number
©
ISO 2020
© ISO 2020
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address
below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Fax: +41 22 749 09 47
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2020 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Abbreviated terms . 2
5 Conformance . 2
6 Requirements for a location referencing standard . 2
7 Conceptual data model for LFMs . 3
7.1 Role of conceptual model . 3
7.2 Components of conceptual model . 3
7.3 Description of the conceptual model . 3
7.4 Location categories . 3
7.5 Conceptual model of a road network. 4
7.6 Conceptual model of area locations . 5
8 Specification of LRs for precise relative information . 5
8.1 General concept . 5
8.1.1 Methods to be defined in this document . 5
8.1.2 Concept of Method 1: Lane number counting . 5
8.1.3 Concept of Method 2: Displacement from a reference point . 6
8.2 Specification for contents delivering message . 7
8.2.1 Structure of the message . 7
8.2.2 Definition of the components . 8
8.3 Use cases and examples of contents for location referencing messages .11
Annex A (normative) Abstract test suite .12
Annex B (informative) Basic lane model of a road .13
Annex C (informative) Use cases for Precise Relative Location Referencing Method .14
Annex D (informative) Use cases for elements of Precise Relative Location Referencing Method.17
Annex E (informative) Implementation examples of Precise Relative Location Referencing
Method .25
Bibliography .28
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see www .iso .org/
iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 204, Intelligent transport systems.
A list of all parts in the ISO 17572 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
iv © ISO 2020 – All rights reserved

Introduction
A Location Reference (LR) is a unique identification of a geographic object. In a digital world, a real-
world geographic object can be represented by a feature in a geographic database. An example of a
commonly known LR is a postal address of a house. Examples of object instances include a particular
exit ramp on a particular motorway, a road junction or a hotel. For efficiency reasons, LRs are often
coded. This is especially significant if the LR is used to define the location for information about
various objects between different systems. For ITS, many different types of real-world objects will be
addressed. Amongst these, the LR of the road network, or components thereof, is a particular focus.
Communication of a LR for specific geographic phenomena, corresponding to objects in geographic
databases, in a standard, unambiguous manner is a vital part of an integrated ITS system in which
different applications and sources of geographic data will be used. Location Referencing Methods
(LRM), methods of referencing object instances, differ by applications, by the data model used to create
the database, or by the enforced object referencing imposed by the specific mapping system used to
create and store the database. A standard LRM allows for a common and unambiguous identification
of object instances representing the same geographic phenomena in different geographic databases
produced by different vendors, for varied applications, and operating on multiple hardware/software
platforms. If ITS applications using digital map databases are to become widespread, data reference
across various applications and systems must be possible. Information prepared on one system, such as
traffic messages, need to have LRs that are interpretable by all receiving systems. A standard method
to refer to specific object instances is essential to achieving such objectives.
Japanese, Korean, Australian, Canadian, North American and European ITS bodies all support LR
activities . In Japan, precise location referencing is needed due to the increasing introduction of
C-ITS and automated driving systems such as SIP-adus. Due to the mechanisms for the creation of
digital maps, even with high accuracies, representation of a real-world position will differ between
maps. Additionally, because of crustal movement over time, discrepancies would occur for locations
determined simply by measurements from ground-based objects if only latitude and longitude were
utilized.
Location referencing at the precise relative level is needed to describe exact positions and exchange
LRs accordingly. Location referencing at the precise relative level requires referencing to a position
that is sufficiently detailed and accurate to distinguish the lane in which the object exists, and to
distinguish the position within a lane or a lane junction. This does not imply the need to provide an
absolute position with a high accuracy.
This document provides specifications for location referencing for ITS systems (although other
committees or standardization bodies may subsequently consider extending it to a more generic
context).
INTERNATIONAL STANDARD ISO 17572-4:2020(E)
Intelligent transport systems (ITS) — Location referencing
for geographic databases —
Part 4:
Precise relative location references (precise relative
profile)
1 Scope
This document describes and lists the characteristics of the Precise Relative Location Referencing
Method (PRLRM) which describes precise relative locations in the context of geographic databases and
is used to locate transport-related objects in an encoder system as well as in the decoder side.
This document does not define a physical format for implementing the PRLRM. However, the
requirements for physical formats are defined. This document does not define details of the Precise
Relative Location Referencing System (PRLRS), i.e. how the PRLRM is to be implemented in software,
hardware or processes.
This document specifies PRLRM, comprising:
— conceptual data model for Location Referencing Methods (LFMs);
— specification of location referencing for precise relative information;
— use cases for Precise Relative Location References (informative Annex C);
— use cases for elements of Precise Relative Location References (informative Annex D);
— implementation of Precise Relative Location References (Japanese example) (informative Annex E).
This document defines methods that enable exchange location information of the object to be referenced
in the lane or the lane junction. This document does not specify the road (link) on which the object of
reference exists.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 17572-1:2015, Intelligent transport systems (ITS) — Location referencing for geographic databases —
Part 1: General requirements and conceptual model
ISO 17572-2:2018, Intelligent transport systems (ITS) — Location referencing for geographic databases —
Part 2: Pre-coded location references (pre-coded profile)
ISO 17572-3:2015, Intelligent transport systems (ITS) — Location referencing for geographic databases —
Part 3: Dynamic location references (dynamic profile)
ISO 19148:2012, Geographic information — Linear referencing
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 175
...