ISO/TS 14819-3:2000
(Main)Traffic and Travel Information (TTI) — TTI messages via traffic message coding — Part 3: Location referencing for ALERT-C
Traffic and Travel Information (TTI) — TTI messages via traffic message coding — Part 3: Location referencing for ALERT-C
Information trafic et voyageurs (TTI) — Messages TTI via le codage de messages du trafic — Partie 3: Référence d'emplacement pour ALERT-C
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Standards Content (Sample)
TECHNICAL ISO/TS
SPECIFICATION 14819-3
First edition
2000-11-15
Traffic and Traveller Information (TTI) —
TTI messages via traffic message coding —
Part 3:
Location referencing for ALERT-C
Information trafic et voyageurs (TTI) — Messages TTI via le codage de
messages du trafic —
Partie 3: Référence d'emplacement pour ALERT-C
Reference number
ISO/TS 14819-3:2000(E)
©
ISO 2000
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ISO/TS 14819-3:2000(E)
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ISO/TS 14819-3:2000(E)
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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3.
The main task of technical committees is to prepare International Standards. Draft International Standards adopted
by the technical committees are circulated to the member bodies for voting. Publication as an International
Standard requires approval by at least 75 % of the member bodies casting a vote.
In other circumstances, particularly when there is an urgent market requirement for such documents, a technical
committee may decide to publish other types of normative document:
� an ISO Publicly Available Specification (ISO/PAS) represents an agreement between technical experts in an
ISO working group and is accepted for publication if it is approved by more than 50 % of the members of the
parent committee casting a vote;
� an ISO Technical Specification (ISO/TS) represents an agreement between the members of a technical
committee and is accepted for publication if it is approved by 2/3 of the members of the committee casting a
vote.
An ISO/PAS or ISO/TS is reviewed every three years with a view to deciding whether it can be transformed into an
International Standard.
Attention is drawn to the possibility that some of the elements of this Technical Specification may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO/TS 14819-3 was prepared by the European Committee for Standardization (CEN) in collaboration with
Technical Committee ISO/TC 204, Transport information and control systems, in accordance with the Agreement
on technical cooperation between ISO and CEN (Vienna Agreement).
Throughout the text of this document, read ".this European Prestandard." to mean ".this Technical
Specification.".
ISO 14819 consists of the following parts, under the general title Traffic and Traveller Information (TTI) — TTI
messages via traffic message coding:
— Part 1: Coding protocol for Radio Data System — Traffic Message Channel (RDS-TMC) using ALERT-C
— Part 2: Event and information codes for Radio Data System — Traffic Message Channel (RDS-TMC)
— Part 3: Location referencing for ALERT-C
Annexes A, B and ZA form a normative part of this part of ISO 14819. Annex C is for information only.
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ISO/TS 14819-3:2000(E)
CONTENTS
Page
CONTENTS iv
FOREWORD v
INTRODUCTION vi
1SCOPE 1
2 NORMATIVE REFERENCES 2
3 ABBREVIATIONS 3
4 LOCATION CODING 4
4.1 LOCATION TABLES 4
4.2 TMC LOCATION CATEGORIES, TYPES AND SUBTYPES 8
4.3 LOCATION TABLE CONTENT 8
4.4 DETAILED JUNCTION REFERENCING 12
4.5 DETAILED SITUATION LOCATIONS 12
4.6 ONE AND TWO WAY LOCATIONS 12
ANNEX A (NORMATIVE) TMC LOCATION CATEGORIES, TYPES AND SUBTYPES 15
A.1 AREA LOCATIONS 15
ANNEX B (NORMATIVE) LOCATION TABLE NUMBERS AND SERVICES 24
ANNEX C (INFORMATIVE) BACKGROUND INFORMATION 25
C.1 OVERALL APPROACH 25
C.2 METHODS 27
ANNEX ZA (NORMATIVE) NORMATIVE REFERENCES TO INTERNATIONAL
PUBLICATIONS WITH THEIR RELEVANT EUROPEAN PUBLICATIONS 33
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ISO/TS 14819-3:2000(E)
FOREWORD
The text of ENV ISO 14819-3:2000 has been prepared by Technical Committee CEN/TC
278 "Road transport and traffic telematics", the secretariat of which is held by NEN, in
collaboration with Technical Committee ISO/TC 204 "Transport information and control
systems".
This pre-Standard was prepared by Working Group 7 of CEN TC278. In the field of Traffic
and travel Information, the innovative rate is high, with many research and development
projects under way in many countries, and there is a need to establish prospective standards
which allow manufacturers to introduce competitive products to the market in the knowledge
that they can accommodate the future issues of the standard(s) without fundamental change
to equipment.
No known national standards (identical or conflicting) exist on this subject.
According to the CEN/CENELEC Internal Regulations, the national standards organizations
of the following countries are bound to announce this European Prestandard: Austria,
Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland,
Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the
United Kingdom.
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ISO/TS 14819-3:2000(E)
INTRODUCTION
This document sets out ways of specifying places and positions in traffic and travel information
messages, including RDS-TMC messages (the Radio Data System - Traffic Message
Channel).
It defines the structure and semantics of location tables for Traffic Information Centres (TICs)
and receivers.
1. TRAFFIC AND TRAVEL MESSAGES
a) Traffic and travel information is created and updated in an originating
database, by human operators or automated systems. Information is
transferred to one or more remote systems by means of messages.
b) In this context, a message is a collection of data which is exchanged to
convey information for an agreed purpose between two or more parties.
Traffic and travel messages are digitally coded sets of data exchanged by
interested parties, which convey information about traffic, travel and/or
transport networks. Digital coding can be alphanumeric, as in EDIFACT, or
binary, as in RDS-TMC.
c) The traffic and travel messages developed in ATT programmes of the
European Commission are open, non-proprietary proposals for standards
intended to serve the public interest by facilitating interconnection and
interoperability of the relevant information systems.
2. LOCATION REFERENCING
a) Location references provide the means of saying where in traffic and travel
messages.
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ISO/TS 14819-3:2000(E)
1SCOPE
This European Prestandard primarily addresses the needs of RDS-TMC ALERT-C
messages, which are ready for near-term implementation. However, the modular approach
used here is intended to facilitate future extension of the location referencing rules to other
traffic and travel messaging systems.
The location referencing rules defined in this European Prestandard address the specific
requirements of Traffic Message Channel (TMC) systems, which use abbreviated coding
formats to provide TTI messages over mobile bearers (e.g. GSM, DAB) or via exchange
protocols like DATEX. In particular, the rules address the Radio Data System - Traffic
Message Channel (RDS-TMC), a means of providing digitally-coded traffic and travel
information to travellers using a silent data channel (RDS) on FM radio stations, based on
the ALERT-C protocol.
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ISO/TS 14819-3:2000(E)
2 NORMATIVE REFERENCES
This European Prestandard incorporates by dated or undated reference, provisions from
other publications. These normative references are cited at the appropriate places in the text
and the publications are listed hereafter. For dated references, subsequent amendments to
or revisions of any of these publications apply to this European Prestandard only when
incorporated in it by amendment or revision. For undated references the latest edition of the
publication referred to applies (including amendments).
EN 50067 Specification of the Radio Data System (RDS) for VHF/FM
sound broadcasting in the frequency range from 87,5 to 108,0
MHz.
prEN ISO 14819-1:1999 Traffic and travel Information (TTI) - TTI Messages via traffic
message coding - Part 1: Coding protocol for Radio Data
System - Traffic Message Channel (RDS-TMC) using ALERT-C
(ISO/DIS 14819-1:1999)
ENV ISO 14825 Geographic Data Files
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ISO/TS 14819-3:2000(E)
3 ABBREVIATIONS
For the purpose of this European Prestandard, the following abbreviations apply:
ALERT Advice and problem Location for European Road Traffic (name of a European
project in the first half of the 1990’s to develop TTI messaging)
(A)TT (Advanced) Transport Telematics
CENELEC Comité Européen de Normalisation ELECtrotechnique
DAB Digital Audio Broadcasting (future wide-band digital successor of FM)
DATEX DATa Exchange network (agreement between traffic information centres for
exchange of traffic and travel information, and protocol for such exchange)
EDIFACT Electronic Data Interchange For Administration Commerce and Transport
GDF Geographic Data Files (European Prestandard ENV ISO 14825 for modelling
and exchange of geographic data for transport telematics applications. Currently
under review by CEN and ISO.)
RDS Radio Data System (digital information channel on FM sub carrier)
TIC Traffic Information Centre
TMC Traffic Message Channel
TTI Traffic and Travel Information
WGS 84 World Geodetic System 1984
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ISO/TS 14819-3:2000(E)
4 LOCATION CODING
Location references used by RDS-TMC are covered by the location referencing rules defined
in this section. The ALERT-C coding protocol for RDS-TMC is defined in prEN ISO 14819-
1:1999.
ALERT-C supports a digital, silent data broadcast service for motorists, providing information
about many kinds of traffic situations. This includes roadwork, weather and traffic incident
information relating to major national and international roads, regional roads and local or
urban roads.
4.1 LOCATION TABLES
Within RDS-TMC, locations are identified and referenced by their location code. A given
RDS-TMC service uses a pre-defined location table, containing the pre-stored details of the
locations that can be referenced in messages from that service.
A location code in such a message refers and serves as a tabular ‘address’ of the pre-stored
location details in the location table used by the service. A real world location may have
more than one location code within the same location table. However, within a given location
table, each location code refers to one and only one location. A location code has a number
in the range 1 to 63,487.
Note In ALERT-C, a further 2048 numbers are reserved for EUROAD (see prEN ISO
14819-1:1999) and other forms of referencing.
A table may contain a maximum number of 65,536 codes allocated in the following way:
Location code Use
0reserved
1 - 63,487 free for normal location coding
63,488 - 64,511 for special purposes
64,512 - 65,532 for EUROAD
64,533 - 65,535 special functions
Note EUROAD is a coding mechanism within ALERT-C to reference in a specific type of
ALERT-C message (the EUROAD message) a location belonging to a different location
table.
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ISO/TS 14819-3:2000(E)
4.1.1 Hierarchical structure
RDS-TMC location tables use a hierarchical structure of pre-defined locations. A system of
pointers provides upward references to higher-level locations of which the specified location
forms a part.
Example Kent would have an upward area reference to south-east England. South-east
England may be referenced up to the UK, then the British Isles, then Europe, etc. (Figure
4.1).
Figure 4.1 - Upward Area Referencing
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ISO/TS 14819-3:2000(E)
Junction 25 on the M1 motorway in UK would have a linear referencetoamotorway
segment, e.g. Leicester - Sheffield. This segment could then be referenced up to the whole
road (the M1 Motorway).
Hierarchical tables help to make location referencing simple and unambiguous. A major
benefit of hierarchical tables is that they facilitate automated sorting and selection of
information for users. However, both hierarchical and unstructured tables are currently used
in ATT applications.
4.1.2 Offsets
Certain linear locations, and point locations, may point to previous and next locations of the
same type. This is indicated by negative and positive offsets.
Example: Junction 25 on a motorway may be offset to Junction 26 in the positive direction,
and to Junction 24 in the negative direction. A sign convention adopted at the time of coding
locations specifies the positive direction of travel along each road (Figure 4.2).
positive direction
J24 J25 J26
negative offset positive offset
Figure 4.2. - Offsets
4.1.3 Location types
Location types and subtypes are required for language independence of the information
given, and to tell the receiving system what data fields to expect.
At the highest level, locations fall into three categories:
1. area locations
2. linear locations
3. point locations
Within each category, location types are distinguished (in principle) whenever a location is
functionally distinct in the way it must be handled by the message recipient. Therefore a set
of predefined location types and subtypes is set out in Annex A.
Subtypes can be used to give further details of (for example) facilities available at a
particular location, such as a service area. The current list, in Annex A, will be added to as
further needs are agreed.
Official translations of the language-independent terms that describe location types and
subtypes should be agreed on a national level.
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4.1.4 Direction of the road
The predefined direction of the road (see section 4.1.2) is reflected in the positive and
negative offsets in the location table and in the order of the names of the end points of a
road or road segment (see table in 4.3.3).
When newly specifying positive directions along roads within pre-defined tables, it is
recommended to use geographic positive directions relative to the co-ordinate system, i.e.
on the Northern Hemisphere from south to north and from west to east.
For ring roads the clockwise travel direction is recommended positive.
In any case it is not allowed to reverse the direction along continuous and / or connecting
segments of a road, e.g. at administrative borders.
4.1.5 Country codes and location table numbers
With ALERT-C, it is assumed that RDS-TMC service and location tables are organised and
defined on a country by country basis. Therefore each service and each location table is
associated to a country code in the range 1-15 (hexadecimal 1-F) as described in EN50067.
A service and the location table it uses must have the same country code. There can be
more than 1 location table per country. They are distinguished by an additional location table
number in the range 1-63.
Each country code is shared by more than one country within Europe and the surrounding
territories. To avoid ambiguity in European RDS-TMC location referencing, ranges of
location table numbers are allocated to specific countries, in accordance with the table given
in Annex B.
In this way, each location table is uniquely identified by its country code and location table
number. As can be concluded from Annex B, a country like e.g. Austria can have at most 8
location tables.
4.1.6 Unique location code
The combination of country code (4 bits), location table number (6 bits) and location code
(16 bits) defines an extended location code, which is unique throughout Europe.
4.1.7 Constraints
Constraints on location coding may in future be agreed, modelled and documented. At
present, however, national authorities are free to allocate definitive location codes as they
wish to locations specified in accordance with these rules.
4.1.8 Future developments
Within each location table, space (unallocated location codes) must be left to accommodate
future requirements for additional locations (to deal with new construction, and location
referencing requirements not originally foreseen).
Once a location has been allocated, it cannot easily be re-allocated (in an RDS-
TMC/ALERT-C environment). Therefore, all existing locations and their associated location
codes should be regarded as fixed. However, other attributes of a location may, within
certain constraints, sometimes change (Example: name, positive offset, negative offset).
Many location table numbers are not yet allocated. The responsible agency in a country can
apply for additional location table numbers in future, to support further applications or more
detailed, regional location tables. New tables can also be issued occasionally to allow for
complete updates to existing tables. Such major changes will however be very disruptive for
users, and should be avoided as far as possible or at least not be done too frequently.
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ISO/TS 14819-3:2000(E)
4.2 TMC LOCATION CATEGORIES, TYPES AND SUBTYPES
Location categories, types and location subtypes are standardised, and specified in Annex
A. New subtypes can be proposed to CEN/TC 278 for approval, registration and publication.
Each location is described by a code, which is composed of:
� a character (A, L or P), indicating the location category (area, linear or point)
� a number indicating the type
� a dot
� a number indicating a subtype
Example P1.8 - roundabout (P = point, P1 = junction)
For types for which not a subtype is defined, the subtype code 0 (zero) has to be used to
define the type as a subtype.
Example A3.0 - country
4.3 LOCATION TABLE CONTENT
The location table content is fixed only for the purposes of definition and exchange. The
information used within specific applications or by individual manufacturers is not fixed, and
is not within the scope of these specifications.
For European consistency, one single location table content shall be adhered to for definition
and exchange purposes. In this structure, some items are mandatory; some items are
mandatory where they exist; and some items are optional.
4.3.1 Driver Information Messages (ALERT-C)
The nominal content of each record in the location table is as follows:
� location code
� code of location (sub) type
� road/junction number
� road name
� first name
� second name
� area reference
� linear reference
� negative offset
� positive offset
� urban
� intersection reference
� WGS 84 co-ordinates (longitude and latitude)
Not all of these items shall be present in every record. The table in 4.3.3 indicates which
references are required and/or allowed, according to location type.
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4.3.2 Road descriptions
4.3.2.1 Road numbers and road names
Road descriptions are normally road numbers. They shall be indicated at the highest level of
the hierarchy (e.g. road/ring road) only. In addition to the road number, a road name (e.g.
Autoroute du Nord) or other road number (e.g. E13 for A1) may be defined. If no road
number exists, a road name is mandatory (e.g. Bd Périphérique).
Some segments of a road may carry additional numbers and/or names (e.g. A6 - Autoroute du
Soleil, A4 - Kölner Ring). In the case that a road segment belongs to more than one road this
shall lead to multiple entries in the location table. If the multiple numbers and/or names do not
signify the fact that the segment is part of more than one road, they can be indicated at the
segment level in the road-name field, where required. The higher level road number still
applies.
For vehicular links, the road name can be the name of a company, e.g. Stena Sealink;
Eurotunnel; a geographic name, e.g. Simplon Tunnel, Channel Tunnel; or a marketing name,
e.g. Le Shuttle.
4.3.2.2 Junction numbers
For junctions, the field road/junction number is used to describe junction numbers, where they
exist.
4.3.3 Names
Names of locations shall normally be given in the language of the locality. However, it s also
permissible to produce versions of location tables with (bi- or multi-lingual) place names
translated into other languages.
Junction name may be a description as known by road users.
Negative and positive end-names may be precise (e.g. Dover-Calais), or approximate (e.g.
Köln - Frankfurt). Approximate names refer to nearby places which the road (usually a
motorway) does not pass directly through.
Point descriptor for intermediate points is mandatory. Where required, they can be given in
terms of kilometre/milepost references.
Table 4.1 contains an overview of the content of a location table for RDS-TMC. Mandatory
fields are shown by (M), while (m) means mandatory where it exists, and (O) means optional.
Fields not present are shown by - (dash). The first column is for explanation only. The second
column (location code) represents the key of the database, and therefore has the entry (M) for
each record in the database. The sequence of the columns in the table is not significant. Non-
empty fields in the columns area reference, linear reference, negative offset, positive offset
contain the code of the location within the same location table to which the field references.
For detailed descriptions of all location types and their codes see Annex A.
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ISO/TS
10 © ISO 2000 – All rights reserved
Table 4.1 - Content of location table for RDS-TMC
location code of location road/ road first name second name area reference linear reference negative positive ur- inter- WGS 84
4
code (sub) type junction name offset offset ban section co-
number reference ordinates
(M) continent - - name (M) - - - - - - - -
(M) country group - - name (M) - country group or-- - -- -
continent (M)
area (M) country - - name (M) - country group or-- - -- -
continent (M)
(M) other area (water - - name (M) - lowest order -- - -- -
area, fuzzy area, administrative area or
application region) other area (M)
(M) nth order area - - name (M) - nth order area (M) - - - - - -
(n = 1 to 5)
2 2
(M) road negative end positive end nth order area or-- --- -
(m) (m)
name (M) name (M) country (M)
2 2
(M) ring road name (O) - nth order area or-- - -- -
(m) (m)
country (M)
2 2
linear (M) nth order segment negative end positive end - first order segment, preceding nth subsequent-- -
(m) (m)
(n = 1, 2) name (M) name (M) road or ring road order segment nth order
(M) (m) segment (m)
(M) urban street name (O) name (O) nth order area (M) - - - - - -
-(M)
(M) vehicular link negative end positive end nth order area (O) - - - - - -
-(m)
name (M) name (M)
3 3
(M) junction junction name road number lowest order lowest order preceding subsequent (M) (m) (M)
(m) (O)
3
(m) or name of administrative area or segment, road or point (m) point (m)
intersecting other area (M) ring road (M)
3
road (O)
point (M) intermediate point - - point - lowest order lowest order preceding subsequent (M) - (M)
descriptor (M) administrative area or segment, road or point (m) point (m)
other area (M) ring road (M)
(M) other landmark - - point name - lowest order lowest order preceding subsequent (M) (O) (M)
1
point (M) administrative area or segment, road or point (m) point (m)
other area (M) ring road (M)
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Note 1 Other points include motorway service areas, and prominent landmarks such as
named, major bridges and tunnels.
Note 2 For roads, ring roads and nth order segments at least one of the two fields
road/junction number and road name shall have a value.
Note 3 For junctions at least one of the four fields road/junction number, road name, first
name and road name shall have a value.
Note 4 The column code of location (sub)type in this explanatory table contains descriptions
of location types and subtypes. In a real location table this column contains location
(sub)type codes.
4.3.4 Upward references
Two paths shall normally be provided for upward referencing in ALERT-C (see prEN ISO
14819-1:1999). The first is for area references, the second is for linear references. Additional
upward referencing paths can be used, but this is not required as part of the minimum
European standard for exchange purposes.
Upward references shall normally point to the next defined higher level. For example, a
second order area shall reference a first order area; a first order area shall reference a
country; etc.
4.3.5 Offsets
Offsets may be defined for nth order segment locations, and for all types of point locations,
as described in section 4.4.3.
4.3.6 Urban
The values in this column indicate whether the traffic on the point location has a mainly
urban character (1) or inter-urban character (0)
4.3.7 Intersection reference
The intersection reference is a cross reference to a location code, representing the same
real world point location, but related to another road, if the locations are in the same
database, or to the same road in another database. If the location belongs to three or more
roads, cross-references are represented in the location table anti-clockwise in a circular way
(see table 4.2), such that each location code references only one other location code
explicitly, and the other(s) implicitly. The intersection reference has to include country code
and database number if it refers to another database.
Table 4.2 - Intersection reference - coding example
Location code Code of location . linear reference . intersection
(sub)type reference
1 L1.1
2 L1.1
3 L1.1
4P1.1 1 5
5P1.1 2 6
6P1.1 3 4
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4.3.8 WGS 84 co-ordinates
For each point location the WGS 84 longitude and latitude of the (approximate) centre of the
location shall be given (M), in decimal degrees with 5 microdegrees resolution, with a plus
sign (+) for eastern longitude and northern latitude, and a minus sign (-) for western
longitude and southern latitude. Degrees longitude are given in three digits (with leading
zeros if needed), degrees latitude in two digits (with leading zeros if needed).
Example +00435455 +5083940 represents 4°.35455 E 50°.83940 N
4.4 DETAILED JUNCTION REFERENCING
4.4.1 Conventional junctions
Lanes and slip roads are not individually numbered locations in ALERT-C. They are
addressed within the structure of ALERT-C messages (e.g. first exit; second exit; or 'for
traffic preceding towards '.)
4.4.2 Complex junctions
In more complex situations, parallel access roads and slip roads shall all be referenced as
slip roads or carriageways of the main highway, and shall not be coded as separate entries
in the location table.
4.5 DETAILED SITUATION LOCATIONS
4.5.1 Normal location referencing
In most TMC location tables, locations are pre-defined only at junctions and at other
prominent landmarks such as service areas; prominent, named tunnels and bridges; etc.
Where necessary, the detailed location of an accident shall in future be defined in the
message by its distance from the pre-defined primary location.
Where necessary, the end of the roadworks shall in future be defined in the message by its
distance from the TMC primary location.
Where necessary, the start of the roadworks shall in future be defined in the message by its
distance from the end of the roadworks. Some non ALERT-C protocols like DATEX already
allow precise distance indicat
...
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