Technology Profile |
The tools needed
for C-ITS
302 637-2) describes the position,
speed and direction of a vehicle.
The message is regularly
emitted from vehicles between
1 to 10Hz.
• DENM: Decentralized
Environmental Notification
Message (ETSI EN 302 637-3)
describes the coding of hazard
warnings.
• IVI: In-Vehicle Information
(ISO 19321) regulates the coding
of traffic signs, including,
dynamic speed limit signage.
• SPAT/MAP (SAE-J2735
and ISO 19091): Signal Phase
and Timing can include both
the current signalling status and
its forecast. By referencing the
standardised description of the
intersection topology, it becomes
clear which signal group or
driving action the signalling
relates to. MAP displays lanes
and stop lines by means of
coordinate dots. Like all
messages, SPAT/MAP can
either be sent locally (useful
for applications that require
accurate and safe signalling
information) or transmitted
via the internet (useful for
the dissemination of forecasts
for certain applications.
At first, C-ITS was developed
for local communication (short
range). In a worldwide defined
frequency range of 5.9GHz,
vehicles and infrastructure
can directly communicate
with each other. A mobile
communications network is
not necessary for this. Part of
the road side unit is ideal for
this kind of communication
as the C-ITS complements the
infrastructure. On the vehicle
side, corresponding hardware
can be retrofitted. In the
VW Golf 8, it already comes
as standard.
Good communication
The first generation of shortrange
communication is called
Cooperative Intelligent
Transport Systems (C-ITS)
describe technologies and
standards to connect vehicles
with other vehicles (V2V) and
infrastructure (V2X). The idea
originated in the automotive
industry and aimed at
increasing road safety. However,
with the same standards,
a number of functions and
different tasks in traffic control
can be implemented.
With a single system you can:
prioritise rescue services and
public transport; better inform
road users, warn of hazards
as well as identify and count
vehicles and measure traffic.
Building blocks
C-ITS consists of several building
blocks. Decisive elements such
as message formats or
communication channels are
standardised. The devices, the
software and their integration
into existing technologies are
available on the market. The
most important elements are
listed in the following overview:
• CAM: The Cooperative
Awareness Message (ETSI EN
| Need to know
Opportunities and
developments in C-ITS
> Several OEMs are
integrating C-V2X or 5G
chipsets in their vehicles
> As well as providing
navigation, MAP can be
the foundation for new
functions
> Traffic signal control
offers multiple benefits
Above: Green light control
for firefighting vehicles
technological building block
in modern networked traffic
management.
Benefits from merely buying
and installing new hardware,
however, are limited. The full
benefit is only reached with
the right personnel employed
to use the technology.
Knowledge about connected
systems, IT security and the
protection of privacy in terms
of GDPR, critical infrastructures
or ISO27001 is also valuable.
Operators of traffic systems
have a strong starting point to
contribute to new applications
and thus to determine their
quality. So for example, every
traffic planner has the layout
of an intersection and the
corresponding signal program
with its signal groups at his
fingertips. From this he can
quite easily create a MAP.
Navigation map services are not
able to reach this level of quality
and accuracy.
Traffic Technology International March/April 2020
www.TrafficTechnologyToday.c 056 om
ETSI ITS G5 or 802.11p. A
subsequent generation is
known as C-V2X or PC5. Due
to integrated chipsets for C-V2X
and 5G mobile communication,
several carmakers plan
to equip their vehicles
with this technology.
In addition, the generated
messages can also be
transmitted via the internet.
The information made available
can then be sent via mobile
communication to the road
users. 5G promises more
bandwidth and secured
networks with guaranteed
availability and fast local
processing power.
Available today, 5G will
increasingly be an important
/www.TrafficTechnologyToday.c