Environment Aware Virtual
Vehicle-to-Vehicle System Design
To ensure a robust automotive design against environment variations, a virtual software platform is key.
Dedicated Short Range Communications (DSRC) deployment is coming for vehicle-to-vehicle (V2V)
communications. Module vendors and vehicle system
integrators have commenced working in the design stage and
are finding a series of issues impacting their module design
or system integration that are out of their control (due to
environment variations affecting vehicles on the road).
The environment changes depend on where the vehicles
are located, i.e. rural, urban, or highway areas. In addition,
the DSRC IEEE 802.11P standard specifies the V2V
radio channel conditions include rural line-of-sight (LOS),
urban approaching LOS, street crossing non-line-of-sight
(NLOS), highway LOS, and highway NLOS.
Module vendors, car companies, and system integrators
must devise a way to put together systems that operate
with high connectivity and reliability in all these
environments. Ignoring this challenge prior to deployment
can cause market deployment delays and additional
implementation cost.
One way to address the above challenge is to have
design processes that can include a wide variety of
environmental scenarios, to ensure a robust design in
reducing the number of costly field road tests required.
To achieve this, we need a virtual software platform
emulating the environment, and meet the IEEE 802.11P
physical layer requirements. The good news is, this virtual
road test platform is already a reality.
Consider the radio channel for a pair of vehicles with
NLOS at a major street crossing (as seen in Figure 1).
Initially, the two cars don’t have communication until
they clear the corner building. Once this is completed,
performance challenges are primarily equated to the
distance between the cars, relative speed, and angle
between the vehicles. These physical parameters are
directly responsible for signal loss, delay, doppler shift,
etc. The communication system needs to overcome for
a reliable transfer of information. System designers are
then faced with the possibility of having to perform
field driving tests in many locations with non-repeatable
conditions. These include weather, total number of
vehicles, and interferers which are not controllable
and can vary significantly with time. Having a software
platform to emulate this in a virtual environment will help
pre-deployment design and integration of the different
modules and components for the V2V communication
system since all these variables can be controlled. A virtual
software strategy that includes IEEE 802.11P standard
compliant physical layer emulation will contribute to the
system design, making the design more reliable and robust.
Figure 1: Street crossing NLOS urban scenario.
The physical properties of the vehicle will also impact
the communication link. Consider the location of the
communication radio antenna on the vehicle. It’s worth
noting there’s a limited set of locations where the antenna
can be placed. Take for example, a dipole antenna which has
a typical radiation pattern as shown in Figure 2a. The same
antenna (when mounted on a car) will have the pattern
altered (as seen in Figure 2b) due to the presence of the
vehicle body. As the vehicle moves in the NLOS scenario
under consideration, the angle between the vehicles changes,
which in turn means the receive and transmit antennas line-of-sight angle also changes. As the angle shifts, so does the
overall antenna gain between transmitter and receiver. This
gain change would not occur if the perfect dipole antenna
pattern had been preserved once the antenna was mounted.
Antenna gain changes coupled to a communication channel
that’s also changing due to the relative movement of the
vehicles, means keeping track of all these dynamics—this
will involve more than just a classical channel link analysis.
A virtual scenario simulation platform allows for
capturing the physical 3D environment in which the