Abstract:
In a VANET vehicles communicating with each other and infrastructure is the basis of the future
of vehicular transportation. There are several applications of a VANET. The most important
application in VANETs is safety application. Basic Safety Messages exchanged between vehicles
can be lifesaving. Though, if safety messages are not received in a timely or reliable way, a safety
application's efficiencies could suffer. One of the main challenges for communication in VANET
is well-organized network channel utilization for the transmission of packets. Regularly
transmitting packets at a fixed transmission power without taking into consideration the traffic
density, current channel load, transmission delay, vehicle speed, etc. is highly inefficient and will
lead to a high number of packet collisions on the channels. With the increasing number of vehicles
in the vehicular network, the number of safety messages also increases quickly, which results in
network channel congestion.
This paper introduces a congestion control approach by adapting transmission power based on
vehicle density and vehicle speed. By this approach, Vehicles will broadcast packets at suitable
transmission powers. The goal is to reduce congestion on the network channel and advance the
network’s overall performance. The proposed algorithm was applied in a simulation environment
and its performance was validated in various traffic scenarios. The research was conducted using
OMNET++, Veins, and SUMO. Our simulation results show that this method can lead to
improving performance in terms of reduced packets lost, beacon error rate, and channel busy time
thus increasing the performance of VANET.