Efficiency improvement of AODV for vehicular networks with channel availability estimation

Vehicular Ad-hoc Network (VANET) is the road vehicle´s communication network without a base station, which is proposed to utilize a link communication between vehicles according to IEEE 802.11p standard. For end-to-end communication between vehicles, a routing protocol is used to find a route based on link properties from one to another vehicle with specific requirements. In VANET, vehicles move at high speed, which makes topology changed all the time, often causing failures in data transfer. Additionally, the failures happen when the signal congestion is high in the VANET; the efficiency of data transfer therefore decreases. Thus, routing in VANET with high speed movement and high signal congestion is challenging. In this article, we present a cross-layer technique that calculates Channel Availability (CAV) at the link layer and applies CAV to AODV routing protocol to improve the communication for vehicle safety applications. We conduct our experiments on vehicular networks using NCTUns simulator with the realistic road-based mobility model. Our experiment results show the improvement on average TCP throughput and average UDP delay on different node density and data traffic density.