Reliable geographic routing protocol for vehicular ad-hoc networks under shadowing and multipath environments

With the extensive adoption of Global Positioning System (GPS), geographical routing has received much attention from researchers all over the world. It is suitable for large-scale communication networks and offers promising solutions for information dissemination in the highly dynamic vehicular environment. Geographic routing employs greedy forwarding to transmit the data packets in a multi-hop manner. It selects a vehicle having minimum distance to the destination vehicle as the next forwarding vehicle (NFV). However, this packet routing approach fails in urban and highway environment. In this context, this paper proposes a reliable geographic routing protocol (RGRP) for vehicular ad-hoc networks under the combined impact of shadowing and multipath effects. RGRP selects an optimal NFV to transmit the data packet so that it reaches the destination vehicle efficiently and reliably. For NFV selection, it considers various routing metrics depicting link quality and node connectivity. RGRP also utilize Kalman filter to alleviate the impact of inaccurate location and high mobility on the performance of geographic routing. Through simulations, the performance of the RGRP is evaluated, and results show that the RGRP performance is encouraging when the objective is to maximize the reception of data packets at the destination vehicle.