Empirical observations on wireless LAN performance in vehicular traffic scenarios and link connectivity based enhancements for multihop routing

In this work we assess the performance of a WLAN in different vehicular traffic and mobility scenarios. Furthermore, we investigate ad-hoc routing for a vehicular network. We deploy a topology consisting of vehicles bearing laptop computers equipped with IEEE 802.11b compliant equipment. Test scenarios for WLAN assessment are varied by conducting experiments under different vehicular mobility, peer-distance and driving environment conditions. The network throughput and the quality of the channel are observed to degrade with increasingly stressful communication scenarios. Based on empirical observations, we present results that can facilitate the development of efficient applications for inter-vehicular communication. To address multihop routing, we investigate and demonstrate the application of link connectivity assessment to efficient ad-hoc routing. A framework for enhancements is delineated and incorporated in the implementation of the optimized link state routing (OLSR) protocol. We demonstrate that the link quality assessment based enhancements improve the performance of OLSR.