A Study on Frequency Diversity for Intra-Vehicular Wireless Sensor Networks (WSNs)

Interest is increasing in the use of Wireless Sensor Networks (WSNs) for intra-vehicle network applications owing to the desire of manufacturers to deliver advanced in-car services. Operating WSNs in the unlicensed 2.4 GHz frequency band that is shared with other wireless technologies, e.g., Bluetooth and WiFi, brings additional challenges owing to interference and multipath fading. Therefore, a comprehensive understanding of the intra-vehicle wireless channel is essential for Radio Frequency (RF) resource allocation management, and to establish if various diversity techniques will assist in mitigating the effects of interference and fading in this environment. In this paper, we present our preliminary results in measuring the wireless channel for different scenarios within a car and also assessing the performance benefits that are potentially available from the use of Frequency Diversity (FD) for Line-of-Sight (LOS) and Non Line-of-Sight (NLOS) cases. A cross correlation based analysis of the results shows that FD offers a route to improve Intra-Vehicle Communication (IVC) quality by the use of smart frequency agile MAC protocols.