Statistical Properties of Wireless Relay System with Correlated Diversity Channels

Relay systems are efficient transmission technique that can increase wireless network range, improve energy efficiency and lifetime of nodes in wireless sensor network. The main drawback of such systems is strong influence of bottleneck link on overall system performance. In order to improve the characteristics of bottleneck link, we consider additional techniques that can improve performance of a network as whole. In this paper we assume amplify-and-forward relay system with fixed gain amplification, operating in mixed Rice/Rayleigh fading environment. Since the first link is identified as bottleneck, implementation of polarization diversity at relay node is proposed. Two most important statistical functions of total received signal-to-noise ratio, probability density function and cumulative distribution function are derived. We also present system outage probability. The obtained results show that the location of relay node and implementation of polarization diversity can significantly improve system performance, with minimal system modifications.