Performance Analysis of Bidirectional AF Based Cooperative Vehicular Networks

This paper studies the precise performance of bidirectional amplify and forward (AF) based cooperative vehicular communication networks operating over cascaded Nakagami-m fading environments with arbitrary positive real numbers m, which have been proposed to be a realistically good description of the physical layer channel model of vehicular networks. Exact expressions are derived for four significant performances, namely moment generating function (MGF), higher order moments of signal to noise ratio (SNR), ergodic capacity and average symbol error probability (SEP), whose closed solutions have not been publicly reported. In order to obtain these accurate expressions, we turn our eyes to the MGF of inverse SNR instead of the usual probability density function (PDF) and cumulative distribution function (CDF), which are unknown and difficult to acquire, as well as fail in deriving closed form solutions. Simulation results corroborate the correctness and tightness of the derived expressions, sharp contrast to the approximations and asymptotic values at a sufficiently high SNR region in previous works.