Outage and BER Performance Analysis of Cascade Channel in Relay Networks

In this paper, the outage and bit error rate (BER) performance of a relay networks is studied based on the cascade channel. Firstly, the distribution of the cascade channel, which is the integration of L double-Rayleigh complex random variables (RV), is derived in close form. To overcome the computational difficulty of the arising special function, the probability density function (pdf) of the channel is approximated by the concise Gamma distribution. Through matching the moments of both pdfs, the corresponding shape and scale parameters of the Gamma pdf are obtained. Based on the pdf approximation, the closed-form and accurate expressions of the metrics: outage probability and BER of the cascade channel, are deduced. Numerical results illustrate the accuracy of the proposed performance evaluation.