Error probability performance of channel estimation error on cognitive multi relay networks

In this work, the system performance of a cognitive multi-relay amplify-and-forward network is investigated in the presence of imperfect channel estimations. In the proposed structure, the secondary source communicates with the secondary destination with the help of best relay and in the presence of imperfect channel estimations. The performance analysis for the proposed structure begins with the derivation of signal-to-noise ratio. Then, probability density function (PDF) and cumulative distribution function (CDF) are obtained. With the help of PDF and CDF, closed-form and asymptotic expressions of symbol error rate are derived and system diversity gain is obtained. Analytical results are verified with the simulations.