Exact outage analysis of underlay cooperative cognitive networks over Nakagami‐ m fading channels

Abstract

This paper studies the outage performance behaviour of underlay cooperative cognitive networks over Nakagami‐ m fading channels. For time savings in collecting simulation results, the authors propose a new outage probability expression. Notably, this expression is quite general, taking into account practical operation conditions such as interference power constraint, maximum transmit power constraint, correlation among received signal‐to‐noise ratios, non‐identically and independently distributed Nakagami‐ m fading channels and the maximum ratio combining receiver. Moreover, it is useful in obtaining numerical results for performance comparison between dual‐hop communications and cooperative communications in underlay cognitive networks. Interestingly, analytical results illustrate that like dual‐hop cognitive networks, cooperative cognitive ones experience an error floor but the latter significantly outperform the former at almost no cost of power and bandwidth.