Analysis of the Impact of Wireless Three-User Multiple Access Channel Coefficients Correlation on Outage Probability: A Copula-Based Approach

In wireless communication channels, the channel coefficients are dependent on each other. This paper investigates the constructive or destructive effects of fading coefficients correlation of wireless multiple access channels (MAC) on the outage probability (OP) (one of the wireless communications performances). The desired channel in this paper is a wireless Rayleigh fading MAC with three-users, independent sources, and interdependent fading coefficients; The Copula theory is used as the tool to model the dependence structure. A closed-form expression for the channel outage probability is obtained using an important family of Copulas named the Farlie-Gumbel-Morgenstern (FGM) Copula. The results show that the negative dependence structure of the channel coefficients has a constructive effect on the outage probability; in other words, it reduces the outage probability values compared to the independent case. in contrast, the positive dependency has a destructive effect on the outage probability. The efficiency of the analytical results is illustrated numerically, and the numerical illustrations confirm the theoretical results.