Effect of macrodiversity on outage probability and average channel capacity in composite Nakagami-gamma environment

In this paper, the performance of wireless communication system with micro- and macrodiversity reception over channels subjected to Nakagami-m fading and gamma shadowing is investigated. Microdiversity reduces the effect of short-term fading while macrodiversity reduces shadowing (long-term fading) effect. N-branch maximal-ratio combining (MRC) is implemented at the micro level and dual diversity selection combining (SC) is implemented at the macro level. Analytical expressions for the probability density function (PDF) and cumulative distribution function (CDF) of signal after micro- and macrodiversity processing are derived and used to study important system performance criteria such as the outage probability and average channel capacity. Numerical results are graphically presented to show enhancement due to use of the combination of micro- and macrodiversity, as well as the effects of various system and channel parameters to the system performance.