Performance evaluation of generalized selection combining over Nakagami fading channels

A performance analysis of the generalized selection combining (GSC) diversity scheme over Nakagami-m fading channels is presented. We show that by using the Dirichlet transformation, it is possible to derive a relatively simple expression for the moment generating function of the GSC signal-to-noise ratio output and to consequently develop a well-structured procedure for obtaining the average error rate in a form suitable for numerical evaluation. Numerical examples for several modulations of interest show that, for a fixed number of available diversity paths, the more severe is the fading the more diminishing are the returns obtained for an increasing number of combined paths. These numerical results also show that a significant performance improvement can be gained by increasing the number of available diversity paths for a fixed number of combined paths, especially for channels subject to low amount of fading