A novel normalized threshold generalized selection scheme and its performance evaluation

In this paper, we propose and analyze a new generalized selection combining (GSC) scheme referred to as N-branch plus normalized threshold generalized selection combining (N+NT-GSC). Performance measures are obtained through the derivation of the moment generating function (MGF) of the diversity combiner output signal-to-noise ratio (SNR) for generalized fading channels. Implementation complexity of N+NT-GSC is investigated, and the mean and variance of the number of combined branches are derived in compact forms. The new N+NT-GSC is shown to bridge the characteristics of normalized threshold generalized selection combining (NT-GSC) and the conventional GSC, and exhibit better robustness than previously proposed NT-GSC over branch imbalance and fading distributions.