Analysis of generalized switch and examine combining (GSEC) over Rayleigh fading paths with unequal average SNR

In diversity-rich environments, there is a trade-off between performance and complexity. Optimal combining scheme, while delivering the best performance, introduces additional hardware complexity. Generalized switch and examine combining (GSEC) scheme was proposed as a low-complexity diversity technique for diversity-rich environments (H-C Yang and M-S Alouini, 2004). In this paper, we extend the study of GSEC to independent and non-identically distributed (i.n.d.) fading path environments. In particular, after discussing the mode of operation of GSEC over i.n.d. paths, we derive closed-form expression for the moment generating function (MGF) of GSEC combined SNR. We then apply it to analyze GSEC error performance in Rayleigh fading environments. Selected numerical examples are included to demonstrate various design tradeoffs.