An exact analysis of the impact of fading correlation on the average level crossing rate and average outage duration of selection combining

This paper derives the average level crossing rate (LCR) and the average outage duration (AOD) of selection combining (SC) over correlated and/or unbalanced channels. More specifically, it presents a general approach for the analysis of such systems operating over correlated Rayleigh, Rician, and/or Nakagami fading channels. The general approach is then applied to obtain generic closed-form expressions for the LCR and AOD of dual-branch SC in a correlated Rayleigh and Nakagami fading environment. The results obtained as special cases of the offered generic closed-form expressions are compared to those previously reported in the literature. Finally, some numerical examples comparing the LCR and AOD of SC with various value of fading correlation, average fading power unbalance, and Nakagami parameter are provided and discussed.