Average level crossing rate and average outage duration of switched diversity systems

This paper presents closed-form expressions for the average level crossing rate (LCR) and average outage duration (AOD) of switch and stay combining (SSC). The results are quite general and applicable to dual-branch systems operating with equal/unequal thresholds over independent generalized fading paths which are not necessarily identically distributed. It is shown that our general results reduce to the specific case previously published. These new expressions are compared to those previously reported in the literature dealing with the LCR and AOD of selection combining (SC). Corresponding numerical examples and plots are also provided and discussed. These plots show that for a suitable choice of the switching threshold, SSC provides a lower AOD than SC but at the expense of a higher LCR or equivalently frequency of outages.