Window-based switch/selection diversity on correlated nakagami fading channels

A novel diversity combination that unifies the switch-and-stay combining (SSC) and selection combining (SC) is proposed, where a window with two decision thresholds is used for the switch/selection of diversity branches. At the beginning of a combining procedure, the branch with a larger signal-to-noise ratio (SNR) is selected as in the SC. If the SNR of the branch currently in use is larger than a preset high-threshold, the same branch is continuously used, while branch switching is activated once the SNR is lower than the preset low-threshold. In the meantime, the SC is employed if the used SNR is within the window formed by the two thresholds. With different combinations of threshold values, we can show that the SSC or SC is a special case of this window-based switch/selection combining (WSSC). The outage probability of the WSSC is derived and numerical results obtained from the analysis and simulations are presented for the performance illustration.