Switch-and-stay partial relay selection over Rayleigh fading channels

In this study, a switch-and-stay partial relay selection (SS-PRS) scheme is analysed, where only a single relay from two cooperating open-form decode-and-forward (DF) relays is active in each transmission time slot. The performance of the proposed relay selection scheme is presented in terms of the outage probability and the average bit error rate (ABER). In this study, closed-form expressions are derived for the outage probability and the ABER of the system. In addition, an optimum threshold for the relay switching is found in a minimum ABER sense for the binary phase-shift keying modulation. The numerical and analytical results show that the SS-PRS scheme and the conventional PRS scheme give almost the same performance, whereas the SS-PRS has the advantage of notably lower complexity.