Average BER of BFSK with Postdetection Switch-and-Stay Combining in TWDP Fading

The performance of noncoherent binary frequency shift keying (BFSK) with dual-branch postdetection switch-and-stay combining (SSC) in two-wave with diffuse power (TWDP) fading is studied. A closed- form expression for the average bit error rate (BER) of noncoherent BFSK with dual-branch postdetection SSC is derived. Previously obtained results on the performance of predetection SSC in TWDP fading are corrected. The performance of postdetection SSC is compared to the performance of predetection SSC and it is shown that postdetection SSC outperforms predetection SSC. The effects of the fading parameters on the relative performances of the two SSC receivers are studied. Monte Carlo simulation results are presented to verify the validity of the obtained analytical results.