Performance analysis of scaled switching technique for cooperative diversity systems

Diversity is one of the popular techniques to mitigate the adverse effects of fading. Among several diversity techniques, spatial diversity has attracted the researchers very much in recent times due its ability to support high data rate and superior reliability. A special form of spatial diversity known as distributed spatial diversity, which utilizes antennas of the distributed resources or nodes. The cooperation among the distributed antennas is studied in the cooperative diversity. We consider a cooperative diversity system with a source, a relay and a destination. The relay adopts decode and forward protocol. In this work, we present a hybrid diversity combining scheme which combines the ideas of switched diversity and scaled selection combining. We derive the end-to-end symbol error probability of this scheme with M-ary phase shift keying for a slow, flat Rayleigh fading environment. Numerical results show that the hybrid scheme performs better than the switched diversity, conventional selection combining and scaled selection combining.