Symbol error rate of QO‐STBC based decode‐and‐forward cooperative communication system over generalised – and – fading channels

Abstract

In this study, the authors derive the closed form expressions for symbol error rate (SER) of a quasi-orthogonal space-time block code (QO-STBC) based multi-relay cooperative communication system using M-ary phase-shift keying (M-PSK) modulation over generalised – fading channel. For the same system over – fading channel, due to the unobtainability of the closed form SER expressions, the analysis is restricted to binary-PSK and the bit error rate (BER) has been derived. The authors employ decode-and-forward protocol at the relays and maximal ratio combiner at the destination. For the ease of analysis, the authors consider a three relay cooperative network and the SER has been derived which could be extended to any number of relays or QO-STBCs. First, the expressions of SER were expressed in terms of moment generating function (MGF) and finally, the available closed form expression for MGF of – and – channel distributions are used to obtain the final expression of theoretical BER/SER. The validity of the obtained BER/SER expressions for a three relay cooperative system are verified through Monte–Carlo simulations by varying the channel parameters of – and – fading channels.