Performance analysis of distributed Alamouti’s code for cooperative diversity networks

We analyze the bit-error rate (BER) performance of the distributed Alamoutipsilas code for cooperative diversity networks consisting of a source, two relays, and a destination node over Rayleigh fading channels. It is assumed that the relays use the amplify-and-forward protocol and that there is a direct path component. For M-pulse amplitude modulation (PAM) and M-quadrature amplitude modulation (QAM) constellations, we derive the exact BER expression with one integral. We also present a series expansion of a very accurate BER approximation, which does not require any numerical integration. Numerical results confirm that the exact BER expression with one integral perfectly matches the simulation results and the series expression of BER is very accurate, even with a small truncation window.