Bit error rate of multi-node cooperative communications using Generalized Selection Combining over Rayleigh fading channels

Cooperative transmission is a recently developed concept which allows single-antenna devices to benefit from spatial diversity. This paper presents a multi-node cooperative communication protocol with an arbitrary N-relay nodes using selective Decode-and-Forward (DF) and Generalized Selection Combining (GSC) technique at each node in the network. Each relay or the destination will coherently combine the diversity paths with the largest instantaneous SNRs received from the source and its previous relays in the fashion of Maximal Ratio Combining (MRC) to achieve optimum performance within acceptable complexity and power consumption as well as extend network coverage. The exact closed-form analytical expression for the bit error rate (BER) is also derived to verify the validity of the proposed scheme under flat Rayleigh fading channel plus AWGN (Additive White Gaussian Noise). A variety of numerical results reveal that multi-node cooperative transmission is significantly better than direct transmission under the same transmitting power.