Abstract
In this study, under imperfect channel state information in Rayleigh fading channels, the authors analyse a previously proposed distributed turbo coded cooperative scheme based on parallel concatenated convolutional codes and soft‐decode‐and‐forward mode. For coherent binary phase shift keying over independent Rayleigh fading channels, the authors assume that the imperfect estimation errors are Gaussian distributed having a variance equal to a fraction of the variance of normalised Rayleigh distribution. Using the transfer function approach, the authors define an upper bound of the pairwise error probability to compute the average union upper bound for the bit error probability.