Joint source and channel coding using a non-linear receiver over Rayleigh fading channel

This paper considers the joint optimization of the source and channel coders over a Rayleigh fading channel. The system being investigated consists of a vector quantizer (VQ) whose output indices are mapped directly into points in the modulation signal space. The modulation signal is then transmitted over a Rayleigh fading channel. A decoder based on a nonlinear estimator is used to reconstruct the source signal from the received signal samples and from the channel state information (CSI). The paper presents an iterative algorithm that jointly optimizes the vector quantizer and the modulation signal set using as optimality criterion the minimum mean-square error (MSE) between the original and the reconstructed signals. It is shown that a jointly optimized system based on average channel characteristics significantly outperforms a reference system based on a VQ designed for the given source and a standard QAM modulation signal set