Hybrid Digital-Analog Communication of a Bivariate Gaussian Source over a Fading MAC

We consider the problem of sending a bivariate Gaussian source over a slow-fading multiple-access channel (MAC) with no channel state information at the transmitters. A joint source-channel coding (JSCC) scheme is constructed using hybrid digital- analog (HDA) coding techniques to minimize the average distortion over the uncertain MAC. Numerical results show that, under Rayleigh fading, the proposed HDA scheme can outperform the source-channel separation approach and the uncoded approach as the power-to-noise ratio increases. A HDA scheme based on orthogonal multiple access is designed for comparison.