Analog Joint Source Channel Coding for Gaussian Multiple Access Channels

We investigate the problem of transmiting independent sources over the Gaussian Multiple Access Channel (MAC) using a CDMA-like access scheme that allows users to transmit at different rates. Rather than using standard digital communications systems, we focus on analog joint source-channel coding techniques to encode each user’s source. We analyze the performance of the proposed scheme and demonstrate its optimality. Simulation results with practical analog joint sourcechannel codes optimized for point-to-point communications show that the resulting performance is very close to the theoretical limits.