Linear Transceivers for Sending Correlated Sources over the Gaussian MAC

We consider the problem of sending two correlated ran-dom sources over a Gaussian multiple-access channel. The sources are assumed to be temporally memoryless. The performance criterion is the MSE and we seek lin-ear transceivers that minimize it. When the bandwidth expansion factor is unity, it is shown that uncoded trans-mission is the best linear code for any SNR. When the bandwidth expansion factor is two, we present a scheme that involves uncoded transmission of one source with ap-propriate power adaptation and uncoded transmission of the other source and its negative with appropriate power adaptation. This scheme is shown to strictly ourperform coding strategies based on TDMA. 1