Distortion Exponent of MIMO Fading Channels

In this paper, we consider transmission of a continuous amplitude source over a quasi-static MIMO Rayleigh fading channel. The performance metric is end-to-end distortion of the source caused both by the lossy compression and the channel errors. We are interested in the high SNR behavior expressed in the distortion exponent, which is the exponential decay rate of the average end-to-end distortion as a function of SNR. Our goal is to maximize this distortion exponent by considering joint source and channel coding techniques. We provide digital strategies that utilize layered source coding coupled with multi-rate channel coding either by progressive or by superposition transmission, as well as a hybrid digital-analog scheme. When either the transmitter or the receiver has one antenna, we show that we are able to achieve the optimal distortion exponent.