On cooperative source transmission with partial rate and power control

The problem of transmitting a Gaussian source over a half-duplex fading relay channel with limited channel state feedback is studied. It is shown that under a short-term power constraint, combining a simple feedback scheme with separate source and channel coding outperforms the best known no-feedback strategies even with only a few bits of feedback information. Partial power control is shown to be instrumental in achieving a very fast decaying average distortion, especially in the regime of high bandwidth ratios. Performance limitation due to the lack of full channel state information at the destination is also investigated, where the degradation in terms of the distortion exponent is shown to be significant. However, even in such restrictive scenarios, using partial feedback still yields distortion exponents superior to any no-feedback schemes.