Transmitter channel tracking for optimal power allocation

The design of accurate equalization schemes, optimizing the transmission strategy, can be achieved if channel status information is available not only at the receiver but also at the transmitter side. Accordingly, we propose a feasible scheme to track the channel response by the transmitter based on channel prediction, becoming a suitable solution in timevarying channels. Moreover, to follow faithfully the channel variability, the receiver can estimate the channel prediction error and next update the transmitter predictor through a return link. This paper, provides an accurate study of the predictor design, and analyzes the way to minimize the amount of information exchanged through the feedback channel concerning the di erential entropy of channel evolution. Furthermore, the prediction error is quanti ed focusing on the rate-distortion function, and it is shown that a low throughput is enough for tracking the channel coeÆcients even in the presence of fast time-varying channels.