Layered source-channel coding for uniformly distributed sources over parallel fading channels

Abstract

In this paper, a robust and power-efficient transmission scheme of a time-discrete signal with continuous amplitude over parallel fading channels is proposed. A block of source samples is decomposed into N layers, so-called layered source coder. Each layer is transmitted over its own fading subchannel. The end-to-end mean square error (MSE) distortion, including distortion caused by the quantization process, the lossy compression, and channel errors, is adopted as the performance metric. We derive a power allocation strategy across the layers to minimize the end-to-end MSE distortion. The proposed transmission scheme gives higher robustness over the entropy-constrained source-channel coding scheme. In addition, the proposed transmission scheme requires much lower transmission power for a given source signal to noise ratio (SNRs) than the entropy-constrained scheme in the case of bandwidth compression. This power saving is meaningful for wireless communications with battery-operated devices.