Design of Multilayer Coded Modulation for Nonergodic Block-Fading Channels

Abstract

Multilayer coded modulation (MLyC) in single-antenna and multiple-antenna wireless fading channels is investigated. While the MLyC has been known to achieve ergodic fading channel capacity, the problem of interest here is to design practical and efficient MLyC for nonergodic block-fading channels. We develop a design methodology which maximizes the information rate of MLyC, subject to an upper bound on the decoding error probability. Moreover, we show that the MLyC performs closer to channel capacity when the overall diversity order of the channel is higher and proper spatial interleaving is employed. The relationship between the MLyC scheme and other transmission techniques, such as multilevel coded modulation and bit-interleaved coded modulation (BICM), is also discussed. It is shown through simulation examples that in realistic block-fading channels, the MLyC with practical coded modulation outperforms the BICM without turbo receiver iteration. We propose the MLyC as a promising alternative to BICM, especially when turbo iterative processing is not desired, e.g., for progressive layered media transmission