Packet combining for multi-layer hybrid-ARQ over frequency-selective fading channels

For reliable data transmission using single-carrier signaling over multi-path fading channels, multi-layer hybrid automatic repeat request (HARQ) protocols is a promising technique for high data throughput communication systems. In this paper1, we propose a joint equalization scheme for multilayer packet retransmission over a frequency-selective fading channel. We first derive the equivalent MIMO channel model for multi-layer retransmission. Then, we present the corresponding receiver implementing a successive interference cancellation scheme with integrated joint equalization for each layer. We evaluate, by computer simulations, the frame error rate performance and the throughput performance of a retransmission based multi-layer HARQ protocol using the proposed combining scheme. Simulation results show a significant performance gain in comparison with post-combining methods based on separate detection and packet combining at the bit level.