An Iterative Receiver for Coded Faster-than-Nyquist Signaling over Rayleigh Fading Channels

In this paper, we propose a novel iterative receiver for the coded faster-than-Nyquist (FTN) system over multipath Rayleigh fading channels, where the receiver processing can be described by a multi-layer structure. Specifically, the successive interference cancellation is adopted among different layers to eliminate the multipath interference, while a carefully designed truncated BCJR algorithm based on the Ungerboeck model is utilized to deal with the inter-symbol interference for each layer. Furthermore, we derive a concise graphical model to describe the proposed FTN receiver and further introduce a novel iterative strategy according to the message passing framework. Simulation results show that the proposed receiver can successfully recover the FTN signal under various channel conditions, and demonstrate that the FTN system has good diversity potential. In particular, compared to the Nyquist system, the proposed FTN receiver is able to attain 25% spectral efficiency gain at the cost of negligible frame error rate loss.