An Iterative Decoder for Multicarrier Faster-Than-Nyquist Signaling Systems

An iterative decoder for time-frequency compressed multicarrier system is presented in this paper. The inner detector consists of a sub-optimal maximum a-posteriori symbol-by-symbol decoding algorithm with a successive interference cancellation (SIC) scheme. The complexity of the inner detector is not more complex than the corresponding detector for a memoryless modulation scheme. The inner decoder together with a standard BCJR forms the iterative decoding loop. The SIC scheme is used to eliminate the intentional interference caused by symbols stacked beyond their orthogonality limit. As compared to prior work, the iterative decoder has been adapted to make the FTN technique feasible for hardware implementation. The results show that such modifications does not affect the performance of the receiver. The receiver has been evaluated under various other FTN system parameters to determine the performance.