Frequency-domain-equalization-aided iterative detection of faster-than-Nyquist signaling

A reduced-complexity three-stage-concatenated faster-than-Nyquist signalling (FTNS) based transceiver architecture is proposed, which operates with the aid of soft-decision (SoD) frequency-domain equalization (FDE) at the receiver. More specifically, the decoding algorithm conceived allows us to attain near-capacity performance as an explicit benefit of iterative detection, which is capable of eliminating the inter-symbol interference (ISI) imposed by FTNS. The proposed SoD FDE-aided FTNS detector has a low decoding complexity that increases linearly upon increasing the FTNS block length and is hence especially beneficial for practical long-dispersion scenarios. Furthermore, extrinsic information transfer (EXIT) charts are utilized for designing a near-capacity three-stage-concatenated turbo FTNS system, which exhibits an explicit turbo cliff in the low-SNR region, hence outperforming its conventional two-stage-concatenated FTNS counterpart.<br/

Faster-than-Nyquist Signaling for MIMO Communications

Faster-than-Nyquist (FTN) signaling is a non-orthogonal transmission technique, which has the potential to provide significant spectral efficiency improvement. This paper studies the capacity of FTN signaling for both frequency-flat and for frequency-selective multiple-input multiple-output (MIMO) channels. We show that precoding in time and waterfilling in space is capacity achieving for frequency-flat MIMO FTN. For frequency-selective fading, joint waterfilling in time, space and frequency is required.Comment: Have been submitted to IEEE transactions on wireless communication