Efficient frequency‐domain linear distortion equaliser in faster‐than‐Nyquist systems

Abstract

Faster-than-Nyquist (FTN) signalling is regarded as a promising technology in satellite communications for the past few years, however, existing inter-symbol interference (ISI) elimination algorithms for FTN signalling cannot eliminate the linear distortion caused by the input-multiplexing and output-multiplexing filters, which are very common in satellite communications. On the strength of the fractionally-spaced equaliser (FSE), the authors propose a precoding-based frequency-domain linear distortion equaliser (PFLDE) to eliminate the above-mentioned linear distortion in FTN systems. On the one hand, by virtue of fast Fourier transform (FFT) and inverse FFT, the proposed PFLDE lends itself naturally to high-throughput parallel architectures, which are quite essential in high throughput satellite communications. On the other hand, the mean square error performance of the proposed PFLDE is superior to that of the existing time-domain FSEs. Furthermore, combining PFLDE with the existing ISI elimination algorithms for FTN signalling, the satisfactory bit error ratio performance can be obtained.