Performance analysis of a MMSE turbo equalizer with LDPC in a FTN channel with application to digital video broadcast

Faster-than-Nyquist (FTN) involves the transmission of information over the channel at a rate exceeding the inter-symbol interference (ISI) free rate proposed by Nyquist. FTN aims to increase channel capacity at a cost of inducing ISI. Effective use of FTN requires ISI mitigation to a level such that there is a net gain in capacity at a given SNR. Prior work demonstrated that a computationally-complex BCJR turbo-equalization scheme can mitigate ISI and result in a net gain. However, the BCJR is infeasible for practical applications where complex modulations are involved. In this work, we analyze the performance of a computationally efficient, MMSE-based, turbo-equalizer using a LDPC decoder with application to digital-video broadcast satellite channel and assess its ability to mitigate FTN induced ISI.