Low-complexity algorithm for FTN signal based on SOVA

Faster-than-Nyquist (FTN) signaling is a transmission method with high bit density and inevitable inter-symbol interference. Based on soft output Viterbi algorithm (SOVA), a low complexity receiver for FTN was introduced. The number of comparison in the backtracking process was adjusted by the result of survivor path and competitive path, and was reduced during the process. In application, a fixed backtracking length was searched and defined by statistical value, which was shorter than that in SOVA. The presented method reduces the complexity and time delay in the FTN signal detector. Without deteriorating bit error rate (BER), the number of comparison operations is reduced by 2/3, the number of registers is reduced by more than 50%, and the system delay is reduced by more than 50%.