LDPC encoding for partial-duplex wireless communication

Abstract

Low-density parity-check (LDPC) code is one of the fundamental error correction techniques used in wireless networks for achieving low probabilities of error. Wireless full-duplex (FD), according to its inherent nature, faces a considerable self-interference, which cannot be cancelled completely at the FD receivers. LDPC codes are excellent candidates for enabling full duplex in the presence of residual self-interference. This paper studies performance of a class of LDPC codes when the system faces a mixture of high and low bit SNR in the same codeword, condition associated with a scheme in which part of the bits is subject to FD interference (partialduplex scheme). In partial duplex (PD) schemes, part of the band is transmitted in FD and the rest in half-duplex and, consequently, some transmitted bits will be characterized by high SNR and the others by low SNR according to a pattern which is known, a-priori, by the system. Combining properly the patterns of these high and low SNR bits affects the coding performance of the system. In this study, we show the performance achieved by different strategies for allocating low SNR bits in the codeword of LDPC codes derived and adapted by the DVB-S2 standard.