Baseband Transmission on Power Line Channels with LDPC Coset Codes

High rate transmission over power lines imposes stringent requirements in coding and equalization, the chief impairments being severe signal attenuation and impulsive noise. Yet, transmission requirements over this medium have reached several Mbit/sec to compete with other types of access. In this paper, we propose a novel PAM-based coded modulation scheme that is well suited to meeting such constraints. The proposed scheme combines Low Density Parity Check (LDPC) codes and maximum-distance separable block codes to achieve high spectral efficiency, low decoding complexity, and a high degree of immunity to impulse noise. To achieve better immunity to burst and impulse noise, a novel interleaving scheme is proposed. To achieve good performance in the presence of inter-symbol interference, the proposed coset-coding is combined with Tomlinson-Harashima precoding and spectral shaping at the transmitter.