A PAPR Reduction scheme Based on Nonlinear Companding Transform and LDPC-coded for a Coherent Optical GFDM system

Abstract

A P APR reduction method based on nonlinear-companding-transform (NCT) and LDPC-coded is proposed to reduce high P APR of GFDM systems. This scheme utilizes the performance complementarity of NCT and LDPC-coded to effectively achieve superposition of advantages. An 80-Gbaud PDM-CO-GFDM system employing the proposed scheme is set up. When CCDF is 1e-2 and $\mu$ is 2, P APR is reduced by 5.16 dB compared with original GFDM scheme (GFDM-LDPC scheme). When BER is 1e-2, OSNR is reduced by 3.1 dB compared with original GFDM scheme, 3.9 dB compared with GFDM-NCT scheme, -0.5 dB compared with GFDM-LDPC scheme. Simulation results show that the proposed scheme has better performances in reducing the P APR and BER for GFDM.