Chinese Optics Letters

Performance analysis of LDPC code based on Watermark scheme in high-speed optical communication system

Wenxue He, Wenbo Zhang, Chao Li Chao Li, Lixia Xi Lixia Xi, Xiaoguang Zhang, Yaojun Qiao

Published Jan 1, 2015• 1 citation

Abstract

We study the decoding performance of low-density parity-check (LDPC) code based on Watermark scheme under different percentages of water-mark bits over 100 Gb/s differential quadrature phase shift keying (DQPSK) high-speed optical communication system. We also find the optimum percentage of water-mark bits according to the performance comparison. Simulation result shows an improvement of 0.5 dB net code gain by using the optimum Watermark scheme at a post-forward error correction bit error rate (BER) of 10-9, comparing with the traditional log-likelihood ratios belief propagation decoding algorithm. Also, for the same BER, there is a decrease in the number of iterations used in LDPC decoding.

DOI: 10.3788/col201513.s10601

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