On Parameter Optimization and Reach Enhancement for the Improved Soft-Aided Staircase Decoder

TL;DR

This paper optimizes the parameters of the iSABM-SCC algorithm for staircase codes in fiber optics, significantly reducing the gap to theoretical limits and increasing fiber reach by up to 22%.

Contribution

It provides a detailed parameter optimization and performance analysis of the iSABM-SCC decoder, enhancing its effectiveness in optical communication.

Findings

Reduced gap to achievable information rates to 0.26-1.02 dB.

Achieved up to 22% fiber reach increase.

Optimized thresholds improve decoding performance.

Abstract

The so-called improved soft-aided bit-marking algorithm was recently proposed for staircase codes (SCCs) in the context of fiber optical communications. This algorithm is known as iSABM-SCC. With the help of channel soft information, the iSABM-SCC decoder marks bits via thresholds to deal with both miscorrections and failures of hard-decision (HD) decoding. In this paper, we study iSABM-SCC focusing on the parameter optimization of the algorithm and its performance analysis, in terms of the gap to the achievable information rates (AIRs) of HD codes and the fiber reach enhancement. We show in this paper that the marking thresholds and the number of modified component decodings heavily affect the performance of iSABM-SCC, and thus, they need to be carefully optimized. By replacing standard decoding with the optimized iSABM-SCC decoding, the gap to the AIRs of HD codes can be reduced to 0.26-1.02 dB for code rates of 0.74-0.87 in the additive white Gaussian noise channel with 8-ary pulse amplitude modulation. The obtained reach increase is up to 22% for data rates between 401 Gbps and 468 Gbps in an optical fiber channel.