# Improved decoding and error floor analysis of staircase codes

**Part of the following topical collections:**

## Abstract

Staircase codes play an important role as error-correcting codes in optical communications. In this paper, a low-complexity method for resolving stall patterns when decoding staircase codes is described. Stall patterns are the dominating contributor to the error floor in the original decoding method. Our improvement is based on locating stall patterns by intersecting non-zero syndromes and flipping the corresponding bits. The approach effectively lowers the error floor and allows for a new range of block sizes to be considered for optical communications at a certain code rate or, alternatively, a significantly decreased error floor for the same block size. Further, an improved error floor analysis is introduced which provides a more accurate estimation of the contributions to the error floor.

## Keywords

Staircase codes Coding Error floor FEC for optical communications## Mathematics Subject Classification

94B05 94B35## Notes

### Acknowledgements

The authors would like to thank Gerhard Kramer and Frank Kschischang for the valuable discussions and the anonymous reviewers for their comments that helped improve the quality and presentation of this work.

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