Watermark-Based Code Construction for Finite-State Markov Channel with Synchronisation Errors

TL;DR

This paper introduces a new watermark-based coding scheme and decoder for finite-state Markov channels with synchronization errors, effectively accounting for channel memory and outperforming existing methods in high-capacity scenarios.

Contribution

A novel code construction and decoding approach that incorporate channel memory effects, improving synchronization error correction over traditional watermark schemes.

Findings

Proposed method rivals existing watermark decoders in performance.

Performs better when channel capacity exceeds 0.9.

Effective in channels with correlated memory effects.

Abstract

With advancements in telecommunications, data transmission over increasingly harsher channels that produce synchronisation errors is inevitable. Coding schemes for such channels are available through techniques such as the Davey-MacKay watermark coding; however, this is limited to memoryless channel estimates. Memory must be accounted for to ensure a realistic channel approximation - similar to a Finite State Markov Chain or Fritchman Model. A novel code construction and decoder are developed to correct synchronisation errors while considering the channel's correlated memory effects by incorporating ideas from the watermark scheme and memory modelling. Simulation results show that the proposed code construction and decoder rival the first and second-order Davey-MacKay type watermark decoder and even perform slightly better when the inner-channel capacity is higher than 0.9. The proposed system and decoder may prove helpful in fields such as free-space optics and possibly molecular communication, where harsh channels are used for communication.