Polar Codes with Local-Global Decoding

TL;DR

This paper introduces a coupled polar code architecture enabling both local and global decoding, optimizing data recovery in storage and transmission with reduced latency and improved reliability.

Contribution

It proposes a novel local-global coupled polar code scheme with a systematic outer code and partitioned bit-channel mapping, enhancing sub-block access and overall error performance.

Findings

Error rate simulations for 2 and 4 sub-blocks demonstrate effectiveness.

Trade-offs between local and global decoding performance are analyzed.

The architecture supports practical applications requiring quick sub-block access.

Abstract

In this paper, we investigate a coupled polar code architecture that supports both local and global decoding. This local-global construction is motivated by practical applications in data storage and transmission where reduced-latency recovery of sub-blocks of the coded information is required. Local decoding allows random access to sub-blocks of the full code block. When local decoding performance is insufficient, global decoding provides improved data reliability. The coupling scheme incorporates a systematic outer polar code and a partitioned mapping of the outer codeword to semipolarized bit-channels of the inner polar codes. Error rate simulation results are presented for 2 and 4 sub-blocks. Design issues affecting the trade-off between local and global decoding performance are also discussed.