Discovering the Unequal Importance of Coded Bits in the Decoding of Polar Codes

TL;DR

This paper identifies the most critical coded bits in polar code decoding and demonstrates that mapping these bits to reliable channels significantly enhances system performance, achieving up to 7 times better BER.

Contribution

It introduces a method to identify and map the most important coded bits in polar codes, improving decoding efficiency and system performance.

Findings

Up to 7x gain in BER performance with optimized bit mapping

Critical bits in polar decoding can be effectively identified using surrogate optimization

Mapping important bits to reliable channels enhances decoding success

Abstract

Polar codes are widely used in modern communication systems due to their capacity-achieving properties. This paper investigates the importance of coded bits in the decoding process of polar codes and aims to determine which bits contribute most to successful decoding. We investigate the problem via a brute-force search approach and surrogate optimization techniques to identify the most critical coded bits. We also demonstrate how mapping these important bits to the most reliable channels improves system performance with minimal additional cost. We show the performance of our proposed bit mapping in OFDM based systems, and demonstrate up to x7 gain in BER performance.