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

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.