Research on Polar Coding Application for Underwater Acoustic OFDM Communication System

Abstract

This paper proposes a polar coding mechanism for the underwater acoustic (UWA) channel, which improves the performance in the bit error rate (BER) compared with the original code construction algorithms and decoding methods invented by Arikan. It studied the performance of polar coding in the UWA communication system with the Orthogonal Frequency Division Multiplexing (OFDM) technique in theory and simulation. The simulation results show that the BER of the polar code with the code rate 1/2 in the underwater time-varying channel can reach 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-4</sup> ~10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-5</sup> when the signal-to-noise ratio (SNR) is at 4 dB, which is about 0.5~1 dB better than LDPC and Turbo codes. Moreover, the BER performance of polar codes under different UWA channel models and parameters, code lengths, and code rates were also compared. The results demonstrate that the proposed mechanism matches the UWA channel well, thus making polar codes suitable and reliable for the UWA communication systems.