宽码率Polar码浅海水声通信实验研究

Experimental Study on Shallow Sea Acoustic Communication with Multi-rate Polar Code

摘要:

浅海水声信道的随机时–空–频特性给数据的可靠传输带来了重大挑战，低复杂度和理论上证明能到达香农限的极化码(Polar code)可以增强水声通信系统的鲁棒性。水下传输的图像、语音、文本、海洋监测数据和遥控指令具有不等重要性的特点，宽码率 Polar 码能够适应不同水声信道和不等重要性的信息传输。 目前 Polar 码在水声通信中的实验研究多为仿真分析，设计了宽码率 Polar 码在厦门港海域海试验证，在不同信噪比的实录环境噪声下进行分析。海试结果表明：在良好的信道条件下，宽码率 Polar 码的性能优异，0.25 码率的 BPSK 和 QPSK 在实录环境噪声信噪比为–1 和 4 时实现零误码，其低复杂度信道编译码机制和宽码率与水声信道相匹配，可有效提高水声数据传输的可靠性和有效性，为基于 Polar 码的稳健可靠水声通信系统提供海试实验验证。

Abstract:

Shallow sea acoustic channels present random time-space-frequency characteristics，which brings great challenges to reliable data transmission. With low complexity and being theoretically proven that can reach the Shannon limit，polar codes can enhance the robust of underwater acoustic communication systems. Image，voice， text，ocean monitoring data and remote control commands are transmitted underwater with characteristic of unequal importance. The multi-rate polar codes can adapt to different underwater acoustic channels and information transmissions of unequal importance. At present，the application studies on polar codes in underwater acoustic communication are mostly simulation analysis. In this paper，a number of multi-rate polar codes are designed for the sea trial in Xiamen Port，as well as analysis under recorded ambient noise with different signal-to-noise ratios. The sea trail results show that under good channel conditions，the performance of the polar codes are excellent，with BPSK and QPSK with a bit rate of 0.25 achieving zero bit errors when the SNR of the recorded ambient noise is -1 and 4. The multi-rate polar codes with low-complexity channel encoding and decoding mechanism can match the underwater acoustic channel and effectively improve the reliability and effectiveness of underwater acoustic data transmission，and the robust and reliable underwater acoustic communication system based on polar codes is verified by sea trials.