Time Reversal and Fractional Fourier Transform-Based Method for LFM Signal Detection in Underwater Multi-Path Channel

Applied Sciences

Zhichen Zhang¹  Haiyang Yao¹  Haiyan Wang¹ 

[1] School of Marine Science and Technology, Northwestern Polytechnical University, Xi’an 710072, Shaanxi, China;

关键词: linear frequency modulation;    time-reversal;    fractional Fourier transform;    detection method;    underwater multi-path environment;   

DOI  :  10.3390/app11020583

来源: DOAJ

【 摘 要 】

Fractional Fourier transform (FrFT) is a useful tool to detect linear frequency modulated (LFM) signal. However, the detection performance of the FrFT-based method will deteriorate drastically in underwater multi-path environment. This paper proposes a novel method based on time-reversal and fractional Fourier transform (TR-FrFT) to solve this problem. We make use of the focusing ability of time-reversal to mitigate the influence of multi-path, and then improve the detection performance of FrFT. Simulated results show that, compared to FrFT, the difference between peak value and maximum pseudo-peak value of the signal processed by TR-FrFT is improved by 8.75 dB. Lake experiments results indicate that, the difference between peak value and maximum pseudo-peak value of the signal processed by TR-FrFT is improved by 7.6 dB. The detection performance curves of FrFT and TR-FrFT detectors with simulated data and lake experiments data verify the effectiveness of proposed method.

【 授权许可】

Unknown