Estimation of target distance based on fractional Fourier transform analysis of active sonar linear frequency modulation signals

능동소나 linear frequency modulation 신호의 fractional Fourier transform 분석에 기반한 표적의 거리 추정

Hyung, Sungwoong;Park, Myungho;Hwang, Soobok;Bae, Keunsung

  • Received : 2015.10.08
  • Accepted : 2015.12.14
  • Published : 2016.01.31


As a generalized form of the conventional Fourier transform, fractional Fourier transform (FrFT) can analyze a signal at intermediate domain between time and frequency domains with a transform order ${\alpha}$. Especially, FrFT has a number of advantages in the analysis of LFM (Linear Frequency Modulation) signals due to its robustness to noise. In this paper, we have proposed a new method to detect and estimate the distance of the target from the FrFT spectrum of the received echo signal. Experimental results have validated the proposed method, and shown that reliable target distance could be estimated in noise and reverberation environments.


FrFT;Time-frequency domain;LFM;Active sonar;Target detection


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