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

Hyung, Sungwoong;Park, Myungho;Hwang, Soobok;Bae, Keunsung
형성웅;박명호;황수복;배건성

• Received : 2015.10.08
• Accepted : 2015.12.14
• Published : 2016.01.31
• 36 157

#### Abstract

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.

#### Keywords

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

#### References

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#### Acknowledgement

Supported by : 국방과학연구소