The Joint Detection to Underwater Moving Target’s LFM Echo Based on Matched Filter and Discrete Fractional Fourier Transform
Chen Peng①②; Hou Chao-huan①; Ma Xiao-chuan①; Liang Yi-hui③
①Institute of Acoustics,Chinese Academy of Sciences, Beijing 100080, China; ②Graduate School of Chinese Academy of Sciences, Beijing 100039, China; ③Ship Engineering Research Institute, Beijing 100036, China
Abstract：Matched filter is the optimal detector of LFM echo under the Gaussian white noise background, and the estimation of target range can be achieved according to the peak position of the matched filter’s output. The colored reverberation background and the mismatch between echo and replica caused by target’s radial velocity will both degrade the detection performance and the distance estimation precision. Combining the ranging property of matched filter and the focusing property of fractional Fourier transform to LFM signal, this paper proposes the joint detection method based on matched filter and discrete fractional Fourier transform. Simulation results show the joint detection method performs better than the pure matched filter, and the approximate estimation of target’s radial velocity can be obtained by the joint detection method.
2007, Vol. 29 
