Traditional detection of broadband targets in passive sonars has low output signalto-noise ratio and poor performance in a complex situation with multiple targets and strong interferences. To solve this problem, this ...Traditional detection of broadband targets in passive sonars has low output signalto-noise ratio and poor performance in a complex situation with multiple targets and strong interferences. To solve this problem, this paper proposes a target detection method based on the characteristic of the energy distribution of broadband signals in the frequency-wavenumber domain by using uniform linear array. The proposed method converts the array signal into the frequency-wavenumber domain and uses the characteristics of the width and the spatial distribution of the main lobes and the side lobes to discriminate the main lobes in the wavenumber domain. After discriminating the main lobes of the same target at different frequencies, the accumulation of main lobe energy and the number of main lobes are used as the azimuth spectra for target detection. The theoretical analysis and simulations show the proposed method only utilizes the main lobes which have prominent contributions to target detection, thereby reducing the influence of the side lobes dramatically and improving the detection performance significantly. The results of trial data processing show that the output signal-to-noise ratio of the proposed method can be increased by 5.58 dB compared to SPED and 8.73 dB compared to CED. In addition, the computing time is decreased by 46% compared to CED, which validates the superiority of the proposed method.展开更多
The multi-beam DICANNE system has good performance for eliminating the strong interference. The theoretical basis of this digital system is presented in this paper, the steady state performance is discussed. The signa...The multi-beam DICANNE system has good performance for eliminating the strong interference. The theoretical basis of this digital system is presented in this paper, the steady state performance is discussed. The signal to noise ratio and signal to interference ratio is de rived. some principle for parameter selection in hardware designing is presented. The block diagram of this system is illustrated. The hardware implementation with DSP chip of TMS320 series is discussed.展开更多
基金supported by the Youth Science Fund Project (62001469)。
文摘Traditional detection of broadband targets in passive sonars has low output signalto-noise ratio and poor performance in a complex situation with multiple targets and strong interferences. To solve this problem, this paper proposes a target detection method based on the characteristic of the energy distribution of broadband signals in the frequency-wavenumber domain by using uniform linear array. The proposed method converts the array signal into the frequency-wavenumber domain and uses the characteristics of the width and the spatial distribution of the main lobes and the side lobes to discriminate the main lobes in the wavenumber domain. After discriminating the main lobes of the same target at different frequencies, the accumulation of main lobe energy and the number of main lobes are used as the azimuth spectra for target detection. The theoretical analysis and simulations show the proposed method only utilizes the main lobes which have prominent contributions to target detection, thereby reducing the influence of the side lobes dramatically and improving the detection performance significantly. The results of trial data processing show that the output signal-to-noise ratio of the proposed method can be increased by 5.58 dB compared to SPED and 8.73 dB compared to CED. In addition, the computing time is decreased by 46% compared to CED, which validates the superiority of the proposed method.
文摘The multi-beam DICANNE system has good performance for eliminating the strong interference. The theoretical basis of this digital system is presented in this paper, the steady state performance is discussed. The signal to noise ratio and signal to interference ratio is de rived. some principle for parameter selection in hardware designing is presented. The block diagram of this system is illustrated. The hardware implementation with DSP chip of TMS320 series is discussed.
