A Method of Wideband Signal Azimuth Estimation Based on Conditional Wavenumber Spectral Density

Abstract

The present invention proposes a method for estimating the orientation of a broadband signal based on conditional wavenumber spectral density, comprising: step 1) receiving a broadband signal of a long-distance target with a space line array, and performing a fast Fourier transform on the broadband signal in the time domain and the space domain , generate a space-time two-dimensional power spectral density function, and then use the ratio of the space-time two-dimensional power spectral density to the spectrum of the array receiving response as the conditional wavenumber spectral density, purify the extended conditional wavenumber spectral density spectrum, and obtain the purified spectrum of the conditional wavenumber spectrum ; Step 2) select the estimated scanning azimuth on the purification spectrum of the conditional wavenumber spectrum, calculate the peak energy position set in the strip corresponding to the estimated scanning azimuth, and use the least squares fitting to correct the estimated scanning azimuth , to obtain the corrected azimuth, and output the corrected azimuth and the corresponding peak energy to obtain an azimuth spectrogram, where the peak position on the azimuth spectrogram corresponds to the azimuth of the broadband signal. The orientation estimation accuracy of the present invention is high.

Description

technical field [0001] The invention belongs to the field of sonar digital signal processing, in particular to a method for estimating the direction of a broadband signal based on conditional wave number spectral density. Background technique [0002] Passive sonar detects targets and discriminates target types based on radiation noise. As one of the voiceprint characteristics of ships, broadband continuum describes the characteristics of ship radiation noise from the perspective of carrying energy in the frequency band. Detection has an integral role. The orientation estimation (Direction of Arrival, DOA) based on the sensor array is an important part of it, which faces problems such as limited array aperture, poor spatial resolution, and poor robustness to disturbance errors. [0003] At present, the algorithms for spatial direction finding of narrowband signals have become mature, but for wideband signals that carry more effective information and have higher application ...

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Problems solved by technology

[0007] The purpose of the present invention is to overcome the disadvantages of the existing high-resolution azimuth spectrum estimation algorithm, such as slow calculation speed, low feasibility, and the need to pre-estimate the number of sources and target azimuths in practical applications, the present invention proposes a Wideband Signal Direction Estimation Based on Conditional Wavenumber Spectral Density (CWSD-based) Method

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