Broad band coherent source azimuth estimating method based on data reconstruction

Abstract

The invention provides a broad band coherent source azimuth estimating method based on data reconstruction, which includes the steps as follows: (1) carrying out subband decomposition on the broadband array received data; (2) selecting the lowest frequency of the broadband signal as the focusing frequency and utilizing the spatial data construction formula to focus all the subband data on one frequency; (3) calculating the covariance matrixes of all the focused subband data, improving the covariance matrixes through the matrix conjugate rearrangement principle, and finding the mean value of the improved covariance matrixes of all the focused subband data as the final covariance matrix; (4) achieving the spatial spectrum estimation of the final covariance matrix through the MVDR algorithm, so as to obtain the azimuth information of the broad band coherent source. The broad band coherent source azimuth estimating method not only has higher angular resolution under low signal-to-noise ratio and less snapshots, but also can overcome the instability of the MVDR algorithm under the high low signal-to-noise ratio without the need of processing the angular resolution and the like; and the broad band coherent source azimuth estimating method has better azimuth estimating performance.

Description

technical field [0001] The invention relates to an array signal processing method. Specifically, it is a target orientation estimation method. Background technique [0002] Array signal processing technology based on high-resolution algorithms has always been a hot spot in scientific research. However, due to the variability of the ocean environment and the complexity of underwater acoustic channels, many classic subspace high-resolution algorithms have lost their original advantages and their reliability has declined. , the practicability deteriorates. The minimum variance distortion-free beamforming (MVDR) algorithm can provide the best signal protection, interference cancellation and noise reduction capabilities, and is more suitable for marine environments. In the actual marine environment, there are more and more situations where sonar receives broadband signals. Because of the large amount of information carried by the target echo and the weak correlation of the reve...

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