Multipath utilization-based beam forming method

Abstract

The invention discloses a multipath utilization-based beam forming method. With the method adopted, the problem that multipath coherent signals cannot be effectively received in a low-altitude multipath environment in the prior art can be solved. The implementation process of the method includes the following steps that: an array radar acquires echo signal data, and solves a received signal covariance matrix Rxx; Toeplitz covariance matrix reconstruction is performed on the received signal covariance matrix, so that a new covariance matrix R is obtained; eigenvalue decomposition is performed on the reconstructed variance matrix, so that a noise subspace EN is obtained; a spatial spectral function S(theta) is formed according to the noise subspace; an angle corresponding to the peak value point of a spectral peak is found according to the spatial spectral function, namely the angle of a target is estimated; and with the estimated target angle adopted as a beam direction, beamforming isperformed. According to the method of the invention, with the estimated target angle adopted as the beam direction, beamforming is performed, and therefore, the multipath coherent information can be effectively utilized to improve the signal multi-noise ratio of echo signals. The method can be used for the effective reception of multipath coherent signals in a low-altitude multipath environment.

Description

technical field [0001] The invention belongs to the technical field of radar, and in particular relates to a beam forming method, which can be used for effectively receiving multipath coherent signals in a low-altitude multipath environment. Background technique [0002] When the radar is performing low-altitude detection, the echo signal not only includes the direct wave signal, but also includes the multipath wave signal. Under the influence of the multipath effect, the direct wave and the multipath wave are mutually coherent source signals, and the multipath coherent interference will cancel the desired signal, resulting in a sharp decline in the signal-to-noise ratio. The effect seriously affects the detection performance of low-elevation-angle targets. In order to solve this problem, the multipath interference beamforming algorithm has been widely studied. At present, according to the different processing methods for multipath interference, it can be divided into multi...

AI Technical Summary

Problems solved by technology

The joint reception of multipath signals is achieved by imposing the worst performance constraint on the desired signal and multipath interference, and it has good robustness, but the algorithm needs to estimate the direction of multipath interference, and there is a problem when the input SNR The problem of performance degradation and low output signal-to-noise ratio when increasing

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