A method for eliminating co-frequency interference of external radiation source radar

Abstract

The invention belongs to the radar technology field and discloses an outer radiation source radar cofrequency interference elimination method. The method comprises steps that a reference signal received by a reference antenna and M echo signals received by an array element antenna are acquired; direct wave signals and multi-path signals of the M echo signals are eliminated by utilizing the reference signal to acquire M first echo signals, and an echo signal matrix is constructed; independent component analysis on the echo signal matrix is carried out to acquire three independent component signals; the three independent component signals are utilized to carry out three times of time domain interference elimination for the echo signal matrix to acquire three second echo signals; distance-Doppler two-dimensional correlation for each second echo signal and the reference signal is carried out to acquire three correlation matrixes, target detection is carried out by utilizing the correlation matrixes, second echo signals corresponding to the correlation matrixes of the target information can be acquired, namely echo signals after cofrequency interference elimination. The method is advantaged in that cofrequency interference in a main lobe can be effectively eliminated, and a relatively good target detection result is acquired.

Description

technical field [0001] The invention relates to the technical field of radar, in particular to a method for eliminating co-frequency interference of external radiation source radar. Background technique [0002] External radiation source radar uses a third-party radiation source signal (such as FM broadcast signal, analog TV signal, communication signal, etc.) as an illumination source to illuminate the target for detection, and its detection process is passive detection. Therefore, for external radiation radar, compared with interference and noise, its target echo signal is very weak, so the suppression degree of interference and noise will directly affect the detection performance of external radiation radar. [0003] Interference under the external radiation source radar system includes coherent interference and non-coherent interference. Among them, coherent interference refers to direct wave interference and multipath interference, and non-coherent interference refers t...

AI Technical Summary

Problems solved by technology

However, there are cases where the direction of arrival of the co-channel interference and the target echo are located in the same main lobe. In this case, the existing spatial filtering algorithm is no longer applicable.

For co-channel interference in the main lobe, there is no effective elimination method at present

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