Outer transmitter-based radar range migration compensation method based on frequency domain phase correction

Abstract

The invention relates to an outer transmitter-based radar range migration compensation method based on frequency domain phase correction and belongs to the technical field of radar target acquisition. The method comprises the steps that segment treatment is conducted on echo signals firstly; then echoes are converted to the frequency domain; phase correction is conducted on the echoes in the frequency domain to enable in-phase superposition of the signals to be achieved within the bandwidth and eliminate the influence of range migration; finally, the phase-corrected echoes are converted to the time domain through Fourier inversion, mutual ambiguity function calculation is conducted between the echoes and direct wave signals, and then a mutual ambiguity function diagram is obtained. According to the method, under the condition of a tracking mode (target speed is known) or that rough target speed is known, the accumulation gain of the method is similar to that of Keystone conversion, while the amount of calculation is far smaller.

Description

technical field [0001] The invention relates to a method for compensating distance migration of external radiation source radar based on frequency-domain phase correction, and belongs to the technical field of radar target detection. Background technique [0002] The external radiation source radar is a kind of bistatic (multi-base) radar, which uses the existing non-cooperative radiation sources (such as radio and television signals, etc.), and realizes the detection of the target by passively receiving the echo signal scattered by the target. as attached figure 1 shown. Since the target echo is usually weak, long-term coherent accumulation is required to improve the signal-to-noise ratio. In order to ensure the accumulation gain, it is required that within the coherent accumulation time, the range migration of the target cannot exceed one range unit. However, since the radar target echo from the external radiation source is very weak, it takes a long time to accumulate....

AI Technical Summary

Problems solved by technology

[0020] The purpose of the present invention is to solve the problem of distance migration caused by long-term accumulation when detecting weak echoes of targets, which is not conducive to target detection. A method for compensating range migration of external radiation source radar based on frequency domain phase correction is proposed. In the case of tracking (the target speed is known) or the approximate speed of the target is known, the long-term coherent accumulation of the external radiation source radar eliminates the target distance migration and improves the target accumulation gain

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