Method and system for performing moving-target identification by using frequency-modulated continuous-wave radar

Abstract

The invention discloses a method and a system for performing moving-target identification by using a frequency-modulated continuous-wave radar. The method comprises the following steps of: acquiring difference frequency and modulation signals according to a radar signal at the current moment; acquiring distance information according to the difference frequency signal, wherein the distance information comprises a plurality of distance points and an amplitude value corresponding to each distance point; acquiring a Doppler frequency at the current moment according to the modulation signal; judging whether a moving target exists according to the Doppler frequency at the current moment; averagely processing background data to acquire background distance information; acquiring modified distance information by comparing the distance information at the current moment and the background distance information at the current moment; acquiring a moving target identification result by comparing the modified distance information and a threshold; and updating the background data by virtue of the distance information at the current moment when the moving target does not exist. According to the method and the system, the probability of mistaken reports can be reduced, and the accuracy of target identification is effectively improved.

Description

technical field [0001] The invention relates to a method and a system for recognizing a target by using a radar, in particular to a method and a system for recognizing a moving target by using a frequency modulation continuous wave radar. Background technique [0002] Compared with traditional pulse radar, frequency modulation continuous wave (FMCW: Frequency Modulation Continuous Wave) radar has low transmission power, low interception, small solid state, high distance resolution, large time bandwidth product, high sensitivity and high anti-active Interference ability and other advantages have been widely used in engineering. The basic working principle of FM continuous wave radar is to continuously and periodically modulate the frequency of the transmitted signal, and analyze the signal frequency at the time of transmission and reception, so as to obtain the relative distance and speed of the measured target. [0003] In order to detect dynamic objects in the defense zone...

AI Technical Summary

Problems solved by technology

Most of the surveillance sites in the civilian field are not quiet areas. The surveillance area may contain fixed objects such as walls, cables, and steel mesh, forming a complex area to be detected. The existing solution is to establish the background through environmental learning during the startup period. The environmental situation feedback is compared with the established background to determine whether there is a target. This method does not take into account the fluctuations of the transmitting and receiving power and the fluctuation of the background. Practice shows that the establishment of a fixed background environment cannot truly reflect the movement of the target. And the false alarm rate is high due to background fluctuations

That is to say, the radar system that establishes a fixed background through power-on learning is suitable for a relatively stable and simple detection environment. If the fixed background is still used as a reference in a complex environment, factors such as background fluctuations, multipath reflections, and environmental energy superposition will affect The background information at the time of detection is quite different from the background at the time of initial establishment, resulting in false positives, missed negatives, and false positives

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