Velocity ambiguity resolving method based on coherent frequency agile radar

Abstract

The invention discloses a velocity ambiguity resolving method based on a coherent frequency agile radar. Through the method, the problem that target detection is not accurate due to distance-velocityambiguity in pulse radar system signal processing is solved. According to the implementation method, a radar pulse echo signal is received; a baseband pulse echo signal sampling matrix is obtained; pulse compression is performed; a radar Doppler vector group is constructed; Doppler offset frequency is determined, and the velocity of a motion target is calculated; velocity ambiguity resolving is performed on the radar pulse echo signal; and target detection is performed through sparse recovery. According to the method, the accurate velocity of the motion target is calculated through the Dopplervector group, velocity phase compensation is performed on the radar pulse echo signal to realize velocity ambiguity resolving, and the target is detected through sparse recovery. The method is low ininterception and resistant to interference, the velocity of the motion target can be accurately calculated, complexity is low, and the problem of distance-velocity ambiguity in pulse radar system signal processing can be solved. The method is applied to the field of radar target detection.

Description

technical field [0001] The invention belongs to the technical field of radar signal processing, relates to the range-velocity ambiguity problem existing in the pulse radar system, and specifically relates to a velocity defuzzification method based on coherent frequency agile radar, which can be applied to target detection. Background technique [0002] Since the carrier frequency change of traditional LFM radar and step frequency radar is linear, the phase change law of radar echo caused by carrier frequency change and the phase change law caused by target movement are both linear, so the distance and speed are mutually coupled , there is a range-velocity ambiguity problem, see image 3 , which greatly reduces the detection ability of the target. Therefore, it is an important development direction in radar signal processing to solve the range-velocity ambiguity problem of the pulse radar system to improve the detection ability of the target. [0003] Xi'an Space Radio Techn...

AI Technical Summary

Problems solved by technology

The disadvantage of this method is that the pulse pressure judgment threshold needs to be calculated after pulse compression. On the one hand, it increases the computational complexity; on the other hand, if the threshold calculation is inaccurate, it will affect the target detection result.

The disadvantage of this method is that in the process of looking up the table, it is necessary to make a difference between the input target velocity channel signal and the target velocity in the two-dimensional velocity defuzzification table row by column, which results in a large amount of calculation, slow table lookup speed and low efficiency.

[0005] It can be seen from the prior art that the current methods to solve the radar range-velocity ambiguity problem have problems such as large amount of calculation and inaccurate target detection results, which will affect the calculation efficiency of radar signal processing and target detection results.

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