Method for improving low interception and interference resistance of radar

Abstract

The invention relates to a method for improving low interception and interference resistance of a radar, which comprises the steps of constructing a frequency agile transmitted signal, performing pulse compression processing on a received echo signal, performing frequency agile signal phase cancellation processing, and performing frequency agile signal detection fusion processing. According to the method, every two adjacent target echoes after pulse compression are conjugated and multiplied, so that a phase interference term coupled with the number of transmitted pulses, the pulse transmitting time, the target distance and the speed in an echo signal is changed into a constant phase term, coherent processing and target detection can be further realized, and the adaptability of the algorithm is improved. Meanwhile, the method can realize coherent processing of echo matrixes of two frequency agile models, can realize fusion detection of detection results, and improves the anti-interference performance and adaptability of a signal processing algorithm. The method is suitable for low, medium and high repetition frequency modes, and has good expansibility.

Description

technical field [0001] The invention relates to the technical field of radar anti-jamming, in particular to a method for improving low interception and anti-jamming performance of radar. Background technique [0002] With the development of radar technology, radar jamming technology has also achieved a qualitative leap, gradually developing from the traditional rough jamming mode to distributed, smart, compound and adaptive jamming, which has brought great harm to radar. . [0003] In view of the real threat brought by the development of jamming technology to radar, since the birth of radar, the research on radar anti-jamming technology has not stopped, including airspace anti-jamming measures, frequency anti-jamming measures, signal processing domain anti-jamming measures, etc. In recent years, driven by the increasingly complex reality of interference and target environments, radar anti-jamming technology has made great progress. Typical technologies include new ultra-low...

AI Technical Summary

Problems solved by technology

Pulse group agility radar still has the characteristics of pulse group operation, and it is still easy to be detected and interfered, and the anti-jamming effect is limited.

Due to the random frequency agility of inter-pulse random frequency radar, the low interception performance and anti-interference performance of the radar are improved, but the relative movement between the target and the radar and the frequency of agility will make the radar echo signal have frequency and target distance and The problem of speed coupling makes the traditional coherent processing algorithm no longer applicable, which brings challenges to the application of pulse-to-pulse random frequency-agile technology in radar

In view of this problem, the existing literature mostly adopts high repetition frequency frequency stepping technology, uses the same frequency pulse sequence for coherent processing, frequency stepping signal to obtain high-resolution signal of distance, or uses speed estimation method to perform target speed and frequency coupling item Most of these methods ignore the influence of distance and frequency coupling items on coherent processing performance, or only perform coupling of speed and distance by distance unit under the condition of achieving high distance resolution.

The above methods need to work in the high-repetition frequency mode, and it is necessary to obtain the high-resolution range image of the target first, so that it is possible to realize the coupling compensation of speed, distance and frequency, and there are serious problems of distance ambiguity and distance occlusion, which have great limitations. , the above factors restrict the practical application of related technologies in radar

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