Method for identifying frequency-shift interference of linear frequency modulated signal

Abstract

The invention discloses a method for identifying frequency-shift interference of a linear frequency modulated signal. The method comprises the following steps of: preprocessing the signals received bya radar, and dividing the signals into three paths before matching filters; passing the three signals through a complete matching filter and a designed half-bandwidth filter, and extracting a peak value of the output voltage of each half-bandwidth matching filter; setting a threshold; and determining whether the target is a frequency-shift interference false target according to the ratio of the matched output peaks of the target under different half-bandwidth matching filters and the set threshold. The invention has the following advantages: the radar can be used for real-time recognition ofmulti-targets; the application range is wide, and various false targets in an interference system can be identified; the shortcomings of the radar front-end tracking anti-interference method are compensated, and the detection and identification of the interference of an active advancing false target can be realized. The invention has few implementation steps and small calculation amount, can meetthe real-time identification of the radar for multiple targets, has no additional requirements on the hardware system, and is easy to implement in engineering.

Description

technical field [0001] The invention belongs to the field of radar anti-interference, and in particular relates to a method for identifying frequency-shift interference of linear frequency modulation signals. Background technique [0002] Chirp signal (also known as chirp signal abroad) is widely used in various pulse compression radars because of its long range and high range resolution. However, the coupling characteristics of its existing distance and Doppler frequency shift make the radar of this system extremely susceptible to frequency shift interference. Immediately after the frequency modulation signal, the frequency-shifting jamming technology will be used to generate long-distance realistic false targets in front of and behind itself, making it difficult for the radar to identify the real target. The target group will greatly consume radar resources. The major survival challenge faced by LFM radar makes it of great military application value to seek real-time and...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to provide a method for identifying frequency-shift interference of chirp signals, which solves the problem that the frequency-shift interference faced by chirp wideband radars has a large pulse pressure, and the generated false targets have high fidelity and are difficult to identify quickly and effectively. question

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