Interference suppression method based on low-correlation space-time two-dimensional random directional diagram

Abstract

The invention discloses an interference suppression method based on a low-correlation space-time two-dimensional random directional diagram. A space-time two-dimensional random directional diagram inmicrowave staring super-resolution imaging is designed, and interference can be more effectively suppressed. The method comprises the steps of generating an orthogonal random phase sequence based on agenetic search algorithm, establishing a phased-array antenna working coordinate system for representing an array element position, calculating a phased-array far-field directional diagram function by utilizing the generated orthogonal random phase sequence, and identifying a target and interference of an array element signal in combination with a sparse reconstruction algorithm. According to theinvention, the random initial phase of the array element signal is generated by using a genetic search algorithm; the designed directional diagram has better orthogonality and performance, the orthogonality of the designed directional diagram is better, target signals and interference signals are separated through matched filtering at the receiving end of the phased array radar, and interferenceof array element signals can be suppressed more effectively. The method is used for anti-interference for radar signals.

Description

technical field [0001] The invention belongs to the technical field of signal processing, and in particular relates to radar pattern design, specifically an interference suppression method based on a low-correlation space-time two-dimensional random pattern, which is suitable for low-intercept electronic reconnaissance in an interference environment. Background technique [0002] The phased array antenna is composed of multiple antenna units, and each antenna is equipped with a phase shifter, which is used to change the phase relationship of the signals between the antenna units and realize electronic beam scanning. The pattern of the traditional planar phased array radar is a sinc function, with a main lobe and multiple side lobes. The pattern has strong regularity, so it is easy to be intercepted by enemy reconnaissance planes. [0003] At present, radar imaging technologies mainly include optical imaging, real aperture radar imaging, synthetic aperture radar imaging, inve...

AI Technical Summary

Problems solved by technology

The pattern of the traditional planar phased array radar is a sinc function, with a main lobe and multiple side lobes, and the pattern has strong regularity, so it is easy to be intercepted by enemy reconnaissance planes

[0003] At present, radar imaging technologies mainly include optical imaging, real aperture radar imaging, synthetic aperture radar imaging, inverse synthetic aperture radar imaging, correlation imaging, etc. These technologies have developed rapidly in recent years, but they also have their own defects: infrared imaging The working distance is relatively short; real-aperture radar imaging cannot obtain a large-aperture antenna that meets high resolution; synthetic aperture radar and inverse synthetic aperture radar are based on coherent processing methods that are vulnerable to threats of reconnaissance and interference, and depend on the relative motion of the radar and the target Correlation imaging generally requires the use of pseudothermal light to participate in the imaging process, and requires pseudothermal light to have the characteristics of random fluctuations in time and space, and a new method of microwave staring imaging based on space-time random radiation fields proposes a space-time random radiation field Pseudothermolight

[0005] Wang Jingru et al. published in 2017 "Analysis on the Method of Constructing Random Radiation Fields for Radar Correlation Imaging" proposed a random pattern construction method based on random frequency-hopping pulse signals. The frequency-hopping bandwidth of this method is too large, and the practicability is not strong

[0006] Based on the planar phased array sub-array division model, Xu Ran’s 2015 study on several new systems and methods for improving radar imaging quality proposed a space-time two-dimensional random pattern design method for sub-array-level random initial phases. The space-time two-dimensional random pattern generated by the method has high correlation and poor low intercept performance

[0007] Some methods in the above research put forward extremely strict requirements on the frequency hopping bandwidth of the radar system; some methods have too high correlation of random patterns

In conclusion, there is no ideal low-correlation space-time two-dimensional random pattern design method in the prior art

Images