Research On Beam Forming And Interference Suppression Technology Based On Phased-array Radar

When detecting a target,it is often affected by the interference signal,which makes it impossible to accurately detect the effective information of the target.For different phased array models,different methods are usually used for beamforming and interference suppression,and when interference occurs in the main lobe of the beam,the better interference suppression capability is required.In this paper,based on the two typical array models of uniform linear array and uniform circular array,the research on beam formation and suppression of side-lobe and main-lobe interference is carried out.The main research contents are divided into the following parts.Firstly,the uniform linear array and uniform circular array model are introduced,and the basic principles of beamforming are introduced respectively.The particularity of uniform circular array beamforming is analyzed.After that,the basic principle of interference suppression technology is introduced.The interference suppression principle of two traditional methods,side lobe cancellation and Wiener filtering,is presented,and the side-lobe interference suppression effect under uniform linear array model is analyzed.Secondly,for the problem of uniform circular array side-lobe interference suppression,this paper introduces the reference function method,side lobe optimization and main lobe optimization static beamforming method.In order to obtain the low sidelobe level and form a notch at the interference position,this paper proposes an optimized main-lobe multi-constrained side-lobe interference suppression technique and an optimized side-lobe multi-constrained side-lobe interference suppression technique.And the virtual interference method to be used to enhances the suppression effect.In order to solve the problem of main-lobe interference,this paper introduces the preprocessing method of blocking matrix,and proposes a method based on high order blocking matrix preprocessing for the deficiency of blocking matrix.The construction method of high-order blocking matrix under linear array and circular array model is analyzed in detail,and its suppression effect on the complex envelope of main-lobe interference is analyzed.Then,based on the uniform linear array model,the effect of beamforming the signal preprocessed by the blocking matrix is analyzed.Finally,this paper uses the neural network method to continue to study the suppression of main-lobe interference.This paper introduces the BP neural network and RBF neural network models,and analyzes their respective core algorithms to construct a neural network structure that can suppress the main-lobe interference.Through simulation analysis,when the main-lobe interference DOA estimation is known,an ideal antenna pattern is formed,which can effectively form a notch at the main-lobe interference position,and ensure that the main beam is not deformed and the side-lobe level is lower.In this paper,the method of angle measurement using sum-difference beam amplitude ratio is analyzed,and the error of angle measurement is simulated.In this paper,the main lobe interference in different directions is considered,and relevant simulation is carried out to obtain a better suppression effect of the main-lobe interference.