Research On Sub-array-based Interference Suppression Adaptive And Difference Beam Angle Measurement Method

In the case of active interference,adaptive signal processing affects the weight vector of the sum and difference beams while suppressing the interference,causing distortion of the sum and difference patterns,and large deviations from the difference single-pulse angle measurement,resulting in sum and difference angular measurement performance is degraded or even invalid.In view of the above problems,this paper realizes the purpose of suppressing active interference and accurately obtaining the actual direction of the target on the basis of subarray.The research is carried out from three aspects: subarray beamforming,subarray based full adaptive sum and difference beam angle measurement,subarray based partial adaptation sum and difference beam angle measurement.Firstly,the principle of subarray beamforming is analyzed.The topology of subarray beamforming is different.The control effect and performance of the pattern are different:(1)The scanning is performed only by the phase shifter at the subarray level.Which analyzed the reasons for limiting the scan.(2)In order not to affect the scanning capability of the subarray,the phase shifter is used at the array level,and the time delay is used to scan at the subarray level.The influence of this condition on the instantaneous bandwidth is analyzed.(3)Considering the multibeam problem,the delay control portion of the subarray is replaced by connecting each subarray to one receiving channel for digital beamforming.(4)A beamforming method based on subarray for low sidelobe is introduced.(5)Finally,the overlapping subarray is introduced.The pattern has good performance deviating from the resonant frequency and can provide the window function like a filter.Secondly,the subarray received signal model of uniform linear array is established,and the conventional subarray and differential beam angle measuring methods under non-interference conditions are introduced.However,under the condition of active interference,the angle cannot be accurately measured.Then a method for sub-array adaptive difference beam weights of uniform linear array is proposed,which can obtain high angle measurement performance while suppressing interference,adaptive and difference beam single pulse ratio curve and ideal and differential angle.The curves are substantially coincident near the target direction.This method is then improved to make the robustness better.At the same time,the subarray partial adaptive and differential beam angle measurement methods for uniform linear array are studied,that is,subarray generalized sidelobe cancellation.The proposed method is compared with the method of subarray generalized sidelobe cancellation and difference beam angle measurement.And simulate it to verify its effectiveness.Since the method of measuring the angle of the uniform array is different from that of the line array,finally,the subarray received signal model is established for the uniform area array,and the static area array subarray and the differential beam angle measurement method under the condition of no interference are introduced.Then a method for subarray adaptive difference beam weights of uniform area array is proposed,which can resist both interference and angle measurement.However,this method needs to pay attention to the degree of freedom.If the number of interferences is large,the degree of freedom is not enough,and the angle cannot be accurately measured.At the same time,the subarray partial adaptive and differential beam angle measurement methods are also used to study the uniform area array.Finally,the simulation is carried out to verify its effectiveness.