Research On Adaptive Beamforming Technology Of Missile-borne Array Radar

In recent years,with the continuous development of electronic countermeasure technology,the electromagnetic interference environment has become more and more complicated and diversified,which brings new opportunities and challenges for the development of radar seekers.Array radar seeker has become a hot research direction of the current precision guided radar seeker with its flexible beam control,strong anti-interference ability and adaptability.When the missile-borne array radar faces side-lobe interference,the sub-array adaptive beamforming technique is generally used to suppress the interference,but this technique often causes distortion of the differential beam pattern,which leads to the angular measurement performance of the missile-borne array radar.Declining;when facing the main lobe interference,the sub-array four-channel main lobe interference suppression technique can well eliminate the main lobe interference,but the technique is only applicable to the rectangular array model,which is applied to the missile array radar.In the case of non-rectangular matrices,the accuracy of the angle measurement is degraded because the adaptive single-pulse ratio is inconsistent with the static single-pulse ratio.In view of the above problems,this paper develops an adaptive beamforming technique based on missile-borne array radar.Firstly,the digital beamforming technique and the difference beam angle measurement technology are introduced.Then,the sub-array beamforming technology is introduced.According to the commonly used sub-array division rules,two non-rectangular array models of missile-borne array radar are proposed.Different sub-array division schemes,and the performance of the above two different division modes are analyzed and compared by simulation.Secondly,when the missile-borne array radar faces sidelobe interference,the sub-array adaptive single-pulse technique will cause the angle measurement performance to decrease.The sub-array-level constrained adaptive single-pulse technique is adopted.The pulse ratio ensures that the adaptive single pulse ratio is the same as the static single pulse ratio within the constraint range,so that the original angle measurement accuracy can be maintained,and the effectiveness of the technique is verified by simulation analysis.Finally,based on the traditional four-channel main-lobe interference suppression technique,a single-pulse angle measurement method for the missile-borne array radar facing main lobe interference is proposed.In this method,in order to obtain a narrow main lobe width,the beam is directly generated from all sub-array data;in addition,in order to fully utilize the array aperture of the array antenna while satisfying the requirements of each sub-array for the center symmetry of the array,Different selection matrices select the sub-array data to form a difference beam.Then,the linear compensation technique is used to linearly adjust the beam output and the single-pulse lookup table.Finally,the main lobe interference suppression and the target angle measurement are performed.The method can realize the suppression of the main lobe interference and the accurate estimation of the target angle by the missile-borne array radar in the main lobe interference environment.At the end of the thesis,relevant simulation experiments are carried out to verify the correctness of the method.