Research On Anti-jamming Beamforming Algorithm For Largely Three-dimension Array Dimensionality Reduction

With the increasing complexity of the electromagnetic environment in modern warfare,the beamforming technology has been increasingly applied to the anti-interference field with electronic equipment.With the more complexity and diversity of the electromagnetic environment,the requirements of antenna array devices for adaptive beamforming algorithms will become higher.The large phased array has the advantages of long coverage distance,high resolution and many freedom,and it can also track multiple targets,so it has a very wide application prospect.However,the larger the antenna array elements number is,the higher the hardware requirements of large arrays is,so how to apply large array into practice has become an urgent problem to be solved.For the above problems,this thesis studies the anti-interference adaptive beamforming and the sum-difference tracking algorithm with dimensionality reduction of large 3D arrays.The research contents are as follows:First,for the signal model used and the 3D array,this thesis considers the "over-top phenomenon" during high elevation angle tracking in measurement and control communication.The derivation of the relevant formulas in the two angle mapping relationships used by the 3D array,and the application scope of these two angle mapping relationships and the conversion relationship between them.Secondly,in this thesis,due to the large number of array elements and the different antenna gains in the same target direction,it is not possible to use all array elements.Therefore,it is necessary to select the array elements.Selectting the array element according to whether the antenna unit can receive the signal,in first,and then uses the discrete quantum particle swarm algorithm to select the array element,which uses Master-slave ratio of adaptive beamforming patterns for the fitness function,the pattern formed by the antenna unit selected by this method have a better performance.After the array selection,the thesis proposed a method of reducing the array dimension which uses the storing pattern.Thirdly,this thesis analyzes the performance of adaptive beamforming using adaptive algorithms after reducing the dimensionality of 3D stereo arrays when the interference signals affect the target signals in the received data when there are interfering signals in the airspace.and adopts a algorithm which uses spatial smoothing to complete the antiinterference adaptive beamforming,so that the pattern forms a notch in the direction of the interference,and the main lobe is pointed accurately.Finally,this thesis shows a way of generating the sum-difference beams with large 3D array when the interference signals affect the target signals in the received data when there are interfering signals in the airspace in order to make the accuracy of sum-difference tracking higher,and shows the error of the sum-difference tracking is less than one tenth of beamwidth.