Research On Beam Synthesis Technology Of Large-angle Scanning Conformal Array

At present,due to the rapid development of phased array antenna technology,people are no longer satisfied with the performance of planar array antenna,but put forward more stringent indicators for array antennas,such as smaller space occupation and wider scanning angle,lower profile height,etc.The conformal array antenna not only has the above advantages,but also fits well with the carrier,minimizing the impact on the aerodynamics of the carrier.However,the current high-performance conformal phased array antenna are mostly realized in the form of spherical arrays.Compared with other forms,spherical arrays have complex structures and are difficult to analyze when considering array element coupling,which brings great difficulties to conformal array beam synthesis.In addition,in view of the problem that the high cross-polarization level is difficult to suppress when the conformal array antenna is synthesizing the beam at a large angle,the optimization algorithm is currently used to optimize the conformal array unit globally,which makes the array synthesis process complicated and the overall efficiency is low.Based on the above problems,this thesis studies aspheric conformal phased array antenna that can realize large-angle beam scanning.The specific work is summarized as follows:1.A conformal phased array antenna with a truncated cone as the carrier is mainly studied,and the beam synthesis algorithm for realizing large-angle scanning and low cross-polarization is mainly studied.Firstly,the algorithm principle of applying the traditional aperture projection rule to the low cross-polarization conformal array is analyzed,and the formulas for calculating the feed amplitude and phase of each radiating element of the conformal array are obtained by the analytical method,and the conformal array is based on this.The array patterns under different angles,polarizations and effective radiation area angles are compared,and the effects of different parameters on the pattern results are analyzed.The pattern results show that the algorithm realizes the conformal array wide-angle beam scanning,and there is very low cross-polarization in the main beam during scanning,which is lower than-40 d B,which solves the polarization problem caused by the curvature of the conformal carrier.Compared with the traditional optimization algorithm,the algorithm proposed in this thesis has a faster calculation rate and greatly improves the beam synthesis efficiency.Finally,the full-wave simulation of the simulation software is used to verify the effectiveness of the algorithm.2.A special conformal array antenna,namely distributed conformal array antenna,is mainly studied.The working principle of the distributed array is briefly introduced,and the advantages and disadvantages of the distributed conformal array in radiation performance compared with the traditional planar array are analyzed and clarified.Starting from different antenna elements and array layouts,the distributed array antenna patterns are simulated and calculated.Firstly,the distributed linear array of ideal point source units is calculated,and the potential of large-angle beam scanning is verified by the pattern results.At the same time,the high side lobe problem caused by "distribution" is pointed out.Then,the distributed linear array of dipole is studied,and its array parameters are analyzed,which further proves that it has the performance of large-angle beam scanning.Then the simulation calculation and parameter analysis of the distributed planar array of ideal point source elements are carried out.The above research results prove the large-angle beam scanning performance of the distributed conformal phased array antenna,and provide guidance and reference for the subsequent distributed array related research and large-angle beam scanning research.