Study On Pattern Synthesis Algorithm Based On Dual Polarized Conformal Array

The conformal array antenna can be consistent with the shape of carrier surface,which can reduce the RCS.In addition,it can also expand the scanning range and improve the utilization of space,which has a broad application prospect.Each dual polarized conformal array antenna has two independent orthogonal polarized signal transceiver channels,which can control the co-polarized component and cross-polarized component of each element separately,and has stronger polarization information processing capability.Pattern synthesis is an important research topics of array antenna,which can achieve high gain,low side lobe,and even specific nulls pattern.Therefore,it has practical application significance.This dissertation mainly studies the pattern synthesis algorithm of dual polarized conformal arrays for the optimization of main lobe shape,side lobe level and cross polarization level.The main content of this dissertation is as follows:Firstly,in this dissertation the theory of planar arrays pattern is analyzed and three classical pattern synthesis methods of planar arrays are introduced.And then considering the inconsistency of element pattern and polarization feature,a dual polarized conformal array model is established.Then the aperture projection algorithm is used to conduct a simulation experiment based on a general arc array and dual polarized conformal array.Secondly,the pattern synthesis methods based on the adaptive theory and alternating projection theory are studied.And a WARP algorithm is introduced.Then,based on the alternating projection theory,an improved alternating projection algorithm is proposed,where the orthographic projection operator is improved to flexibly control the pattern outside the upper and lower bounds.In addition,an extra desired pattern is introduced to find an appropriate solution in the process of projecting the desired solution set to the feasible solution set.Virtual interferences are introduced to modify the solution iteratively based on the deviation between the obtained pattern and desired pattern.Simulation examples are presented to verify the validity of the proposed algorithm.Finally,the pattern synthesis method based on the convex optimization theory is studied.And two typical convex optimization problems for array pattern synthesis are introduced,including LP and SDP.Then an ICO pattern synthesis algorithm is proposed.The non-convex constraint about main lobe is rewritten as a convex constraint,which will bring error.And an auxiliary phase function is introduced to correct this error alternatively.Due to the deviation between auxiliary phase and real phase of pattern function,a method minimizing the peak of the synthesis error over observation angles is effectively applied to further improve the performance of the method.Numerical examples show good pattern synthesis ability and convergence performance of the ICO method.