Research On Comprehensive Technology Of Vector Digital Array Polarization Pattern

With the development of vector sensor array and digital beamforming technique,the polarization domain is introduced into the pattern synthesis optimization and parameter estimation,which can effectively improve the communication capacity in communication system and the target detection,recognition and anti-interference capability in radar system.In order to optimize the polarized pattern by the vector array,a polarized pattern synthesis algorithm based on iterative alternating projection is proposed in this paper.The iterative algorithm is described as the sequential projection among several operators under the alternating projection theory and the least square method.The mainlobe shape of the co-polarized pattern is guaranteed and the sidelobe level and cross polarized level are controlled simultaneously.Accurate dynamic polarized pattern tracking is also realized by iterative correction of the desired pattern.The simulation and experiment results of linear vector array verified the effectiveness of the proposed algorithm in mainlobe shaping,sidelobe and cross-polarization control.Then,the algorithm is extended to plane vector array.Weighted least square method and diagonal loading regularization are respectively introduced,which can effectively improve the synthesis performance and optimization stability of the iterative algorithm.In order to solve the problem of adaptive anti-interference under polarized pattern maintenance of the vector array,adaptive algorithms based on direct multiple steering vectors constraints and subspace constraints are proposed respectively in this paper.The mainlobe maintenance constraint,sidelobe level constraint and cross-polarization constraint are introduced under the framework of linear constraint minimum variance(LCMV)optimization model.Furthermore,the optimization problem is transformed into a second-order cone programming problem and solved by convex optimization method.The mainlobe maintenance,sidelobe control,cross-polarization control and adaptive anti-interference performance of the two algorithms are verified on linear vector array.The simulation results show that the subspace constraint algorithm has higher stability in the sidelobe region and better adaptive anti-interference performance.