Research On Tolerance Analysis And Design Methods For Antenna Array Radiation Performance

Antenna array is a very important electromagnetic equipment in modern defense and commercial communication.It is developing rapidly towards multi frequency bands,high anti-interference ability,high reliability,integrability and low system cost.There is a complex nonlinear coupling relationship between array structure parameters or feed parameters and electromagnetic performance.Parameter errors may result in severe degradation of radiation performance of antenna arrays.How to evaluate the worst arrays performance affected by errors and control parameters error in practical applications becomes an urgent problem for robust array design.On the background of array position error,the prediction methods of array radiation performance tolerance bound and the corresponding tolerance design methods are studied deeply.The specific works are as follows:1.A three-dimensional interval position error model of planar antenna array is established,and the performance interval determination method of far-field radiation pattern based on non-probabilistic interval analysis and first-order Taylor Linear approximation is studied for small position errors.The response interval of pattern function are given analytically,and the tolerance of gain loss and peak side-lobe level to error are analyzed.Both simulation cases and the measured results of the 16-element patch antenna array prove that the proposed method the effectiveness and reliability of two methods for evaluating the impact of smaller interval position errors.2.A novel method is studied to determine the array pattern performance interval based on quadratic relaxation programming,which effectively solves the problems of potential response interval expansion and low reliability existing in the interval analysis method and the first-order Taylor linear approximation method.The method introduces the second-order partial derivative information of the pattern function to the error variables,and a mixed convex and non-convex quadratic optimization problem subject to box constraints is firstly formulated.Then,a convex semidefinite relaxation version of the non-convex subproblem is designed.Finally,the convex optimization based on the interior point algorithm is used to solve the proposed problem.The complexity of the proposed method is proved to be at most polynomial in the variable dimensions.Therefore,it has high solving efficiency.The simulations include a sparse antenna array pattern experiment,and fully verifies that the proposed method can not only ensure the complete reliability and prediction accuracy for the pattern tolerance bounds,but also provide a relatively accurate and reliable peak sidelobe level performance interval when dealing with a larger degree of position interval error.3.A novel design method of non-uniform position tolerance of antenna array based on quadratic relaxation programming is studied,and effectively improves the traditional Monte Carlo tolerance design method constrained by random experimental processes and statistical models.This method decouples the power pattern function into a function of position error variable and its theoretical value.A quadratic convex programming optimization problem for array position tolerance design is derived based on the synthesis problem of optimal focusing beam pattern.The simulations verify that the proposed method achieves tight tolerance design while meeting the expected radiation performance index loss,which is conducive to the reasonable installation and deployment of antenna units in engineering.It is an efficient and practical method.The research work in this paper can provide theoretical reference for robust array design and array error evaluation.