Research On The Optimization For Elliptical Planar Antenna Array

With the development and application of smart antenna,elliptical planar antenna array has gradually come into people's view.Since the birth of the antenna array,how to effectively improve the performance of the antenna array by adjusting the position or number of elements and other parameters has been a hot topic in related fields.Therefore,this paper studies the sparse distribution and sparse optimization of elliptical planar antenna array.Due to the irregular characteristics of elliptical array,the traditional optimization model is not suitable.It is urgent to propose a fast and effective optimization model.The main work is as followsFirst of all,because the accuracy of the position calculation of the plane array elements will affect the array factor,a method for accurately calculating the coordinates of the elliptical ring array elements is proposed,and then the elliptical array factor is derived.At the same time,in order to explore the influence of different eccentricity on the directional characteristics of elliptical ring array,the directional patterns of elliptical ring array with fixed semi major axis are drawn under different eccentricity.In order to solve the problem of computation difficulty in sparse distribution optimization of elliptic ring antenna array,a new minimum angle margin coding model is proposed instead of the traditional sparse distribution elliptic ring array model.The simulation results show that the new model has good applicability and effectiveness.It not only solves the problem of infeasible solution in the process of traditional model optimization,but also avoids the difficulty of ellipse arc length calculation.Secondly,in order to verify the effectiveness of the new model,the improved random fractal search algorithm combined with the new model is used to optimize the sparse distribution of elliptic ring array.In order to verify the optimization effect,two kinds of elliptical ring arrays with different spatial beam directions are studied.For the elliptic ring array with the same aperture and the same number of elements,the sparse distribution optimization is carried out under the conditions of limiting the width of the first zero point and not limiting the width of the first zero point respectively,and good results are obtained.Thirdly,in order to solve the problem that it is difficult to optimize the concentric elliptical ring array by using the traditional equal arc length model,this paper studies the concentric elliptical ring array,and gives a fixed number of elements mathematical model suitable for concentric elliptical ring array.At the same time,the equal arc length model which is difficult to calculate is replaced by the equal angle model,which can not only accurately limit the maximum number of elements on the ring,but also effectively speed up the calculation speed of the optimization algorithm.Simulation results show that the proposed model can achieve lower peak sidelobe level under the premise of equal number of array elements.Finally,a modified integer genetic algorithm is proposed to optimize the sparsity of rectangular grid arrays with different boundary shapes.Under the premise of ensuring the sparsity rate,a lower global peak sidelobe level is obtained,which verifies the effectiveness of the proposed algorithm.