Summary
International Symposium on Antennas and Propagation
2008
Session Number:3C27
Session:
Number:3C27-4
Electromechanical Coupled Analysis of large broad band Reflector Antennas
Li Peng, Zheng Fei, Du Li-Gang, Song Li-Wei,
pp.-
Publication Date:2008/10/27
Online ISSN:2188-5079
Summary:
At present, in the electromechanical coupled analysis of reflector antennas, software for structure analysis is used firstly, such as ANSYS; and then the data from ANSYS is imported to software for electromagnetism analysis, such as FEKO; at last FEKO is used to calculate electromagnetism performance of the antenna. A FEM mesh is necessary in structure analysis. Another mesh is also requested by electromagnetism analysis; the side length is generally less than third of wavelength. The two meshes are independent, and do not match with each other. Especially for broad band antennas, different frequencies need different meshes; different meshes need independent electromagnetism analysis. So the efficiency of the electromechanical coupled analysis of broad band reflector antennas is low. Generally, there are two methods for the mismatching problems of structure mesh and electromagnetism mesh. The first one, A new surface of reflector is fitting from structure mesh, and electromagnetism mesh is obtained form the new surface[1,2]. In this way, new error will be bringer on in surface fitting. The second one, the data of structure mesh is imported to software of electromagnetism analysis directly. But A complex process include mesh refinement and uniform is necessary for structure mesh, because the mismatching of two meshes, especially for large antennas. For the problem of meshes in different frequencies, the mesh of high frequency could be obtained by thinning mesh of low frequency. The process is also very complex. For the problems above, electromechanical coupled model of reflector antennas has been modelled by GO method. An improved Gaussian formula has been used to calculate the model. A transformation matrix between structure mesh and Gauss points has been deducted. The Gauss points have been chose form structure mesh instead of complex mesh process. The number of the Gauss points is determined by antenna frequency, more points for higher frequency. Compared with FEKO software and tradition method, the method in this paper is accurate and effective, could be used in the electromechanical coupled analysis of large broad band reflector antennas. At last the method in this paper is used in a 40m reflect antenna, the result is accord with practice engineering.