Pillow Distortion Analysis for a Space Mesh Reflector Antenna

Abstract

Pillow distortion has become one significant limiting factor to the development of space mesh reflector antennas toward large-scale extension and high surface accuracy. However, the current state of the art about pillow distortion have great limitations in practical application, because they are mostly based on the assumptions that the stress applied on the mesh membrane is uniformly distributed and that the reflector is segmented into regular convex polygons by cable net. To improve the applicability and simplicity of the current state of the art, an alternative approach has been developed for the pillow disstortion analysis of space mesh reflector antennas without limiting assumptions in this paper. First of all, the triangular and quadrilateral cable-membrane elements are selected as conventional base units for space mesh reflector antennas. Second, equations and the calculation method were derived to investigate the pillow distortion of space mesh reflector antennas composed of triangular cable-membrane elements, based on the differential equations of membranes and cables, and then extended for that composed of other polygonal elements. To verify the validity and robustness of the proposed analytical method, some cable-membrane elements and a space mesh reflector antenna were taken as numerical examples. Eventually, the surface error distribution, root mean square error, and far-field electrical performance of an antenna influenced by the pillow distortion were conducted.