Numerical study of the effect of the struts in a reflector antenna system by usin the parallelized FDTD-based solver GEMS

Large, axially-symmetric reflector antenna systems are widely used in various applications, such as radio astronomy, deep-space links and satellite communications. In most of the reflector geometries utilized in these applications, the antenna aperture is partially obstructed by the feed as well as by the supporting strut structures. The blockage decreases the overall antenna gain, increases the side-lobe and cross-polarization levels, and this, in turn, increases the antenna noise temperature. It is desirable to be able to estimate the effects of the struts on the performance of the reflector antenna, so that the design could be modified to mitigate the problem, at least partially.The parallelized Finite-Difference Time-Domain (FDTD) software package GEMS, which is enabled with the Message Passing Interface Library, has been adopted to carry out the simulations for the reflector antenna system, since it is capable of handling electrically large and complex systems with very high accuracy and numerical efficiency, and it exhibits excellent scaling properties on large computer clusters.