Sub-reflector extensions for reduced noise temperature in low-side sub-reflector offset Gregorian systems

摘要

This paper describes a simple and low cost method to improve the noise performance of low-noise offset Gregorian antenna systems using a low-side sub-reflector mount configuration. A low-side mount has some logistical and maintenance advantages over the high-side counterpart, since the feed can be accessed without the need for a crane. A simple extension to the bottom of the sub-reflector is proposed which is shown to improve the antenna noise performance over that of the standard high-side mount configuration.