Design of a Compact Multielement Monopulse Feed for Ground-Station Satellite Tracking Applications

This letter presents design and realization of a five-element compact dual-polarized feed for a 4.5 m Cassegrain ground-station reflector antenna. The realized monopulse feed is being used to track remote sensing satellites and receive imagery data in X -band frequencies (8-8.5 GHz). The multielement feed consists of one large-aperture corrugated horn acting as main element to extract the communication (sum port) signal and four side-launched circular waveguide elements around the central corrugated horn acting as tracking elements by extracting error signals in both azimuth and elevation. Various design issues of five-element communication/tracking feed assembly are presented along with simulation and measured results. The designed feed assembly satisfies the gain requirements of sum-and-difference pattern and serves as the most simple and compact design.