Design Aspects of a Compact Dual Band Feed Using Dielectric Rod Antennas With Multiple Element Monopulse Tracking

Monopulse tracking using multiple horns is an attractive and low-cost option for a ground station feed. In this paper, a compact design of this type of feed operating in dual band is discussed. This design uses dielectric rod elements as radiators. Four elements in 2 × 2 array configuration operate for downlink reception and tracking application. One single element with high gain at the center of the array operates for uplink using high power. This allows some design flexibility with respect to independence in configuring the two chains and also provides some inbuilt isolation between them. However, there are issues in this configuration with respect to the mutual coupling between the elements. These are addressed in detail and an optimum design with measured results of a tracking feed operating in 3.4 to 4.2 GHz for downlink and 6.3 to 6.8 GHz for uplink for an 11-m diameter dual shaped Cassegrain antenna is presented here.