A satellite multiple-beam antenna for high-rate data relays

This paper describes the concept and the development of key components of a novel multiple-beam antenna for satellite applications. The antenna is designed to be used in a transparent high-rate data relay system that links several low earth orbit (LEO) satellites to a single ground station via a satellite positioned on a geostationary orbit (GEO). The proposed antenna is based on the concept of an array-fed reflector. The antenna can track LEO satellites by switching between different subarrays of a bigger multifeed array using a reconfigurable switch matrix based on radio frequency micro-electromechanical system (RF MEMS) switches. The radiation characteristic of the antenna is further improved by combining digital beamforming with beam switching. In order to validate the proposed antenna concept and to show its suitability for space applications a demonstrator has been built. Measurements of the antenna's key components and of the demonstration system are given.