A satellite-tracking K- and Ka-band mobile vehicleantenna system

This paper describes the development of the K- and K_a-band, satellite-tracking mobile-vehicular antenna system for NASA's ACTS Mobile Terminal (AMT) project. ACTS is NASA's Advanced Communications Technology Satellite, which will be launched into its geostationary orbit in September 1993. The AMT task will make the first experimental use of the satellite soon after the satellite is operational, to demonstrate mobile communications via the satellite from a van on the road. The AMT antenna system consists of a mechanically steered small reflector antenna that uses a shared aperture for both frequency bands and fits under a radome of 23 cm diameter and 10 cm height, and an antenna controller that tracks the satellite as the vehicle moves about. The RF and mechanical characteristics of the antenna and the antenna tracking control system are discussed. Laboratory measurements of the antenna performance are presented