The Jet Propulsion Laboratory has developed a K/K/sub a/-band mobile vehicle antenna system that is much smaller and of higher gain than the L-band antennas. The new development is the ACTS Mobile Terminal (AMT) reflector antenna system, designed for use with NASA's Advanced Communications Technology Satellite (ACTS). It was scheduled to demonstrate mobile communications (voice, video, and data) from a mobile vehicle in southern California through the ACTS satellite soon after its launch in 1993. The reflector antenna system installs on the roof of the AMT vehicle. Initial tests show that the antenna and its satellite tracking system perform very well; it is small in size and rugged for operation in the mobile environment.<<ETX>>