Vehicular antennas for satellite communications

Antennas mounted at vehicles for satellite communications and direct broadcasting service are considered in the paper. The antennas have scanning beams with high gain as well as satellite tracking capabilities. Such antenna provides a wideband communication link via a satellite while a vehicle is in motion. Antennas are mounted on cars, buses, trains, ships, airplanes, etc. General requirements to vehicular antennas are discussed in the paper. Main concepts of vehicular tracking antenna design are described. They are: active phased array antenna with 2-D electrical beam steering, planar array with mechanical rotation in azimuth and 1-D electrical scanning in elevation, and a reflector antenna or a planar array on a 2-D positioner providing mechanical beam scanning. A survey on vehicular antennas developed worldwide in last decades is presented. Main trends of the antennas are discussed.