Title :
Cassegrain Antenna With Hybrid Beam Steering Scheme for Mobile Satellite Communications
Author :
Jung, Young-Bae ; Shishlov, Alexander V. ; Park, Seong-Ook
fDate :
5/1/2009 12:00:00 AM
Abstract :
A hybrid antenna (HA) with a modified beam steering method is proposed. This antenna has a Cassegrain structure composed of two reflectors and a feeder. The parabolic-shaped main reflector is designed for high gain, while the subreflector is rotational and flat. The feeder is a phased array with arbitrary shaped aperture and 20 element antennas. The HA is capable of two-dimensional beam steering by means of two operations: rotation of the subreflector and phase control of the feed array. The subreflector is small in size and weight, so it can provide rapid beam scanning. Designed to be loaded in vehicles, the HA and can communicate with satellites on the move by tracking the beam control of the feed array. A prototype of the HA is fabricated with aluminum using a machining center operated by computerized numerical control. The prototype is operated at Ka-band for TX and K-band for RX with gains of 47 dBi and 44.4 dBi, respectively, at a steering angle of 0 deg. The two-dimensional beam steering within plusmn2deg with respect to 45deg elevation is realized by the subreflector and feed array. All radiation patterns in the beam steering zone meet ITU-R s.465-5 regulations.
Keywords :
aperture antennas; beam steering; mobile satellite communication; reflector antenna feeds; satellite antennas; Cassegrain antenna; arbitrary shaped aperture antennas; beam control; computerized numerical control; feeder; hybrid antenna; hybrid beam steering scheme; machining center; mobile satellite communications; parabolic-shaped main reflector; phased array; subreflector; Antenna arrays; Antenna feeds; Apertures; Beam steering; Mobile antennas; Phased arrays; Prototypes; Reflector antennas; Satellite antennas; Satellite communication; Hybrid; mobile antenna; reflector; satellite communications;
Journal_Title :
Antennas and Propagation, IEEE Transactions on
DOI :
10.1109/TAP.2009.2016706