Properties of a large scale multibeam antenna using a phased array fed reflector with radially aligned elements
Communication satellites achieve global communication coverage by using high-gain multibeam satellite antennas. These antennas fall into two types: direct radiating phased arrays for low Earth orbit (LEO) satellites and large reflector antennas fed by cluster feeds for geostationary orbit (GEO) satellites. This paper provides an analytical study of the phased array fed single reflector antenna that can cover wide regions like Asia by 127 beams based on our design techniques. To confirm the feasibility of the designed phased array fed reflector antenna a partial model of the array feed was manufactured and its electrical properties tested. Evaluation of the measured properties proves the feasibility of the phased array fed single reflector antenna as a large scale multibeam antenna.
The name of the present invention is "secondary radio wave propagation characteristic prediction system and method." A radio-wave propagation characteristic prediction assistance system includes a storage portion, the attribute information input and output portions. Attribute information storage section area and radio wave propagation characteristics of the reference region useful predictive information stored in association with each other. Attribute information input section inputs attribute information to predict the radio-wave propagation characteristic of the region. Output information stored in the storage portion of the search section to specify the region having the attribute information matching attribute input attribute information input section, and outputs the specified region associated with the reference information.