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Beam scanning offset cassegrain reflector antennas by subreflector movement
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Lapean Jr., James W. Stutzman, Warren L. |
| Copyright Year | 1994 |
| Description | In 1987 a NASA panel recommended the creation of the Mission to Planet Earth. This mission was intended to apply to remote sensing experience of the space community to earth remote sensing to enhance the understanding of the climatological processes of our planet and to determine if, and to what extent, the hydrological cycle of Earth is being affected by human activity. One of the systems required for the mission was a wide scanning, high gain reflector antenna system for use in radiometric remote sensing from geostationary orbit. This work describes research conducted at Virginia Tech into techniques for beam scanning offset Cassegrain reflector antennas by subreflector translation and rotation. Background material relevant to beam scanning antenna systems and offset Cassegrain reflector antenna system is presented. A test case is developed based on the background material. The test case is beam scanned using two geometrical optics methods of determining the optimum subreflector position for the desired scanned beam direction. Physical optics far-field results are given for the beam scanned systems. The test case system is found to be capable of beam scanning over a range of 35 half-power beamwidths while maintaining a 90 percent beam efficiency or 50 half-power beamwidths while maintaining less than l dB of gain loss during scanning. |
| File Size | 4792024 |
| Page Count | 210 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19940024333 |
| Archival Resource Key | ark:/13960/t03z3621c |
| Language | English |
| Publisher Date | 1994-03-01 |
| Access Restriction | Open |
| Subject Keyword | Launch Vehicles And Space Vehicles Radiometers Remote Sensors Mission To Planet Earth Scanners Geometrical Optics Reflector Antennas Rotation Remote Sensing Antenna Design Physical Optics Cassegrain Antennas Subreflectors Geosynchronous Orbits Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Technical Report |
