Accession Number : ADA112209

Title :   Ehf Multiple Beam Antennas.

Descriptive Note : Final rept. Nov 79-Oct 81,

Corporate Author : NAVAL OCEAN SYSTEMS CENTER SAN DIEGO CA

Personal Author(s) : Major,R W ; Devan,J M

PDF Url : ADA112209

Report Date : 21 Sep 1981

Pagination or Media Count : 57

Abstract : The objective of this task was to design, build, and test a multiple-beam, ehf, satellite antenna system for reception of shipboard SATCOM transmissions. The system was to provide full earth coverage with multiple spot beams. The spot beams serve to enhance gain to signals in a given sector while decreasing gain to jammers not in that sector. The chosen design was a system employing a waveguide lens and 37 feed horns. Computer simulation of a lens design indicated that the system could provide 37 simultaneous beams with a minimum gain of 27 dB over the earth, at least 40.0% efficiency, and sidelobes 20 dB down. A waveguide lens, feed horns, a mixer, and an IF amplifier were fabricated or purchased. The system provided a minimum gain of 27.4 dB, the largest sidelobe was 19.8 dB down, and efficiency ranged from 41.6 to 43.5%. (author)

Descriptors :   *Antijamming, *Satellite antennas, *Multiple beam antennas, *Satellite communications, Antenna feeds, Multiple beams(Radiation), Computerized simulation, Extremely high frequency, Area coverage, Earth(Planet), Waveguides, Lenses, Gain, Sidelobes, Antennas, Signals, Jamming

Subject Categories : Electrical and Electronic Equipment
      Countermeasures
      Unmanned Spacecraft

Distribution Statement : APPROVED FOR PUBLIC RELEASE