LINE-OF-SIGHT COMMUNICATION

Seavey Engineering has developed a wide range of high performance angle diversity antennas for line-of-sight communication links which have certain extreme fading characteristics. In these links, the angle diversity antenna can dramatically improve the link reliability. 

The antennas consist of shrouded, high performance parabolic reflectors with RF absorber-lined aperture shields which have been equipped with an innovative feed system. The latter enables the antenna to have two vertically-splayed beams approximately one beamwidth apart. Diversity combiners are used on the two transmission paths to improve link fading statistics. 

Both dual and single polarized antennas are available for operation in all standard communications frequency bands. All antennas are equipped with standard tower mounts with elevation and azimuth vernier adjustments.In addition, waveguide combiners have been designed and delivered to yield sum and difference elevation patterns by combining upper and lower beam ports in a special hybrid network. 

Our angle diversity feeds consist of two closely spaced radiating apertures with special compensating devices to maximize isolation, control phase center position, and to optimize primary pattern shape. In typical reflectors, they result in two beams having crossover levels between 4 and 5.5 dB. Standard angle diversity feeds are dual linear polarized and have waveguide flanges. For optimum performance, they should be tailored to the F/D ratio of their mating reflector.

OTHER SPECIFICATIONS:
  • VSWR - 1.20, maximum

  • Isolation - 19 dB, minimum,

    • vertical-to-vertical ports
  • Pressurization - 2 psig, standard
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    Model 8800-800
    6 GHz Feed

    pg31bpg31c
    Model 8721-899
    10-foot 4 GHz Antenna
    pg31d
    Model 8722-899
    12-foot 6 GHz Antenna