Satellite Antenna Remoting

Analog fiberoptic links are available for signal transmission from 1 MHz to 40 GHz. There are many benefits to analog fiberoptic transmission, including the following.

  • Distance – Lower fiber loss and better noise performance compared to copper transmission allows for transmission to more remote locations and facilitates consolidation/simplification, and ease of implementing redundancy.
  • Cost – Lower size/weight and elimination of amplification required by coax/waveguide results in lower transmission costs for distances > 100 meters.
  • Bandwidth – Analog links up to 40 GHz are available.
  • EMI Immunity & Security – EMI, EMP, and ground loop “hum” are eliminated. Military TEMPEST protection is increased as there is no cable cross-talk between fibers, and fiber cannot be tapped without detection.
  • Fiber is lightweight and compact, 10% the weight of coax, 4% the weight of waveguide. Fiber is flexible and thin with armored kevlar versions available. Size/weight advantages accommodate redundancy, routing diversity, and mobility.
  • Lightning Protection is more straightforward and easier to implement with fiber.

Basic applications include the following.

  • Antenna Remoting – Antennas may be placed > 40 km from ground stations aiding in location logistics as well as security as active antenna elements radiate and may be targeted for attack.
  • Direct Microwave Transmission – Transmission from antenna site without down/up converting from/to L-band eliminates the need for nonlinear mixer elements and LO generation at the antenna site which results in degraded noise/distortion performance for longer links.
  • Antenna Diversity – Alternate antennas may be placed with 10s of kilometers of separation, ground station processing selects highest fidelity signal.
  • Secure Facility Penetration – RF and microwave signals penetrating secured/unsecured boundaries meet TEMPEST/HEMP requirements as a result of fiber EMI immunity.
  • LO Distribution – LO distribution through fiber accommodates improved phase stability compared to coaxial distribution. Microwave fiberoptic transmission provides direct LO transmission, eliminating nonlinear elements and phase-stable oscillators at each location. Fiber is less susceptible to phase variation due to temperature and other environmental variables.