Optical Zonu has successfully deployed fiber as a replacement for waveguide to transport Ku-Band CDL communications payloads between radomes mounted high above the decks of ships and equipment rooms situated within the hulls of ships. Antenna Remoting over fiber enables greater flexibility to locate an antenna away from a radio head. Waveguide (and coaxial cable) have significant RF losses and are cumbersome to install and maintain. In existing installations, legacy waveguide is actually used as a conduit for the optical fiber.
Fiber benefits over waveguide include the following
- Fiber has much better long-term performance and the overall lifetime cost to install and maintain fiber is much less than waveguide.
- Waveguide is rigid and RF performance is highly susceptible to any mechanical stress (shock, vibration). Any ding during assembly, installation, or maintenance will affect waveguide RF performance.
- Fiber is flexible, easy to install, and has a bend radius less than 1 inch. Standard fiber diameter is 3 mm. Waveguide is not flexible and standard cross section for Ku-Band transport is 8 x 16 mm.
- Waveguide is fragile and must be kept extremely clean and dry. The slightest amount of moisture or the smallest contamination of dirt or salt will degrade the transmission of waveforms and resulting RF performance. In order to keep moisture out, waveguide is usually filled with dried air or purified nitrogen. Any corrosion or oxidation of the waveguide inner metal surface will degrade performance. On very high-powered waveguides, the air within may be pressurized and/or recirculated, or a Freon-like gas must be used to cool the waveguide.
- Installation cost of waveguide is higher and requires a higher level of expertise onsite to install and maintain. Interfaces at waveguide flanges must be precisely matched to prevent waveform degradation.
The Common Data Link (CDL) is a secure communications protocol for transporting signals intelligence and imagery. In many cases, it is not feasible to upconvert/downconvert the Ku-band signals at an antenna. Optical Zonu’s CDL fiberoptic transport links meet the requirement of transporting Ku-Band RF signals over much longer distances than can be supported by waveguide. Optical Zonu CDL fiberoptic links meet and exceed all of the following CDL requirements.
- 14.4 – 14.83 GHz D/L and 15.15 – 15.35 GHz U/L
- Low loss transport, 0.7 dB/km over a single fiber
- Support all CDL compliant waveforms
- Symmetric/asymmetric data rates
- 10/100/1000 Base-T Ethernet datalink
- Audio/video transport