Satellite technology is developing fast, and the applications for satellite technology are increasing all the time. Not only can satellites be used for radio communications, but they are also used for astronomy, weather forecasting, broadcasting, mapping and many more applications.
With the variety of satellite frequency bands that can be used, designations have been developed so that they can be referred to easily.
L-Band: 1-2 GHz
S-Band: 2-4 GHz
C-Band: 4-8 GHz
X-Band: 8-12 GHz
Ku-Band: 12-18 GHz
K-Band: 18-27 GHz
Ka-Band: 27-40 GHz
V-Band: 40-75 GHz
The higher frequency bands typically give access to wider bandwidths, but are also more susceptible to signal degradation due to ‘rain fade’ over air communications. All signals for the satellite bands shown above are degraded when routed through coaxial cables or wavguides due to high insertions losses of these high frequency signal conductors, except when the signals are transported through Fiberoptic cables and RFoF technology.
The Radio Over fiber or (RFOF) ultimately is the best solution for transporting all the Satellite bands specially for higher frequency bands such as S, X, Ku and Ka, bands where Coaxial cable suffers from considerable signal loss, Fiber optic links are almost loss-less, so engineers can plan and install links of 10Km or longer, with very little signal loss. Fiber is lighter weight and easier to physically route.
Coaxial cable is rather heavy and bulky. OZC S-Band Transceivers & L-Band Transceivers (both a transmitter and a receiver housed in the same enclosure as a single unit RF over Fiber), as well as offering in the C Band, X-Band, Ku, K, & Ka bands for higher frequency RF Via Fiber (or RF over Optical) individual analog Fiber optics Transmitters or analog Fiber optics Receivers all manifest RF Via fiber as the best solution from loss reliability and range considerations.
Fiber simply provides more bandwidth than cable and with more bandwidth, fiber optics more easily allow Transport of all types and signals required for Satellite communications applications. Finally, fiber optics are typically upgraded through advancements to the electronic technology converting Radio frequencies to light and Vice Versa and, not by replacing the fiber as it’s the case in coaxial infostructures. For this reason, fiber is considered “futureproof” – the technology can easily evolve.
Although optical fibers are hair-thin, they have the capacity for greater bandwidth than traditional coaxial cables. Fiber technology has transformed the way Satellite signals are transported, from few meters to distances of 100km or more.
Optical Zonu Radio over fiber (Analog over fiber) currently supports all the Satellite Bands indicated above except V band (target release date Q2/2020) and W band for short reach or long-haul applications.
Optical Zonu offers a broad range of products for Satellite communication over fiber in a variety of form factors supporting various Satcom applications such as:
• Phased Array Radar, as steerable communication antennas require hundreds of RFoF feeds to/from radiating elements.
• Antenna Remoting, typically used to provide safety of the Users from Radiation and enemy attacks.
• Direct Microwave Transmission X, Ku, K, Ka and more, which is Transmission of High frequency signals from antenna site without down/up converting to L-band or other IF bands.
• Electronic Countermeasures (ECM) can be either jamming or deception. The wideband and high frequency characteristics of analog fiber optic links provide the desired medium and flexible configurations needed for deployment in fixed, tactical, airborne and shipboard environment
• Antenna Diversity – to provide redundancy, operation in higher Modulation code Index and higher Carrier Noise environment
• Secure Facility Penetration – providing transport of highly sensitive RF Signals to and From high security environments and additionally benefiting from fiber EMI immunity.
• LO Distribution – Microwave fiberoptic transmission provides direct LO transmission, eliminating nonlinear elements and phase-stable oscillators at each location.
To Transport Satellite signals over Fiber one parameter is very critical for RFoF Transporting such signals, is HIGH Spurious Free Dynamic Range (SFDR). To achieve High SFDR a low Noise figure and high 1dB compression point of the fiber optic link is a must, something Optical Zonu can offer in variety of packages, indoor and outdoor.
Spurious free dynamic range (SFDR) is defined as the ratio of the maximum signal without creating detectable distortion to the minimum signal that is just above the system noise floor.
RFoF Link Design Guideline.pdf
Other significant advantages of transporting Satellite signals over fiber is that the entire RF spectrum of a single Satellite band or Multiplexed many Bands (RF signals) into one common signal can be multiplexed further optically to increase capacity 48-fold into a singles strand of fiber utilizing Dense Wavelength Division Multiplexing (DWDM) technology.