RFoF Distribution Frequency Range on SATCOM at a Glance
RF over fibre (RFoF) refers to a technology where radio frequency analog signals modulate a light source (laser) and are transmitted over an optical fibre link. With RFoF technology, large bandwidths at high frequencies can be distributed over long distances with very low losses and with minimum impact on signal integrity. The large bandwidth spectrum used in common satellite communication generally refers to C, Ka and Ku bands. The signals from satellites are received at the antenna at frequencies above 6GHz. Then typically after the LNAs, these received signals are down converted to an intermediate frequency known as L band (850-2450MHz). DEV Systemtechnik, is one of the pioneers of SATCOM industry with field-proven L Band systems not only for RFoF solutions but also RF Matrices, Redundancy Switches and RF Distribution Equipment. From today’s perspective, it is no secret that the common use of L Band on the ground segment is a heritage from the times where the coaxial distribution was the only option to transmit RF signals in a wired network. Of course, when talking about coaxial distribution, the intermediate frequency should be as low as possible due to high attention occurred on higher frequencies. But when we look at this at today’s perspective where almost all the infrastructure of large teleports are already based on fibre, it might be a good time to talk about carrying higher frequency on fibre links.
Wideband RF Over Fibre Systems up to 18GHz
Utilising advanced communications technology, fibre can efficiently transport analog signal over great distances in their native bands without down converting the high frequencies. Transmission from antenna site without down/up converting from/to L-Band prevents potential performance signal degradation due to any distortion caused by local oscillators and mixer elements. This also enhances the overall system reliability as there are fewer components in the signal chain.
This direct microwave transmission enables and simplifies applications such as antenna diversity over long distances, separation and centralisation of down conversion and demodulation and cascaded modulator topology. As an example, for the uplink chain, this new structure can enable modulators and local oscillator to be placed in different locations for antenna remoting applications.
When talking about direct microwave transmission over fibre, the challenge will be to provide high dynamic range and low noise RFoF systems. With DEV’s expertise on up to 18GHz RF distribution systems and thanks to company’s flag ship RFoF system Optribution’s flexibility in design, DEV is ready to offer > 6GHz fibre links (Optical Transmitters and Receivers) of the shelf! It is either the direct transmission of a C-Band antenna at 6 GHz or a Ku-band antenna at 18GHz, DEV has the high performance, manageable and fully modular RFoF system for global satellite industry.
A Quick Look to DEV’s Best Selling RFoF Platform Optribution
Optribution allows complex switching, redundant configurations and long-distance signal transport up to 500 km for with both indoor and outdoor options. The Optribution product line features a wide selection of diverse fibre transmission and signal distribution modules for switching, splitting, CWDM/DWDM, redundancy routing and much more! The Optribution platform and compatible DEV Systems are deployed in more than 100 countries for high performance RF distribution and is trusted by Teleport operators for more than two decades.
- 20 Slots for optical Transmitter or Receiver Modules for up to 40 Signals.
- 1+1 Redundancy | N+1 Redundancy (n=4, 8, 12, or 16) for RX/TX.
- CWDM up to 8-16 Channels | DWDM up to 49 Channels.
- MUX/DEMUX and Optical Splitters • EDFA and Delay Line Selection.
- Ethernet to Optical Converter Option.
- Power Supply Redundancy.
- DEV Web Interface | SNMP Support.
- 7 Years Warranty.
On top of the endless possibilities and benefits of transmitting non-down converted signals, with the new frequency allocation plans boosted by global roll out of 5G, the need for a higher spectrum on the ground segment is demanding more than ever. To follow and even lead these deployments, DEV is fully ready to move forward with its partners and customers. Wideband up to 18GHz RFoF system is built on the proven DEV Optribution platform and is fully compatible with existing Optribution chassis.