RF Optics

The term RF Optics can be a confusing concept – hence we will try to clarify how, and when, it is actually being used within modern communication infrastructure. Both RF – which stands for Radio Frequency – and light are a form of radiation that differ only in the wavelength. RF cover bands from HF (starting at 3MHz) up to mm waves (ending at 300GHz) – see here for a table that divides the different band designators). Optical wave propagation is usually referred to electromagnetic (EM) radiation in the 500nm to 1650nm range (180,000 – 600,000GHz). There is a vast order of magnitude difference between the two widely electromagnetic waves. Both propagate at the speed of light, but they suffer different attenuation in different media. Light can be easily focused and coupled into a fiber optic cable that typically has losses of 0.2-0.4 dB/km. For more details about the RF losses on waveguide/coax transport please see our Coax over Fiber post

Due to the vast frequency difference it is possible to modulate light signal with RF signal(s) (similar to the way that audio is modulating RF waves for our radios to work). The light can be propagating in free space (refered to as “free-space optics”) or through a fiber optic link. RF Optics is synonym to RF over Fiber.  The RF Over Fiber branch of RF Optics is widely utilized to propagate RF signals over medium to long distances where the cable/coax/waveguide attenuation (loss) is too high to be successfully utilized.

Examples abound:

  • Satellite communication
  • GPS propagation
  • CDL
  • Wireless Cell coverage/BaseStation extension and Transport
  • and many others

Please visit our website to learn more at www.opticalzonu.com