Dr. Xiang Liu's Team from Bell Laboratories Develop Noise Cancelling to Regenerate Fiber Optic Signals - The Shining Light at the End of the Tunnel

“At the receiver, if you superimpose the two waves, then all the distortions will magically cancel each other out, so you obtain the original signal back”

Researcher Dr. Xiang Liu and his team from Bell Laboratories speaking with the BBC on their use of Noise Cancelling Techniques to Regenerate Fiber Optic Signals

Telecoms Research is always exciting, even if is late news, so long as it is the latest development, Sometimes it’s development that is very simple, straightforward and Scientific.  The field of Photonics Research, a branch of Fiber Optics within Telecommunications, is wide open for innovation, especially as it relates to the End Termination Technology used to transmit and Receive Signals.

Even the University of the West Indies is getting into Photonics Research, having renamed the Faculty of Pure and Applied Sciences to the Faculty of Science and Technology as stated in my blog article entitled “UWI's Faculty of Pure and Applied Sciences is now Science and Technology as SPIE funds Optics Research - Welcome to the Punch at a multi-billion dollar Optics Revolution”.

Such as the recent development of Noise Cancellation to remove noise from Fiber Optic Signals as was recently tested by Researcher Dr. Xiang Liu and his team from Bell Laboratories as stated in the article “Tapping 'noise canceling' data signals for faster Internet”, published May 28, 2013 2:45 PM PDT by Nic Healey. CNET NEWS.

How their Noise Cancelling Technique works is very simple way to improve the signal Quality of a Fiber Optic Transmission and thereby extend the range without the need for frequent Repeaters. Their technique involves sending two (2) identical beams of light representing the Data being transmitted.

As the beams of light (actually in the IR Spectrum) Travel along the Fiber Optic Cable, it picks up Noise mainly due to imperfections in the Glass Fiber and refection at the points of termination. Remember, Fiber Optics uses Optical Frequencies and as such isn’t susceptible to EMI (Electro-Magnetic Interference).

By inverting one of the signals or beams of light at the Receiver and combining them in an Optical Summing Junction, the Noise and the Signal are both cancelled out. Then using Block Coding Techniques and the fact that they know what the signal is supposed to be, they can reconstruct the original Signal sans the Noise, thereby regenerating the Signal without need for further amplification.