Posts Tagged‘optics’

Fiber’s Future Looks Bright with Frequency Combs.

Fiber is the future of all communications, that’s a fact that any technologist will be able to tell you. Whilst copper is still the mainstay for the majority its lifetime is limited as optics are fast approaching the point where they’re feasible for everything. However even fiber has its limits, one that some feel we were going to hit sooner rather than later which could cause severe issues for the Internet’s future. However new research coming out of the University of California, San Diego paves the way for boosting our fiber network’s bandwidth significantly.

Fiber Optics

 

Today’s fiber networks are made up of long runs of fiber optic cable interspersed with things called repeaters or regenerators. Essentially these devices are responsible for boosting up the optical signal which becomes degraded as it travels down the fiber. The problem with these devices is that they’re expensive, add in latency and are power hungry devices, attributes that aren’t exactly desirable. These problems are born out of a physical limitation of fiber networks which puts an upper limit on the amount of power you can send down an optical cable. Past a certain point the more power you put down a fiber the more interference you generate meaning there’s only so much you can pump into a cable before you’re doing more harm than good. The new research however proposes a novel way to deal with this: interfere with the signal before it’s sent.

The problem with interference that’s generated by increasing the power of the signal is that it’s unpredictable meaning there’s really no good way to combat it. The researchers however figured out a way of conditioning the signal before it’s transmitted which allows the interference to become predictable. Then at the receiving end they’ve used what they’re calling “frequency combs” to reverse the interference on the other end, pulling a useful signal out of interference. In the lab tests they were able to send the signal over 12,000KM without the use of a repeater, an absolutely astonishing distance. Using such technology could drastically improve the efficiency of our current dark fiber networks which would go a long way to avoiding the bandwidth crunch.

It will be a little while off before this technology makes its way into widespread use as whilst it shows a lot of promise the application within the lab falls short of a practical implementation. Current optical fibers carry around 32 different signals whereas the system that the researchers developed can currently only handle 5. Ramping up the number of channels they can support is a non-trivial task but at least it’s engineering challenge and not a theoretical one.