"The Fourier transform is a well-known mathematical trick that can in essence extract the different colours from an input beam, based solely on the times that the different parts of the beam arrive.<p>The team does this optically - rather than mathematically, which at these data rates would be impossible - by splitting the incoming beam into different paths that arrive at different times, recombining them on a detector."<p>This is cool, and makes sense.
>The trick is to use what is known as a "fast Fourier transform" to unpick more than 300 separate colours of light in a laser beam, each encoded with its own string of information.<p>No, the "trick" is decades of hard work and research in materials, electronics, photonics, signal processing and more.<p>Journalists like to believe you can sum up any scientific result in one sentence understandable by mortals. It turns out it's not the case.
Vint Cerf has stated that the theoretical capacity of fiber is 38THz of analog bandwidth:
<a href="http://www.nnsquad.org/archives/nnsquad/msg01402.html" rel="nofollow">http://www.nnsquad.org/archives/nnsquad/msg01402.html</a><p>I'd be interested to hear how close this record gets to the theoretical maximum, and where the intrinsic limit comes from.
Can someone "compare and contrast" this with existing CWDM and DWDM technologies, which also use different "colors" (think different frequencies, really) traveling over the same fiber?
They are using <i>LASERS</i> on fiber now? Sheesh - what will they think of next! Soon you'll tell me that RADIO WAVES can be used to transmit information!