New speed record for data rate with just a laser

Using just one laser, and a mathematical method called „Fourier transformations“, researchers have sent 26 terabits per second through a optic fiber. Researches separated 300 distinct colors from a laser beam, each carrying its own string of data.

Techniques for increasing data rates with light signals have improved significantly over the past years. One of them is OFDM(Orthogonal frequency division multiplexing), which uses several laser of different color, and each color codes its string of data. While receiving a signal like that, another set of laser oscillators is used to decode this information. The data rates while using such a method are limited only by the number of lasers used. One experiment showed a data rate of 100 terabits per second, but it is not commercially usable. Because the fore mentioned experiment used 370 distinct lasers, which are costly. Professor Freudeand his colleagues managed to reach comparable speeds using only one laser. At the basis of their method is a so called „frequency comb“, where light signals according to duration, give off different colors. The signals can later interfere in the fiber to create even more colors, to a maximum of 325 where each color carries its own data string. Original news can be found at BBC News web site.