London, March 20 : German researchers have achieved a breakthrough in making the first wireless video transmission in the terahertz range, potentially 1000 times faster than the existing wireless technologies.
Christian Jastrow of the Terahertz Communications Lab in Braunschweig says that, though the link spanned just 22 meters, the transmission marks a significant advance towards using much faster chunks of wireless spectrum, by harnessing radio waves oscillating a trillion times per second.
The present-day wireless technologies like WiFi and third generation (3G) mobile networks operate in the ranges of gigahertz and megahertz respectively.
Jastrow says that using terahertz bandwidth, ranging from 300GHz to 3 terahertz (THz), may open up new frequencies for communication.
"If you want to do very high rates of communication, you have to use terahertz frequencies," New Scientist magazine quoted him as saying.
Jastrow and his colleagues combined a host of commercially available frequency multipliers to make a 10 GHz microwave generator, with the help of which they could produce the lowest frequency of terahertz, i.e. a 300 GHz wave.
The researchers used the system to transmit television show 'Futurama'.
Jastrow revealed that his team used a specially designed high frequency transmitter and polyethylene lens to focus the waves into a relatively low-power beam, which transmitted the video signal of up to 22 meters before the earth's atmosphere absorbed it.
He envisions that terahertz transmissions may make for improved video conferencing and faster dowloading of film and heavy files, which currently takes several minutes to complete.
University of Utah expert Ajay Nahata hailed Jastrow's work as "very impressive", but insisted that the terahertz range could be used up to a certain limit.
"They did a nice job of showing something people have been trying to get to, and they did it using commercially available components. But they can't scale it up to 1 or more terahertz," he said.
Nahata revealed that he and his colleagues were working experimenting with ultra-fast lasers as terahertz generators to get around such limits.
"People are going to have to come up with other ways of doing this if they want to go to much higher frequencies. Whenever people think they have gone as
fast as is necessary, that very quickly gets used up and people want more," he said.
A report on this research has been published in the journal Electronic Letters.