Scientists have successfully transmitted data at a rate of 26 terabits per second on a single laser beam - the equivalent of 700 DVDs in one second.
The Karlsruhe Institute of Technology (KIT) team sent the data over a distance of 50 km, and decoded it successfully using a new opto-electric decoding method. As no electronic processing methods are available for a data rate of 26 terabits per second, the team uses purely optical calculation in order to break down the high data rate to smaller bit rates that can then be processed electrically.
Professor Jürg Leuthold and his team applied orthogonal frequency division multiplexing (OFDM) for record data encoding, a process which has been used for many years in mobile communications.
"The challenge was to increase the process speed not only by a factor of 1000, but by a factor of nearly a million for data processing at 26 terabits per second," says Leuthold. "The decisive innovative idea was optical implementation of the mathematical routine."
Calculation in the optical range turned out to be not only extremely fast, but also highly energy-efficient, because energy is required for the laser and a few process steps only.
"Our result shows that physical limits are not yet exceeded even at extremely high data rates," says Leuthold.
“A few years ago, data rates of 26 terabits per second were deemed utopian even for systems with many lasers, and there would not have been any applications. With 26 terabits per second, it would have been possible to transmit up to 400 million telephone calls at the same time. Nobody needed this at that time. Today, the situation is different."