Scientists send data at 1,125Tbit/s

Scientists have managed to transfer data at 1,125Tbit/s, 12.5 percent faster than demonstrated so far. This was done by using a ‘super channel’ with a total of fifteen channels to transport the data.

The idea of ​​these superchannels is not new, but it is the first time that data has been successfully sent at more than 1Tbit/s to a single receiver, scientists at UCL University in London claim in a paper published today. in Scientific Reports. The researchers make the comparison that such speeds make it possible to download all episodes of Game of Thrones in a second.

The experiment took the maximum signal-to-noise ratio, or snr, of 24dB from a state-of-the-art transceiver as a basis. “The key to maximizing the number of bits that can be reliably sent over a fiber is to simultaneously optimize the modulation format and code rate, based on the receiver’s SNR,” the researchers write. The code rate is the part of the data stream that is actually usable.

The team used fifteen different carriers to transfer data. Each channel carried a signal of a different wavelength, which was modulated using the 256QAM format. The channels were bundled into a super channel for a single receiver. Adopting higher QAM formats would not result in faster speeds due to the current 24dB snr limit, but if transceiver subsystems improve and better signal-to-noise ratios come within reach, this could be an option.

The research is intended to see whether creating superchannels is a good way to increase the speed of connections in the future. That is by no means certain: in this study, the transmitter was connected directly to the receiver. The scientists now want to test the influence on the system of disturbance of the optical signal, which occurs during transmission at long distances.