Researchers have achieved record-breaking fiber-optic data transfer speeds of 402 terabits per second (Tbps) — roughly 1.6 million times faster than typical home broadband speeds.
The scientists at Aston University in the U.K. achieved these new speeds by tapping into all the wavelength bands used in commercially available fiber-optic cables. Only one or two bands are used in most fiber-optic broadband connections. They outlined their methods in a technical report published by Japan's National Institute of Information and Communications Technology (NICT).
The new record is 25% faster than the previous one set by the same team of scientists in March. In previous experiments, they achieved speeds of 301 Tbps by using four of the six wavelength bands in fiber-optic cables.
"This finding could help increase capacity on a single fiber so the world would have a higher performing system," Ian Phillips, a teaching fellow in electronics and computer engineering at Aston University, said in a statement. "The newly developed technology is expected to make a significant contribution to expand the communication capacity of the optical communication infrastructure as future data services rapidly increase demand."
To achieve the new record, the research team built the world's first optical transmission system that spanned all six wavelength bands used in fiber-optic communications, including O, E, S, C, L and U. These refer to different wavelength portions of infrared in the electromagnetic spectrum, falling between 1,260 and 1,675 nanometers (nm). Visible light, for reference, falls between 400 nm and 700 nm on the spectrum.
Most current commercial fiber-optic connections transmit data using the C-band and L-band portions, which range between 1,530 nm and 1,625 nm, because they are the most stable segments — meaning the least amount of data is lost through transmission. But increased network congestion means these bands will one day be saturated — meaning new bands will need to be used, the researchers noted in the report.
In the past, the S-band, adjacent to the C-band and occupying the 1,460 nm to 1,530 nm segment, has also been used in combination with the others in a "wavelength division multiplexing" (WDM) system to reach much higher speeds.
In the previous study, the scientists stabilized connections that used the E-band portion. Normally, data lost when transmitting in this region shoots up to extremely high levels — five times the data loss versus the C-band and L-band regions. This is because fiber-optic cables are susceptible to exposure to hydroxyl (OH) molecules in the ground that can enter the tubes and disrupt connections.
The new study went one step further and built new equipment that could also harness the O-band and U-band wavelengths. Specifically, the scientists built devices to amplify signals in the U-band portions. They also used off-the-shelf amplifiers to amplify O-band signals.
What’s more, they achieved these speeds on standard commercially available fiber-optic cables — meaning there would be no need to install specialized cables to tap into these speeds.
