While high-speed wireless technologies like Wifi 6E and 5G dominate the news headlines, analog and optical cables are still the backbone of the Internet, and for good reason. Researchers in Japan have just established a new record for fiber optic data transmission with a technique compatible with existing cable infrastructure, which means that a real-world implementation is entirely possible and not just limited to an environment of laboratories.
Researchers at Japan’s National Institute of Information and Communication Technology (NICT) successfully sent data through a custom multi-core fiber optic cable at a rate of 1.02 bits per second over a distance of 51.7 km. That’s the equivalent of sending 127,500 GB of data every second, which researchers say is also enough for more than “10 million 8K broadcast channels per second.” As New Atlas points out, this is also 100,000 times faster than the promised new generation of high-speed gigabit connections that provide Internet to home users.
In December 2020, NICT made the first successful 1-petabit-per-second data transmission over a standard-diameter fiber-optic cable, and while a speed upgrade to 1.02-bit per second was only a a year and a half later it is certainly impressive. achievement, what makes this time so exciting is the technology used to break the record.
In 2020, NICT researchers sent the data over a single-core fiber-optic cable, but used a multimode technique where multiple signals were mixed during transmission. In total, 15 “modes” were sent for fiber together, and while the speed gains were impressive, multimode technology requires special hardware to decode signals and extract usable data, which requires development and the deployment of new integrated circuits to a whole set. Expensive network and upgrades make it harder to sell to Internet service providers despite massive bandwidth gains.
This time, the researchers eliminated the mixed and multimode signal approach and instead reduced the transmission to just four “modes” each sent to one of the four cores inside a custom fiber optic cable with a standard diameter. . Imagine a plastic straw with four thinner straws stuffed inside each with a different flavor of soda – a gross simplification of what the researchers created. But the multi-core cable was not the only innovation that made this record data transfer possible, it was also based on some highly technical optical amplification systems and signal modulation approaches, as described by NICT researchers:
In this experiment, by expanding the Raman amplification bandwidth to the full S-band and using custom tuli-doped fiber amplifiers (TDFA) for S-band and extended L-band erbium-doped erbium fiber (EDFA) amplifiers, we were able to use a record optical spectrum of 20 THz with a total of 801 x 25 GHz spaced wavelength channels, each with Dual-polarization QAM modulation-256 for high spectral density in all wavelength bands. good.
Most importantly, this second breakthrough is based on hardware and techniques that are fully compatible with conventional transceiver hardware that already exists nationwide. New fiber optic cabling will need to be installed, but as researchers limited the size of their multi-core cable to standard dimensions, it would be fully compatible with existing infrastructure, greatly reducing upgrade costs. As 5G spreads further, and with 6G just around the corner, the country’s demand for data will continue to rise by leaps and bounds, but an innovation like this promises to give Internet providers a sizeable advantage for at least a few years. .