New Record Fibre Optic Speed of 1.02Pbps Hit Over 51.7km

A team of network researchers from the National Institute of Information and Communications Technology (NICT) in Japan has done it again after they achieved the “world’s first” successful data transmission of 1.02 Petabits per second (Pbs) in a standard cladding diameter (0.125 mm) multi-core fibre cable over a distance of 51.7km.

The eagle-eyed among you will promptly recall that NICT, which has a long-running history of setting new transmission records in the field of fibre optic broadband and data communications, previously hit a speed of 1.01Pbps in December 2020 (here). But there are a number of key differences between that test and the new one.

The December 2020 result used a single-core cable with 15 fibre modes (multi-modes) – via the C + L wavelength bands – over a distance of just 23km. The setup for that harnessed 10THz of transmission bandwidth and a data-rate / spatial channel of 67.3Tbps (Terabits per second). But this required complex MIMO (Multiple-input-multiple-output) digital signal processing to unscramble the signals, which adds to the cost and development required.

By comparison, the new record was achieved without any MIMO (i.e. conventional transceiver hardware can be used) and harnessing a multi-core (4 core) cable (MCF) with just a single fibre mode – via the S + C + L bands (total of 801 wavelengths and 256QAM) – over a longer distance of 51.7km. The setup also harnessed 20THz of transmission bandwidth and a data-rate / spatial channel of 255Tbps (255Tbps x 4 cores = 1.02Pbps). A similar setup was used in June 2021 to transmit data over 3001km, albeit at a speed of 0.319Pbps.

The cable being tested is, according to the research team, “thought to be the most likely of the new advanced optical fibres for early commercial adoption“, which makes this demonstration of their record-breaking capabilities all the more important.

Summary of Achievement

NICT constructed the transmission system using 4-core MCF with standard 0.125 mm cladding diameter, WDM technology and mixed optical amplification systems. The system allowed transmission of 1.02 petabit per second over 51.7 km. Previously, 610 terabit per second was achieved in a similar fiber but only using part of the S-band.

In this experiment, by broadening the Raman amplification bandwidth to the full S-band and using customized thulium-doped fiber amplifiers (TDFAs) for S-band and extended L-band erbium-doped fiber amplifiers (EDFAs), we were able to use a record 20 THz optical spectrum with total of 801 x 25 GHz spaced wavelength channels, each with dual-polarization-256 QAM modulation for high spectral density in all wavelength bands.

The 4-core MCF with standard cladding diameter is attractive for early adoption of new space-division multiplexing (SDM) fibers in high-throughput and long-distance links since it is compatible with conventional cable infrastructure and expected to have mechanical reliability comparable to standard single-mode fibers.

Beyond 5G, an explosive increase of data traffic from new information and communication services is expected and it is therefore crucial to demonstrate how new fibers can meet this demand. It is hoped that this result will help the realization of new communication systems able to support new bandwidth hungry services.

All of this bodes well for our future data capacity needs, particularly over longer data links. The team are now looking to both further boost the speeds of such cables and to extend the transmission range. Credits to one of our readers (Robert) for spotting this news.