NICT researchers show world-record 159 Tbit/s transmission over 1045 km with three-mode optical fiber
With a standard 125 µm outer diameter, the fiber can be cabled using existing equipment.
Researchers at the National Institute of Information and Communications Technology (NICT) and Fujikura (both in Tokyo, Japan) Have transmitted 159 Tbit/s of data over a 1045 km distance using a three-mode optical fiber. Because the optical fiber has a standard 125 µm outer diameter, it can be cabled using existing equipment.
Multimode fibers have different propagation delays between optical signals in different modes, which makes it difficult to simultaneously satisfy large data rates and long-distance transmission; the NICT achievement shows that such limitations may be overcome.
Converting the results to the product of data rate and distance, which is a general indicator of transmission capability, results in 166 Pbit/s × km (Pbit = petabit). This is the world record in a standard outer diameter few-mode optical fiber and the largest data-rate over 1000 km for any kind of standard-diameter fiber.
To achieve a transmission capacity of 159 Tbit/s, mode multiplexing is used in combination with 16-QAM (quadrature-amplitude modulation), which is a practical high-density multilevel modulation optical signal, for all 348 wavelengths; multiple-input and multiple-output (MIMO) enables unscrambling of mixed modal signals even after transmission over more than 1000 km.
The results of this demonstration were selected for presentation as a postdeadline paper at the 41st Optical Fiber Communication Conference and Exhibition (OFC 2018; San Diego, March 11 to 15, 2018).1
1. G. F. Rademacher et al., "159 Tbit/s C+L Band Transmission over 1045 km 3-Mode Graded-Index Few-Mode Fiber," The Optical Networking and Communication Conference and Exhibition (OFC 2018), PDP, San Diego, Mar. 2018.