The key facts

  • A total speed of 3.2 Pbit/s was achieved — that is 3.2 million gigabits per second over a single fiber
  • Fiber with 24 cores, 10.3 km long, was used, along with the S, C, and L bands
  • In March, the same team reported 2.5 Pbit/s — the new result is roughly 28% higher

The test and the claimed result

Specialists from China conducted a test of real-time data transmission in both directions over an optical fiber with 24 cores and achieved a total speed of 3.2 petabits per second, that is, 3.2 million gigabits per second. The researchers assess this result as a new world record for real-time bidirectional data transmission capacity through a single optical fiber. Kun.uz reports this citing a publication by Chinese sources.

Who took part and how the system was built

The test involved specialists from the National Information Optics and Communication Networks Laboratory, part of the Chinese corporation China Information and Communication Technologies (CICT), the Pengcheng Laboratory, and the company Fiberhome Fujikura Fiber Optic Technology. For the test, they used multimode optical fiber 10.3 km long, over which data was transmitted simultaneously in both directions; the claimed 3.2 Pbit/s is the total capacity of such transmission.

The technical basis of the record

The key feature of the system is 24 separate cores inside a single fiber, each of which serves as an independent channel for transmitting light signals. The researchers used three wavelength bands, designated S, C, and L, combining this approach with parallel transmission technology across different cores; as a result, thousands of parallel channels were formed within a single fiber. For stable real-time transmission, commercial coherent optical modules and improved signal shaping methods were used, and optimization of the core arrangement helped reduce mutual interference between them.

Comparison with existing systems and the previous result

According to the comparison cited by the researchers, typical single-core optical fiber systems of the G.652 standard operating in the C and L bands have a capacity of about 100 terabits per second — the new system surpasses this figure by 32 times. In their own optical modules, the team tested real-time transmission at a speed of 400 Gbit/s per wavelength in the S band and 1.2 terabits per second in the C and L bands. Notably, the same group of researchers in March of this year presented a result of 2.5 Pbit/s on the same 24-core fiber: the new figure is approximately 28% higher, demonstrating the team's rapid progress over the course of a year.