China Mobile, ZTE, first with 400G QPSK verification

Created September 27, 2022
Technologies and Products

ZTE and China Mobile, have jointly completed what they say is the world’s first prototype test of 400G QPSK (Quadrature Phase Shift Keying), and achieved the ultra-high-speed transmission over the distance of 3038 km based on G.652.D fibre.

In July 2022, China Mobile and ZTE jointly simulated the fibre length, loss and maintenance margin on its existing network in the lab, and employed a prototype to test 400G QPSK transmission. The result shows that the 400G QPSK optical module with 3D optical/electrical chipset can fulfil 49-span 3,038km transmission distance without electrical regeneration based on G.652.D optical fibre by adopting power fluctuation control algorithm and backward Raman amplification in some spans. It will allow Ultra-Long-Haul transmission for China Mobile to deliver massive large-bandwidth digital and intelligent optical networks.

China Mobile and ZTE have cooperated closely in the 400G LH transmission for a long term. In 2019, they tested the single-carrier 400G 16QAM in China Mobile’s network, and hit the industry’s record by transmitting 600 km. In October 2021, they verified the world’s first ultra-wide-spectrum single-wavelength 400G large-capacity optical transmission by using the 11 THz ultra-wide-spectrum C+L extended band in the existing network of China Mobile, with a transmission distance of over 1000 km.

ZTE says that as the digital economy booms and the national “east-data-west-computing” project launches, China has started the basic infrastructure of computing power network throughout the country. Since optical network is the cornerstone of the digital and computing power era, optical network based on broadband has become the focus of the entire industry. China Mobile is developing its computing power networks rapidly. A great deal of computing power services at the Yangtze River Delta put forward high requirements on data centre storage, AI training and rendering in Guizhou. Therefore, China Mobile considers it necessary to improve the bandwidth of its optical backbone network.

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This article was written
by Peter Dykes

Peter Dykes is a independent telecoms and technology journalist who has over that last 30 years written for a wide range of B2B publications and companies. A former BT engineer, he specialises in networks and associated support systems. He is currently Editor of Optical Connections.