Recently, ZTE and China Mobile completed the world's first 400G QPSK (Quadrature Phase Shift Keying) quasi-real-time system transmission verification, realizing ultra-high-speed transmission based on G.652.D fiber with a total length of 3038 km , which proves the advantages of 400G QPSK in the long-distance transmission of the current backbone optical network.
With the vigorous development of the digital economy and the launch of the national "East Digital and Western Computing" project, the construction of basic resources for computing power networks in my country has been comprehensively deployed. Optical networks are the cornerstone of the computing era, so broadbandization of optical networks has become the consensus of the entire industry. In this context, China Mobile's computing network has developed rapidly, and a large number of computing power businesses in the Yangtze River Delta have put forward demands on data center storage, AI training, and rendering in Guizhou and other places. It is imperative for China Mobile to improve the bandwidth of the backbone optical network.
In order to solve the above problems, ZTE and China Mobile simulated the fiber length, loss and maintenance margin of the existing network in the laboratory in July 2022, and used a quasi-real-time prototype for 400G QPSK transmission verification. The verification results show that the 400G QPSK optical module equipped with 3D optoelectronic chip fusion package adopts the power fluctuation control algorithm, and uses the backward Raman amplification technology in some spans, and finally can achieve 49 spans without electricity in the G.652.D fiber. Following the transmission distance of 3038km, it can meet the ultra-long-distance transmission requirements of China Mobile's massive and large-bandwidth services, promote the development of China Mobile's optical network, and lay the foundation for the development of the global digital and intelligent optical network.
China Mobile and ZTE have maintained long-term in-depth cooperation in the field of 400G long-distance transmission. As early as 2019, the two parties used single-carrier 400G 16QAM to conduct tests on China Mobile's existing network, and achieved the longest transmission distance of 600KM at that time, which once refreshed the industry's longest transmission distance on the existing network. Subsequently, in October 2021, the two parties completed the world's first ultra-broad-spectrum single-wavelength 400G high-capacity optical transmission verification using the 11THz ultra-broad-spectrum C+L extended band on China Mobile's existing network, achieving a transmission distance of over 1,000km.
In the future, ZTE will continue to take root downwards, in-depth technical research and practical exploration of optical networks, and work with global operators to build a digital and intelligent optical network to jointly promote the new development of the digital and intelligent economy.
