OFweek Optical Communications Network News With the advancement of the "Broadband China" strategy and the development of optical fiber technology, my country's network entered fiber-opticization in 2016, which benefited from the vigorous construction of optical networks by the three major operators .
China Telecom and China Unicom continue to promote the "optical reform" work and create an "all-optical province" nationwide, while China Mobile has also increased its investment in fixed networks. From the first quarter of 2016 This can be seen from the fact that the number of China Mobile's home broadband customers has exceeded 60 million.
"Optical modification" accelerates the process of new services such as 4K
Operators' "optical reform" is progressing rapidly. For example, China Unicom has built 8 An all-optical network province is expected to complete the nationwide optical network transformation this year (ten northern provinces).
Fiber to the home is not the end of broadband development. The "optical reform" work has cleared obstacles for the development of new services. Operators will increase their focus on 4K video in the next step. Waiting for the development of new business.
Operators have made remarkable progress in 4K. In March 2016, China Unicom established a 4K laboratory and established a 4K industry alliance to unite all parties in the industry chain to promote the development of 4K; recently, it cooperated with Huawei Reached strategic cooperation to jointly innovate in the field of 4K video; released the "China Unicom 4K IPTV Technology White Paper".
Guangdong Telecom also recently announced that the number of IPTV 4K users exceeded one million.
Operators’ rapid progress in 4K also proves the value of their “optical transformation”.
The industry has made clear demands for 400G optical systems
From the perspective of optical communication systems, my country has currently deployed the world's largest 100G Network, Wei Leping, director of China Telecom Science and Technology Commission, once said that the backbone network is evolving steadily. In 2013, the maximum segment capacity of network links reached 12T, and 100G began to be deployed on a large scale and became the dominant technology of the backbone network.
By 2017, the capacity of large segments will reach 46T, and the demand for 400G will begin to appear.
Wang Guangquan, director of the Network Technology Research Department of China Unicom Network Technology Research Institute, pointed out that in the beyond 100G era, CD/PMD is no longer the main limiting factor, and nonlinear effects and fiber attenuation will become the influencing factors. The main factor of system transmission performance.
How to balance spectrum efficiency, transmission distance and system capacity under the limitations of Shannon limit has become a key issue in 400G application deployment.
Facing the coming 400G era, the three major operators have begun 400G network testing to prepare for future commercial 400G networks. For example, China Mobile has conducted 400G testing on the main line from Xi'an to Zhengzhou.
The arrival of the 400G era has put forward higher requirements for existing networks.
This not only means that equipment performance needs to be improved, but also that the industry needs Find a new type of optical fiber that is more suitable for large-capacity and long-distance transmission.
Currently, mainstream optical fiber and cable manufacturers in the industry are actively developing related products to provide strong support for improving the transmission performance of optical network systems and extending system transmission distances. .
The research and development of new optical fibers is in full swing
In industry laboratory tests for 400G networks, based on existing optical fiber (G.652 and G.655) systems cannot meet the requirements of 400G long-distance transmission systems.
Using large effective area optical fibers to increase the input optical power can extend the transmission distance and significantly improve system transmission. performance.
The new G.654 optical fiber has become the main choice for current 400G ultra-high-speed backbone transmission optical fiber.
At present, many fiber optic cable manufacturers around the world They have already carried out the research and development of new optical fiber products such as G.654.
Yangbei’s ultra-strong, ultra-low attenuation, large effective area optical fiber G.654 optical fiber meets or even exceeds ITU-T G. 654.B standard; Hengtong’s UUA ultra-low loss ultra-large effective area single-mode fiber G.654-135 is my country’s first independently developed original ultra-low loss large effective area single-mode fiber; Zhongtian Technology Lu low-loss G. 654 optical fiber meets ITU-T G.654B and G.654E standards (draft)
China Unicom is the pioneer in the introduction of G.654 optical fiber, currently in Shandong and Xinjiang The primary and secondary trunk lines in the two places have started pilot verification of existing networks to evaluate their transmission performance and environmental adaptability.
Optical networks have a long construction cycle and lifespan, and the investment is very large. Therefore, operators need to fully verify and be extra cautious when introducing new optical fibers.
Wang Guangquan said that China Unicom will continue to promote the verification of new optical fibers and collect performance data from live network tests within two years, focusing on attenuation; comparing the performance differences between G.652 and G.654 optical fibers within the same cable, Verify the possibility and environmental adaptability of new optical fiber terrestrial applications; at the same time, the existing network will also conduct 400G tests based on G.652 and G.654 to verify the optimal optical power of different optical fibers and verify the transmission performance of G.654 optical fiber.
