The release of the new infrastructure policy has accelerated China's 5G deployment, 5G construction, bearing first. The gradual commercial use of 5G network can effectively promote the rapid development of new technologies and applications such as industrial Internet, artificial intelligence and Internet of Things. The extensive development of 5G application can improve people's living standard, increase convenience in life and improve happiness index.

In 2020, 550,000 5G base stations will be built and opened nationwide. As of the end of February, 80% of my country's 5G network construction was implemented as planned. The number of 5G base stations of China Mobile has exceeded 80,000. In 2020, the goal of "building 300,000 5G base stations, and the 5G network covering cities at the prefecture level and above" will remain unchanged.

The optical network is an important part of the mobile communication network. In the optical network transmission, the optical module plays the role of photoelectric conversion. At the sending end, the electrical signal is converted into an optical signal, and after transmission through the optical fiber, the receiving end converts the optical signal again. Therefore, the optical module is the basic component of the high-speed interconnection of the mobile communication network.

In the 3G era, the interconnection between the BBU and the RRU used 1.25G optical modules, and in the 4G era, 10G optical modules were used.At present, 5G will still use 10GB optical modules in the early trials, but the 5G prequel mentioned in the 5G white paper is more about using 25GB optical modules.

Here, ETU-Link introduces the types of optical modules used in 5G networks.

1. 25G SFP28 SR 10KM

2. 25G SFP28 LR 10KM

3. 25G SFP28 CWDM 10KM

4. 25G SFP28 BiDi 10KM

Based on the convergence function, 10G or 25G rate optical modules can be used in the initial 5G access segment, such as 10G SR (300m, VCSEL laser, MMF), 10G or 25G LR (10km, DFB laser, SMF), etc.In 5G, the backhaul covers the access layer, aggregation layer and core layer of the metropolitan area network. If the DU/CU is co-located, the mid-transmission optical module is not required.

The technical requirements of the optical modules required for the intermediate transmission are not much different from the optical modules used in the existing transmission network and data center. However, due to the increase in the demand for bearer bandwidth, the integration and flattening of the transmission network, and the sinking and extension of WDM/OTN in the metropolitan area network, The speed requirements of optical modules will be improved. The access layer is 25Gb, and the core aggregation layer 100G will become the mainstream. In some hot spot areas, the core aggregation will even reach the demand of 400G.