25G optical module/100G optical module

In the era of cloud computing, the demand for data center networks is growing explosively, entering the period of IDC demand expansion, and the demand for high-speed optical modules such as 25G optical modules and 100G optical modules is growing rapidly.

1. Characteristics of 5G network

The 5G mobile network provides three types of services: enhanced mobile broadband (eMBB), ultra-reliable and low-latency communication (uRLLC), and massive machine-type communication (mMTC). large; uRLLC business is oriented to real-time control applications such as industrial automation, with low latency and high reliability; mMTC is oriented to IoT applications, with many connections and low traffic.

The 5G Radio Access Network (RAN) is re-divided into Active Antenna Unit (AAU), Distributed Unit (DU), and Centralized Unit (CU). The core network is gradually shifting from centralized deployment in the 3G/4G era to cloud-based and distributed deployment. , The core network of different services is moved to different locations to meet the requirements of low-latency services and improve user experience.

1. Large bandwidth

The bandwidth of the base station depends on the configuration of parameters such as wireless spectrum bandwidth, spectrum efficiency, and number of antennas. For a base station with 64 TR 100 M bandwidth, the peak bandwidth can reach 6 Gbit/s, and the average bandwidth is 3 Gbit/s. According to the definition of the International Telecommunication Union (ITU): The maximum peak bandwidth of a 5G base station can reach 20 Gbit/s. In actual situations, it is difficult for the base station rate to reach the maximum peak rate. In addition, considering factors such as cost and power, 5G base station types will coexist, and base station bandwidths will exist from 1 to 20 Gbit/s.

5G base stations are divided into high-frequency base stations and low-frequency base stations: 5G low-frequency base stations are used for wide coverage. In the early stage, 5G low-frequency base stations and 4G base stations will be deployed at the same site. It is used for supplementary heat, and the initial scale is small, but some of them need 25 GE interface access.

2. Low latency

The delay of different 5G services varies greatly. The 3rd Generation Partnership Project (3GPP) TR 38.913 defines eMBB end-to-end (E2E) delay as 10 ms, uRLLC as 1 ms, and eMBB air interface delay as 4 ms. The air interface delay of uRLLC is 0.5 ms; however, for different uRLLC services, 3GPP TS 22.261 V16.0.0 provides different delay definitions.

3. Traffic Mesh

5G CU and DU can be deployed flexibly and can be separated or combined. The separated CU and DU have the characteristics of many-to-one and one-to-many, and there are dual-homing and redundancy requirements. According to the step-by-step introduction of eMBB, uRLLC, and mMTC services, the core network will gradually transition from centralized deployment to distributed deployment. There is a many-to-many relationship between the CU and the core network, and there is traffic interaction between the core networks. The Mesh trend of service traffic in the 5G era is more obvious.

4. Network slicing

The first generation mobile communication network (NGMN), IMT 2020, and the third generation partnership (3GPP) all proposed a network slicing architecture based on software-defined network (SDN)/network function virtualization (NFV) for 5G networks. Innovative and rapid deployment services provide the foundation. At the same time, the network slicing service can provide characteristic services such as management isolation, resource isolation, computing isolation, forwarding isolation, and control isolation. The isolation of different resources can be flexibly configured to meet different types of business security, reliability, and key performance indicators (KPIs). and other aspects of differentiated requirements to ensure business security and service quality.

5. Gradual evolution from NSA to SA

The 5G network construction mode is divided into independent deployment (SA) mode and non-independent deployment (NSA) mode: in SA mode, a new wireless and core 5G network is built, and the two networks of 4G network and 5G network operate independently; NSA is a gradual evolution. The network technology solution, through the existing resources of 4G, is only enhanced on the 4G network, and provides services for 5G in the form of partial expansion, and gradually evolves to 5G as the 5G business continues to mature.

The 5G bearer network uses 10 GE and 25 GE interfaces to access the base station on the user network side interface (UNI). The network side will introduce 25 GE, 50 GE, and 100 GE interconnection technologies. In the future, the metropolitan area may move to 200 GE and 400 GE Link evolution, so 5G network construction will require optical modules with the characteristics of integration, miniaturization, high speed, long distance, low cost, and low power consumption, such as 25G optical modules and 100G optical modules.

2. Development trend of 25G optical module/100G optical module

The rate of the optical module has always been the focus of the market, according to the rate can be divided into 622Mb/s, 1.25Gb/s, 2.5Gb/s, 10Gb/s, 40Gb/s, 100Gb/s and so on. At present, the factors that promote the speed upgrade of optical modules mainly come from several aspects: On the one hand, the "Broadband China" strategy requires the realization of 100M fiber-optic access to the home, which increases the pressure on the optical interface from the access layer, and the optical interfaces at all levels from bottom to top carry on pressure, driving the demand for high-speed optical modules; with the deployment of 5G, operators need to deploy wider bandwidth to realize applications of large-flow data, such as telemedicine, VR, 4K video, etc., so mobile networks must have more High speed, which also promotes the development of 25G optical modules/100G optical modules.