With the deployment of 5G, more and more attention has been paid to the construction of 5G carrying network. As an important part of the mobile backhaul network, the choice of 5G forward transmission solution will directly affect the investment and construction efficiency of operators.
From the perspective of optical fiber resources, the number of 5G fronthaul construction base stations will be increased by two to three times compared with 4G era. If only optical fiber direct drive mode is used, it will cause greater pressure on the existing network optical cable. 5G forwarding involves a large number of Du (distributed unit) / AAU (active antenna unit). The installation, opening and upgrading of these equipment must pay attention to the maintenance efficiency and cost of bearing products. Therefore, it is necessary to analyze the fronthaul solution to help operators reduce the construction and maintenance costs of 5G fronthaul and improve the deployment and operation efficiency.
5G fronthaul puts forward more stringent requirements for the bandwidth and delay of the carrying network. At present, 25Gbps eCPRI interface is preferred, and the latency is required to be less than 100 μs
Semi-active WDM solution
Solution Feature
Similar to passive WDM, network management monitoring and optical layer protection functions are added on the basis of maintaining end-to-end low passive WDM cost.
DU side equipment is active with optical layer protection and automatic switching. Power failure of equipment only affects network management but does not affect service.
Modular structure, 1:6/1:12/1:18 optional, flexible configuration of function units.
Application ScenarioDU small-scale centralized deployment or limited fiber resource areas.
No power for remote system with the ability of outdoor deployment. Passive mux/demux can be deployed together with AAU to handle single-station service, or can be deployed at optical intersection site to converge multi-station services.
Meet the requirement of reliability and manageability for 5G forward network.
Passive WDM solution Solution FeatureColored light modules are used in the AAU and DU side to connect each other based on the passive WDM.
Significant saving of fibers with optional channels of 6/12/18/24/48
Similar to optical direct drive with high bandwidth and low delay.
The solution is passive. It’s simple to use and fast to deploy.
Application ScenarioMainly applicable to the end-to-point C-RAN network scenario requirement.
No power for remote system with the ability of outdoor deployment. Passive mux/demux can be deployed together with AAU to handle single-station service, or can be deployed at optical intersection site to converge multi-station service.