Optical modules required for an RRU

RRUs require optical modules that support high-speed data transmission, industrial temperature ranges, and multiple fiber cores, typically ranging from 1. 25G to 10G for 4G and 5G networks.

Key Requirements for RR

U Optical Modules1. Data Rate and Type: Optical modules for RRUs must match the data rate of the fronthaul interface. In 4G networks, common modules include 1.

25G, 2. 5G, 6G, and 10G optical modules, with 10G modules being the mainstream for high-capacity links and 5G pilot deployments. These modules connect the BBU (Baseband Unit) to the RRU, enabling high-speed transmission of baseband data and control signals.

2. Industrial Temperature Support: RRUs are typically mounted outdoors on towers and are exposed to extreme temperatures. Optical modules must therefore support industrial temperature ranges, often from -40℃ to +85℃, to ensure reliable operation in harsh environments.

3. Fiber Core Requirements: Depending on the network design, an RRU may require 2–6 optical fiber cores for transmission. To optimize fiber usage, CWDM (Coarse Wavelength Division Multiplexing) solutions are often employed, allowing multiple wavelengths to share a single fiber and reducing the need for additional fiber infrastructure.

4. Compatibility and Deployment Considerations: Optical modules must be compatible with the RRU's high-speed interface unit and signal processing unit, ensuring seamless transmission of downlink and uplink baseband data. They also support serial networking between multiple RRUs and BBUs, which is critical for distributed base station architectures.

5.

Future-

Proofing for 5G: While 4G networks commonly use 10G optical modules, 5G RRUs may require higher-capacity modules to support massive MIMO and millimeter-wave frequencies. Optical modules should therefore be selected with scalability in mind to accommodate future upgrades.

Summary

To summarize, the optical modules required for an RRU should: Support high-speed data rates (1. 25G–10G for 4G, higher for 5G)Operate reliably in industrial temperature rangesConnect via 2–6 fiber cores, often using CWDM for efficiencyBe compatible with the RRU's internal modules and fronthaul interfaceAllow for scalable deployment to support future network upgrades These specifications ensure that RRUs can efficiently transmit baseband signals to and from BBUs, maintain signal quality, and operate reliably in outdoor environments.