How to connect fiber optic cable to RRU

Connect the fiber optic cable to the RRU via the CPRI port, ensuring proper handling, outdoor-rated cable use, and secure connections to the BBU/DU.

Identify the Correct Ports

Most RRUs have CPRI ports (e.g., CPRI0, CPRI1) for fiber optic connections to the baseband unit (BBU/DU) . These ports are bi-directional and handle both transmit and receive signals. Check the RRU model to confirm the number and labeling of CPRI ports, as some models may have only one.

Prepare the Fiber Optic Cable

Use a field optical cable designed for outdoor use, which is durable, weather-resistant, and suitable for mobile installation . Ensure the cable has the correct connector type compatible with the RRU, typically SC/APC or SC/UPC. Avoid bending the cable sharply to prevent signal loss or damage.

Connecting the Cable

1. Power Off Equipment: Before connecting, ensure the RRU and BBU/DU are powered off to prevent damage.
2. Open the Connector: If using a quick-lock fiber optic connector, open it carefully to expose the fiber .
3. Insert into RRU: Plug the fiber optic connector into the CPRI port on the RRU. Ensure it clicks or locks securely.
4. Route the Cable: Run the cable along the designated path, avoiding sharp bends and securing it with cable ties or clamps suitable for outdoor conditions.
5. Connect to BBU/DU: At the baseband side, insert the other end of the fiber into the corresponding CPRI port on the BBU/DU or into the ODF unit if using CRAN architecture .

Verify the Connection

After connecting, power on the RRU and BBU/DU. Check the status indicators on the RRU to confirm the fiber link is active and stable . A steady light typically indicates a successful connection.

Safety and Best Practices

• Always handle fiber optic cables with care to avoid fiber breakage or eye injury.
• Use outdoor-rated cables for RRUs installed on towers or rooftops.
• Maintain proper installation clearance around the RRU to prevent mechanical stress on the cable .
• Label both ends of the fiber for easy identification during maintenance. By following these steps, you ensure a reliable, high-speed optical connection between the RRU and the baseband unit, which is critical for optimal cellular network performance.