The End of the "Climb": Rakuten Mobile Leverages Physical AI to Turn Antennas into Self-Thinking Assets

Physical AI enabling remote antenna tilt deployed at more than 14,000 Rakuten Mobile sites across Japan.

For decades, the physical layer of the mobile network - the antennas on the mast - was static. If a neighborhood grew, a new event drew a crowd, or a coverage hole emerged, the solution was always manual: book a technician, secure climbing gear, obtain permits, and wait weeks for a single sector adjustment.

We are moving away from manual maintenance toward the era of Physical AI. Rakuten Mobile is pairing Remote Tilt Systems (RTS) with our AI-powered RAN Intelligent Controller (RIC) to orchestrate a living, breathing network that optimizes itself in real-time.

Physical AI Revolution in RAN: Self-Thinking Masts

The industry is beginning to see that AI in Telecom is more than just LLMs or data analytics. Physical AI is the next frontier of the RAN, and it hinges on a capability that has long been considered impossible to automate: remote, real-time control of antenna direction.

By integrating robotic arms with our RIC, Rakuten Mobile can dynamically steer beam direction and beam depth. This allows the network to pivot its capacity in real-time, moving the signal footprint to follow the flow of human activity throughout the day.

Currently available at more than 14,000 sectors across Japan, the system functions in a closed-loop, autonomous lifecycle:

• Detection: The AI RIC monitors the network in real-time, identifying coverage gaps, site outages, or traffic spikes before they become service issues.
• Calculation: The AI determines the precise mechanical tilt required to reshape the signal footprint.
• Execution: The RTS adjusts the antenna vertically in seconds with zero human intervention.
• Healing: When a site goes offline, neighboring sectors autonomously rotate to fill the coverage gap, healing the network until the site is restored.

The results of initial reviews of live sites are definitive:

• 5G Traffic: Dynamic steering of tilt achieved a 23.5% increase in traffic utilization.
• Signal Quality: Improved by 5 points.
• Congestion: High-load bottlenecks reduced by 75%.
• Network Impact: Total operational costs savings of around 17% since deployment.

Why Antenna Control Matters‍

In traditional mobile networks, the antenna's physical orientation is a set-and-forget variable. By enabling remote, autonomous tilt adjustment, Rakuten Mobile has transformed the antenna from a static piece of hardware into a dynamic, software-defined asset. This removes the physical constraints of geography, allowing the network to perform spatial load balancing, a significant leap beyond current industry standards for automated network optimization.

By digitizing the antenna and empowering it with autonomous physical AI capability, Rakuten Mobile is moving toward a future where mobile networks are always optimized and available – and proactively anticipating demand.

Why is Azimuth Not Part of the Scope?

In Japan and other countries where antenna azimuth-related regulations are in place, changes to the azimuth must be made after the related license application to ensure full compliance with laws and regulations.

Once regulations per region allow remote changes to the azimuth angle, this advanced technique applies to remote azimuth change as well.