Press Releases 2026

SoftBank Corp. and Ericsson to deploy
AI-powered external control system to optimize
Massive MIMO coverage

Successfully achieved an approximately 24% improvement in 5G downlink
throughput in a demonstration at Expo 2025 Osaka, Kansai, Japan.

January 29, 2026
SoftBank Corp.
Ericsson Japan K.K.

SoftBank Corp. ("SoftBank") and Ericsson Japan K.K. ("Ericsson") today announced that they have deployed an AI-powered, externally controlled coverage optimization system for Massive MIMO at multiple large-scale event venues in Japan, including major arenas and dome-type facilities in the Tokyo metropolitan area, which automatically enhances coverage patterns in response to traffic changes. This follows a successful commercial network trial at the Expo 2025 Osaka, Kansai, Japan ("Expo 2025") .

At large-scale event venues and theme parks, user distribution varies significantly between normal periods and during events, requiring flexible base station control in response to these distributions and changes. In particular, for events subject to weather-related cancellations or schedule changes, such as fireworks displays, or where specific area access restrictions occur, conventional methods that preset coverage pattern changes by time slot were sometimes unable to respond appropriately. Therefore, a system capable of automatically controlling and optimizing coverage patterns according to the situation was needed. To address these challenges, SoftBank and Ericsson have repeatedly conducted trials to validate automated traffic optimization using AI-driven external base station control*1.

When deployed at base stations installed in outdoor areas of the Expo 2025, the system delivered clear improvements in communication quality, including an approximately 24 percent increase in downlink throughput, from 76.9 Mbps to 95.5 Mbps, during periods of rapid traffic fluctuation.

Building on these results, SoftBank and Ericsson have begun operating the system at large-scale event venues where user distribution varies significantly by time of day.

Overview of the System

  • An external control device (server) uses user distribution data collected from base stations at one-minute intervals to automatically determine event occurrence using AI
  • Dynamically and automatically optimizes the horizontal and vertical coverage patterns of Massive MIMO base stations
Overview of the System

Overview of demonstration at Expo 2025

(1) Location

Massive MIMO-compatible base station installation areas within the Expo 2025 venue

(2) Content

An AI model was constructed using performance results obtained when multiple coverage patterns were changed in advance as training data. Based on user distribution-related data such as Massive MIMO beam estimation information*2 acquired by an ex-ternal control device from base stations at one-minute intervals, the system auto-matically determined event occurrence status and switched base station coverage patterns to optimal configurations.

(3) Key Results

Downlink throughput for 5G users across the entire area during event periods improved by approximately 24 percent*3. This result contributed to avoiding "packet stalling" phenomena where data transmission and reception stagnate due to congestion that tends to occur during rapid traffic fluctuations.

Roles of each Company

  • SoftBank

    Use case examination and demonstration evaluation of the system

  • Ericsson

    Provision of the system

The two companies will continue to actively expand deployment of the system.

[Notes]
  1. *1
    In September 2023, successful demonstration of automated traffic optimization through external base station control was achieved. For details, please refer to the press release dated February 22, 2024: "SoftBank Corp. and Ericsson Japan K.K. successfully demonstrate high-speed automatic optimization of 5G networks through external control of base stations."
  2. *2
    Reference signals used when terminals report the quality of Massive MIMO beams or channels back to the base station. These signals serve as an indicator of users' spatial distribution.
  3. *3
    Base station data acquired on days without and with the system applied were compared and evaluated under conditions with equivalent visitor numbers and event time periods.

ABOUT ERICSSON

Ericsson's high-performing networks provide connectivity for billions of people every day. For 150 years, we've been pioneers in creating technology for communication. We offer mobile communication and connectivity solutions for service providers and enterprises. Together with our customers and partners, we make the digital world of tomorrow a reality.
www.ericsson.com

  • SoftBank, the SoftBank name and logo are registered trademarks or trademarks of SoftBank Group Corp. in Japan and other countries.
  • Other company, product and service names in this press release are registered trademarks or trademarks of the respective companies.
About SoftBank Corp.'s Network Initiatives

To realize a society where everyone can live with peace of mind, SoftBank Corp. ("SoftBank") is enhancing and improving the reliability of its communications network. To provide a reliable communications environment for both ordinary times and during disasters, SoftBank is enhancing its terrestrial network across Japan, increasing its resilience in preparation for disasters and integrating it with Non-Terrestrial Networks (NTN). SoftBank's three key areas of focus for its communications network are as follows.

  • To enhance network quality for ordinary times, SoftBank is leveraging AI and big data to manage its entire communications network while strengthening its 5G and 4G base station network in urban areas and other locations. These initiatives are continually improving the customer quality of experience.
  • When demand for communications surges in extraordinary times, during large-scale events and natural disasters, for example, SoftBank works to secure a stable communications environment by deploying additional measures, such as mobile base station vehicles, portable communication equipment, drone-based base stations and free-of-charge Wi-Fi.
  • Under its vision for Ubiquitous Transformation (UTX), SoftBank is advancing the development of communications infrastructure that can be used in all environments, whether on land, sea or in the air. By integrating its terrestrial mobile network with NTN, including satellite communications and stratospheric communication platforms (HAPS), SoftBank will enable the rapid restoration of communications services during disasters and expand service coverage to mountainous regions and remote islands.