December 2025 Vol. 23 No. 12

View from the Top

• Yoshiaki Maeda, President and Chief Executive Officer, NTT DOCOMO, INC.

  

  Abstract
  In July 2025, the NTT DOCOMO Group adopted a new corporate identity and logo that features NTT’s Dynamic Loop. The Group supports social life with its advanced communication technologies that have been cultivated in a highly competitive mobile phone market. We interviewed Yoshiaki Maeda, president and chief executive officer of NTT DOCOMO, to learn about NTT DOCOMO’s business environment and his mindset as president.

Front-line Researchers

• Jun-ichi Kani, Senior Distinguished Researcher, Access Network Service Systems Laboratories, NTT, Inc.

  

  Abstract
  In March 2023, NTT EAST and NTT WEST released the Innovative Optical and Wireless Network (IOWN) All-Photonics Network (APN) service, APN IOWN 1.0, which attracted public attention thanks to its high speed, large capacity, and low latency. At Expo 2025 Osaka, Kansai, Japan, held from April 13 to October 13, 2025, the IOWN APN connected key facilities, such as pavilions and event facilities, within the Yumeshima site. Thanks to its low power consumption, high-capacity, high-quality, and low-latency transmission capabilities, it offered an environment where various content and events could be shared, creating a sense of unity and immersion without the sense of distance. With regard to the access-side architecture of the APN, various approaches are currently being considered and discussed. Leading the discussions and attempting new approaches, Jun-ichi Kani, a senior distinguished researcher at NTT Access Network Service Systems Laboratories, talked about his efforts in regard to developing the IOWN APN and his belief that taking on new challenges and pursuing interesting things—even if they are not directly related to one’s research topic—may lead to new discoveries and research ideas.

Rising Researchers

• Atsushi Takagi, Distinguished Researcher, Communication Science Laboratories, NTT, Inc.

  

  Abstract
  The human brain issues motor commands that enable the body to perform everyday movements and exercises. However, there are differences in dexterity between the dominant and non-dominant hands. Taking this simple but fundamental feature as a starting point, we spoke with Atsushi Takagi, a distinguished researcher at NTT Communication Science Laboratories and a leader in the field of the brain’s control of movements. He has been elucidating the mechanism behind dexterous movements from a completely new perspective—disruptions in the timing of motor commands issued by the brain—and making one discovery after another.

Feature Articles: Creating Innovative Next-generation Energy Technologies

• Current Situation of Next-generation Energy Research at NTT Space Environment and Energy Laboratories

  

  Abstract
  NTT Space Environment and Energy Laboratories was established in 2020 with the goal of creating innovative technologies to restore the global environment and achieve a sustainable and inclusive society. It has tackled unconventional research themes not previously pursued by NTT research laboratories and has begun to yield concrete results. This article focuses specifically on energy-related technologies and introduces the current situation of various initiatives poised to transform the future of the global environment.

• Maximizing Renewable Energy Use in Datacenters through Watt-bit Collaboration

  

  Abstract
  The proliferation of generative AI (artificial intelligence) has led to a surge in power demand for datacenters (DCs), making the effective use of renewable energy (RE) a critical challenge. NTT Space Environment and Energy Laboratories is tackling this challenge by maximizing RE usage through watt-bit collaboration, using two approaches: dynamic distributed control of DC workloads and DC placement optimization. This article explains the background, challenges, and overall technical framework of this effort.

• Lightning Control and Charging Technologies that Protect People and Equipment and Harness Energy

  

  Abstract
  At NTT Space Environment and Energy Laboratories, we have greatly advanced technologies that protect communication facilities from lightning. We are now conducting research on lightning control and lightning charging technologies that will eliminate lightning strikes on critical infrastructure and cities, while also harnessing lightning as a source of energy. This article introduces our drone-based experiments to trigger and guide natural lightning, as well as experiments to generate compressed air that stores lightning energy by using lightning surge currents.

• Space Solar Power System with Optical Technology

  

  Abstract
  A space solar power system (SSPS) represents a next-generation energy technology that wirelessly transmits solar energy collected in space to the Earth, offering a stable power supply independent of weather and the day-night cycle. At NTT Space Environment and Energy Laboratories, we are advancing research on solar-pumped lasers, long-distance wireless energy transmission, and high-intensity beam-to-electricity conversion. In this article, we present the development of a photovoltaic cell optimized for 1064-nm laser light. Our prototype device, with an active area of 1 cm², achieved world-class conversion efficiency, demonstrating a key step toward practical SSPS implementation.

• Toward Fusion Energy—Integrating Knowledge through AI and Data Science

  

  Abstract
  Fusion energy is expected to be a clean, safe, and sustainable energy source. However, it requires stable confinement and precise real-time control of ultra-high-temperature plasma. Recent advances in artificial intelligence (AI) and data science provide new tools for addressing these challenges. NTT has developed two methods: AI-based magnetic equilibrium prediction using a Mixture of Experts model, which achieved centimeter-level accuracy on the JT-60SA tokamak in collaboration with the National Institutes for Quantum Science and Technology, and sparse modeling for estimating mathematical models directly from plasma data. Together, these methods accelerate fusion research and contribute to future energy innovation.

Regular Articles

• Initiatives for the Wireless Base Station Optimization AI to Balance Radio Resource Efficiency and Power Efficiency

  

  Abstract
  In response to the growing volume of mobile network traffic, improving the efficiency of wireless base station utilization through parameter optimization has become increasingly important. However, parameter optimization for wireless base stations is largely carried out manually, which limits its applicability to specific areas. This article introduces our initiative on the Wireless Base Station Optimization AI, which automates the derivation of base station parameters using artificial intelligence (AI), with the aim of expanding the range of areas where optimization can be applied.

Global Standardization Activities

• Report of the First Meeting of ITU-T Study Group 5 (Environment, Climate Action, Circular Economy and Electromagnetic Fields) Held in Geneva, 3–12 June 2025

  

  Abstract
  The International Telecommunication Union - Telecommunication Standardization Sector (ITU-T) Study Group 5 (SG5): “Environment, climate action, circular economy and electromagnetic fields” aims to develop international standards to promote an environmentally sustainable, resilient, and inclusive telecommunications/information and communication technology (ICT) sector. It focuses on enabling safe, resilient, efficient, and responsible ICT development through global standardization. This article reports on the deliberations of the first meeting of ITU-T SG5 held in Geneva, Switzerland 3−12 June 2025.

External Awards

• External Awards