Welcome Message from General Chair

On behalf of the organizing committee, it is my great honor and pleasure to welcome you to the 2025 IEEE International Symposium on Radio-Frequency Integration Technology (RFIT 2025), which will be held in the beautiful city of Kagoshima, located in the southern region of Kyushu, Japan.

Since its inception in 2005, RFIT has established itself as a premier forum for the presentation and discussion of innovations in radio-frequency (RF), millimeter-wave, and THz integrated circuit technologies, as well as their enabling semiconductor devices and system-level applications. The symposium uniquely bridges academic research and industrial implementation, fostering collaboration across disciplines and continents.

Japan has proudly hosted RFIT twice in the past, first in Sendai in 2015 and most recently in Hiroshima in 2020. Both events were remarkable in showcasing Japan’s technological leadership in RF integration field, and the RFIT 2025 in Kagoshima proudly continues this tradition. Situated in Kyushu, a region known as Japan’s historical gateway to science, technology, and international exchange, Kagoshima offers an inspiring setting with a strong connection to the semiconductor, space, and quantum technology sectors.

This year’s symposium is particularly timely as we face a new frontier in wireless systems, marked by the emergence of 6G communications and the rapid growth of quantum computing applications. These advancements require new levels of performance in RF and mixed-signal circuits, including cryogenic-compatible devices, high-efficiency amplifiers, and ultra-integrated semiconductor platforms.

The RFIT 2025 will feature a comprehensive technical program including keynote speeches by global leaders, invited sessions, oral and poster presentations, and special sessions addressing frontier topics such as 6G system-on-chip architectures, RF for quantum computing, and advanced packaging and integration technologies. We especially welcome the participation of early-career researchers and students, as their vision and creativity are essential to driving future innovation.

We are confident that RFIT 2025 in Kagoshima will be a truly rewarding experience—technically, professionally, and culturally. We look forward to seeing you in Japan’s southern gateway for a memorable and impactful symposium.

With warmest regards,

Kenjiro Nishikawa
General Chair,
2025 IEEE International Symposium on Radio-Frequency Integration Technology

Welcome Message from Technical Program Cimmittee Chairs

On behalf of the IEEE RFIT 2025 Technical Program Committee (TPC), it is our great pleasure and an honor to welcome all the participants in the RFIT series. RFIT 2025 TPC received 97 submissions, including invited papers. After careful review, 22 invited papers and 56 regular papers were selected to form 12 high-level technical sessions (10 oral and 2 poster sessions). We would like to express my gratitude to all the reviewers and TPC members for their enthusiasm and dedication in developing an outstanding technical program on time. We would also like to extend my personal and deepest gratitude to the members of Organizing committee.

RFIT 2025 begins with 2 workshops titled “Enabling 6G: Devices, Systems, and Measurement Techniques” and “Microwave/RF Technologies for Quantum Computing” on August 25th. Following the opening, the plenary session will feature two talks titled “Toward the Realization of the “New Silicon Island Kyushu"” and “New Concept of Industry-Level Large-Scale Quantum Computer”, delivered by Mr. Yoshinori Taguchi and Dr. Masahiro Horibe, respectively on August 26th.

We hope you will enjoy this engaging symposium and participate in fruitful technical discussions.

With warmest regards,

Yasunori Suzuki and Shintaro Shinjo
Technical Program Committee Chairs,
2025 IEEE International Symposium on Radio-Frequency Integration Technology

Plenary Speaker 1

Toward the Realization of the “New Silicon Island Kyushu"
— To realize a vibrant regional economy and society with semiconductors from Kyushu —



Mr. Yoshinori Taguchi
Director, Economic Policy Division, Economic Policy Department, Kyushu Bureau of Economy, Trade and Industry (METI-Kyushu)

Abstract: The current state of the semiconductor industry in Kyushu and the activities of the “Kyushu Consortium for Human Resource Development of Semiconductors,” which aims to develop and secure semiconductor human resources, will be introduced, along with the history of “Silicon Island Kyushu” and the challenges it faces.
In June 2021, the Ministry of Economy, Trade and Industry (METI) formulated the “Semiconductor and Digital Industry Strategy” and has been promoting efforts nationwide to secure the manufacturing basis for semiconductors essential to industry and society, and to develop and secure semiconductor human resources.
In Kyushu, ”Kyushu Consortium for Semiconductor Human Resource Development” with the participation of almost 150 industrial, educational, administrative, and financial institutions, is at the core of various initiatives as the nation's top runner in this field. The latest developments are introduced here.

Plenary Speaker 2

New concept of industry-level large-scale quantum computer



Dr. Masahiro Horibe
Deputy Director, Global Research and Development Center for Business by Quantum-AI Technology (G-QuAT), The National Institute of Advanced Industrial Science and Technology (AIST)

Abstract: With the active research and development of quantum computers, the efforts of quantum technology field is expanding into industrialization. However, if existing 200- to 300-qubit class quantum computer system technologies, components, and devices are used as is, even if a quantum computer could be realized, the challenges of cost, power consumption, weight, and size would prevent industrialization. Therefore, we propose a new system concept and strategically construct the supply chain necessary for it.

Workshop 1

Enabling 6G: Devices, Systems, and Measurement Techniques

Abstract: This workshop explores the emerging technologies driving the realization of 6G, with a focus on device innovations, system-level tests, and advanced measurement methods. Featuring talks from leading experts, the session aims to provide a comprehensive view of key technical enablers and challenges shaping the 6G.

• 5G evolution and 6G
  Mr. Takehiro Nakamura (NTT docomo, Japan)
  
• Digital RF Technologies for Q/V-Band LEO SATCOM Constellation
  Dr. Akihito Hirai (Mitsubishi Electric Corporation, Japan)
  
• Innovative GaN HEMT-Based S-LMBA Design for Wideband, High-Efficiency, and High-Power Performance
  Mr. Hirotaka Asami (Sumitomo Electric Industries, Ltd., Japan)
  
• Demonstration of a Sub-Terahertz Channel-Bonded Transmission System with Potential for Over 100 Gbps
  Dr. Atsushi Fukuda (NTT docomo, Japan)
  
• Terahertz Beam Engineering: A New Quality Productive Force
  Prof. Chong Han (Shanghai Jiao Tong University, China)
  
• Modern Methods for Component Measurements using Vector Network Analyzers for 6G Test
  Dr. Joel Dunsmore (Keysight Technologies)
  

Workshop 2

Microwave/RF Technologies for Quantum Computing

Abstract: This workshop highlights recent advances in microwave and RF technologies essential for superconducting quantum computing. Topics include cryogenic amplifiers, superconducting circuits and cables, and scalable qubit control techniques, offering a comprehensive view of key components enabling next-generation quantum systems.

• Superconducting digital circuits for quantum computer
  Prof. Fujimaki (Nagoya University)
  
• Basic operation for quantum computer
  Dr. Tamade (Riken)
  
• Cryogenic low noise amplifier
  Dr. Niklas Wadefalk (LNF)
  
• Challenges and opportunities in cultivating an emerging quantum ecosystem in Japan: the quantum control journey for 1000 qubits
  Mr. Koji Sato (Keysight Technologies)
  
• Qbit control for superconducting quantum computer
  Prof. Makoto Negoro (The University of Osaka)
  
• Superconducting cable for  quantum computer
  Dr. Yuki Tanaka (Fujikura)
  
• Microwave circuits for quantum computer
  Dr. Inomata (AIST)