Workshop Program

Since the enforcement of the new regulations for radiative Wireless Power Transmission (WPT) systems in 2022, the commercialization of radiative WPT systems using microwave frequency bands such as 920 MHz and 5.7 GHz have been progressing in Japan. The major applications of microwave WPT systems are power supply and/or charging to IoT devices. On the other hand, the radiative WPT systems using millimeter wave, such as the 24 GHz band, is are being considered for applications requiring higher received power levels, including the wireless charging of mobile devices. This is because higher frequency bands enable the realization of higher-gain transmitting antennas.
This session will present the latest developments in regulatory frameworks, research and development of device and system technologies related to millimeter-wave WPT.

Keyword ： Millimeter Wave, Wireless Power Transmission / Transfer (WPT), Radiative WPT, RF-Beam WPT, Regulation, IoT, Mobile Device

Systems that use radio waves have come to be used in a wide range of fields, including various types of communication, sensing, and power transmission. Antennas are an essential technology for using radio waves, and it is also essential to measure their characteristics for design validation or certification.
This course will explain the basics of measuring antenna characteristics such as impedance characteristics and radiation patterns for small antennas and large antennas.

Keyword ： Antenna, Measurement, Impedance, Radiation Pattern, Small Antenna, Large Antenna

Microwave power amplifiers are key components that play an essential role in a wide range of microwave applications, including wireless communications and wireless power transfer.
This lecture will introduce the fundamental circuit configurations of microwave power amplifiers, design guidelines for matching networks, and the basic concepts required to achieve high-efficiency operation. Practical design approaches will also be discussed, together with recent research results.
Keyword ： Power Amplifier, Matching Network, High Efficiency

Microwave power amplifiers have traditionally evolved as key devices supporting communication infrastructure. In recent years, however, leveraging their technological foundation, they have rapidly expanded into a wide range of fields beyond conventional applications, including radar and sensing, microwave heating, medical applications, energy transmission, and space technologies.
These emerging application areas represent new frontiers, each with distinct requirements and value propositions. Consequently, microwave amplifiers are now expected not only to achieve wider bandwidth, higher frequencies, higher efficiency, miniaturization, and improved reliability, but also to be optimally designed for specific applications.
At the same time, multiphysics simulation technologies-capable of analyzing device operation under conditions where electromagnetic fields, circuits, and thermal phenomena interact-have become increasingly important in high-frequency design. In particular, methods that integrate thermal analysis with electromagnetic and circuit simulations are now essential for developing high-frequency power devices and power applications.
This workshop provides an overview of practical use cases in these emerging fields, highlights technology trends in key areas such as microwave heating, and introduces state-of-the-art multiphysics simulation techniques, including coupled electromagnetic-thermal analysis and circuit analysis incorporating device heating effects. Through these discussions, the workshop will explore the expanding application landscape of microwave amplifiers and the evolution of design technologies, ultimately presenting a perspective on the "New Frontiers Opened by Microwave Power Amplifiers."

Keyword ： Amplifier, Microwave Heating, Diamond

Research and development of space communication systems using microsatellites are progressing toward the realization of low Earth orbit satellite constellations. In recent years, there has been growing expectation for direct-to-direct (D2D) communication to mobile terminals for disaster relief and coverage area expansion, as well as for wide-area space communication networks that envision communication with aircraft, automobiles, and other vehicles.
This session will outline the operational concept and distributed control technology for a formation flight of more than 10,000 microsatellites using a record-like orbit, and will introduce multi-beam phased array antenna technology in space that supports D2D communication. Furthermore, it will introduce inter-satellite communication systems for microsatellites and provide an outlook on the latest trends in elemental technologies that will support future space communication networks.

Keyword ： Microsatellites, LEO Constellations, Formation Flight Technology, Flight Control Technology, Phased Array Antennas, Inter-satellite Communications

As the Internet of Things (IoT) continues to evolve, technologies that facilitate wide-area, large-scale sensing and monitoring are becoming increasingly crucial in challenging environments, such as the sea, mountainous areas, underground settings, and underwater locations, as well as high-density environments where a large number of devices are connected simultaneously. Specifically, there is an increasing demand for the implementation of satellite communications, communication protocols that facilitate stable wireless connections and support a multitude of devices, and optimization techniques for the effective utilization of limited communication resources. These technologies are identified as essential for the development of next-generation IoT systems.
The workshop will focus on the latest trends in foundational technologies supporting wide-area and high-density IoT in challenging environments, including satellite IoT systems, communication protocols for large-scale IoT, and wireless communication optimization technologies.

Keyword ： Massive IoT, Satellite IoT, Asynchronous Pulse Code Multiple Access (APCMA), Wireless Communication Optimization

Flexible Waveguides (FWGs) for millimeter-wave bands are gaining attention as a transmission technology capable of creating new value across a wide range of industrial fields.
This session will provide an overview of the basic principles, fundamental characteristics, and recent developments of FWG technology, followed by essential evaluation methods, application examples in millimeter-wave communication equipment, and implementations in cryogenic quantum measurement. In addition, emerging applications in measurement instruments, radar systems, and medical devices will be highlighted, presenting the broad potential of FWG technology.

Keyword ： Flexible Waveguides (FWGs), Millimeter-Wave Transmission Technology, Terahertz-Wave Transmission Technology, Transmission loss, Millimeter-Wave Communication Equipment, Waveguide Connectors, Improved Convenience of Millimeter Waves, Medical Device Applications, Cryogenic Quantum Measurement, Measuring Instrument Applications

Photonic crystals and metamaterials, which manipulate light and waves through engineered microstructures, have traditionally advanced by focusing on the precise design of their spatial geometry, enabling diverse forms of wave propagation control. Recently, the notion of structure has been broadening in two directions. The first focuses on topology, that is, how the parts of a shape are connected. In topological photonics, the robustness guaranteed by topology enables stable wave propagation even in the presence of disorder and sharp bends. The second extends structure into the time domain. Dynamic reconfiguration enables functional switching such as the beam steering required in communications. Furthermore, when the structure changes during wave propagation, time-varying phenomena unattainable in conventional systems arise, including highly efficient frequency conversion.
In this workshop, addressing metamaterials in the broad sense, including spacetime structures, we explore new phenomena and applications opened up by this expanding concept of structure.

Keyword ： Topological Photonics, Dynamic Metamaterials, Time-Varying Metamaterials, Fluid Metamaterials, Beam Steering, Frequency Conversion

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Quantum technologies have advanced rapidly in recent years, and microwave techniques play a critical role in their research and development. In solid-state qubits, microwave signals and electromagnetic design are essential for quantum state control, readout, and inter-qubit coupling. As a result, quantum computing has strong connections with conventional RF and microwave engineering.
This session focuses on understanding solid-state qubits from the perspective of microwave circuit design. Representative platforms such as superconducting qubits, silicon spin qubits, and diamond spin qubits will be introduced, and leading researchers in these fields will provide accessible explanations of qubit fundamentals and related technologies. The session aims to clarify both the similarities and differences between these emerging technologies and conventional high-frequency circuit design, deepen understanding of the requirements that quantum technologies place on microwave engineering, and encourage microwave engineers to enter the field of quantum computing.

Keyword ： Solid-state Qubits, Microwave Qubit Control, Quantum Device Design