[Abstract] With the rapid advancement of wireless communication technology, the demand for low-profile antennas with wide bandwidth has intensified. This trend is driven by the need for components that can be seamlessly integrated into diverse devices, cover extensive frequency ranges, and ensure reliable long-distance signal transmission with low power consumption. Dipole antennas are extensively utilized in wireless systems due to their simple design and ease of fabrication, making them ideal for mass production. While their basic structure offers significant design flexibility, conventional dipoles often suffer from limited bandwidth. By adopting a wide-width arm geometry, a dipole antenna can achieve a lower characteristic impedance and support multiple resonances. To overcome the typical limitation of widely spaced resonant modes in such designs, a mode-compression technique is employed—utilizing strategic stub loading or slotting—to shift higher-order resonances toward the fundamental mode. This alignment results in a significantly broadened impedance bandwidth and stable radiation patterns across multiple frequency bands. This compact, planar design offers a robust solution for modern high-speed data transmission, where wideband performance and a low profile are critical. This paper presents the development of a mode-compressed wide-width dipole antenna tailored for versatile wireless communication applications.

[Abstract] TBA

[Abstract] The Internet of Things (IoT) technology enables the integration of diverse sensors to digitize physical data, supporting rapid processing and timely responses in a smart society. Among these, electromagnetic (EM) sensors offer a low-cost, versatile and scalable approach for material sensing, based on the interaction between electric fields and dielectric materials. Electromagnetic properties of materials are sensitive to compositional variations, enabling the detection of changes in samples for applications in environmental monitoring, biomedical diagnostics, and agriculture. EM sensors can be designed to detect specific parameters, such as the concentration of chemical or biological substances in mixtures. To optimize sensitivity, material samples are characterized using standard laboratory techniques, e.g. dielectric probe measurements. Their frequency-dependent behavior then guides the selection of an operating frequency that maximizes sensitivity, enabling the design of tailor-made sensors for targeted detection. Beyond sensing, material characterization also plays a fundamental role in the design and optimization of RF systems, particularly as emerging applications demand materials with tailored electromagnetic properties. Besides, the rapid growth of modern electronic devices has intensified the challenge of electronic waste, thereby motivating research into environmentally friendly dielectric substrates and alternative conductive materials such as MXenes, graphene, and indium tin oxide (ITO). Combined with emerging fabrication techniques e.g. 3D printing and laser-based processes, these materials enable rapid, cost-effective prototyping of RF components. Close collaboration between antenna engineers and material scientists further allows the co-design of materials and devices, where material characterization serves both as a design foundation and as a feedback mechanism for material innovation.

[Abstract] Lightweight, high-gain, and beam-scanning capabilities are essential requirements for antenna structures in next-generation communication systems. Transmitarray (TA) antennas represent a promising solution due to their low-profile, lightweight, and cost-effective characteristics. A transmitarray consists of an array of unit cells designed to provide appropriate transmission phase shifts, enabling the collimation of incident waves into a desired direction. Ultra-thin unit cells offer significant advantages from both electromagnetic and system integration perspectives. Their reduced thickness enables an even lower-profile and lighter structure. Moreover, ultra-thin transmitarrays exhibit enhanced mechanical flexibility, allowing them to be bent and conformed to curved surfaces. This makes them highly attractive for conformal antenna applications, especially for integration onto UAV platforms. In this work, a method is proposed to design ultra-thin unit cells that maximize phase range while preserving high transmission efficiency. These features demonstrate the strong potential of ultra-thin transmitarrays for high-performance conformal antenna systems in modern communication applications.