https://scholar.dgist.ac.kr/handle/20.500.11750/46316 2026-04-04T16:07:14Z 2026-04-04T16:07:14Z Park, Minsu Yoon, Jong-Hyeok Song, Minyoung https://scholar.dgist.ac.kr/handle/20.500.11750/58567 2026-02-05T13:10:18Z 2025-12-31T15:00:00Z

Title: Design and Analysis of ΔΣ Modulator Analogous Bang-Bang Digital PLL Author(s): Park, Minsu; Yoon, Jong-Hyeok; Song, Minyoung Abstract: This paper presents the analysis and design methodology of a second-order ΔΣ modulator analogous bang-bang digital phase-locked loop (DSBPLL). When the bang-bang-based digital PLL (BB-DPLL) cannot fully track the DCO jitter, the jitter slewing effect exacerbates the in-band noise. The proposed DSBPLL can increase the PLL filter order without using a high-order loop filter, thereby mitigating the in-band noise caused by input tracking jitter. Theoretical noise analysis confirmed that the proposed DSBPLL can reduce 54.3% of the integrated jitter from 100 kHz to 100 MHz, consistent with the measurement results.

2025-12-31T15:00:00Z Sufian, Md Abu Lee, Sang-Min Choi, Domin Lee, Jaemin Sim, Dongkyu Song, Minyoung Kim, Nam https://scholar.dgist.ac.kr/handle/20.500.11750/58396 2025-12-18T18:01:11Z 2025-03-31T15:00:00Z

Title: A shared aperture multiport antenna for rural wireless communication and safety monitoring using TVWS, ISM, and 5G mmWave bands Author(s): Sufian, Md Abu; Lee, Sang-Min; Choi, Domin; Lee, Jaemin; Sim, Dongkyu; Song, Minyoung; Kim, Nam Abstract: To accommodate the antenna demand for rural communication and safety monitoring a shared aperture muti-port antenna sensor is presented for three different operating frequencies covering both Sub- 6 GHz and 5G millimeter-wave bands. The antenna sensor is designed on a single substrate, while different ports are connected to different radiating elements to achieve multiple frequency responses. The simulated and measured findings show that the presented antenna can cover TV-white-space (TVWS) frequency band, 5.8 GHz ISM band, and the 5G millimeter-wave frequency band. At the TVWS band, the antenna yields an omnidirectional radiation pattern with a peak gain of 3.14 dBi. While the antenna provides a unidirectional radiation pattern at the 5.8 GHz ISM and 5G millimeter-wave band with a peak gain of 6.76 dBi and 7.68 dBi, respectively. Moreover, all the antenna ports offer a radiation efficiency of more than 92%. Additionally, the 2-port MIMO configuration at the 5G millimeter-wave band shows excellent MIMO diversity performances by utilizing the proposed novel decoupling structure, which consists of metallic stub and cavity vias. Overall performance of the proposed antenna, especially the three operating frequency band including the TVWS band, makes it a viable solution for the sensing and communication in rural areas. © The Author(s) 2025.

2025-03-31T15:00:00Z Lee, Jee Woong Lee, Junhee Lee, Jungha Kim, Duhee Hong, Woongki Lee, Junghyup Song, Minyoung Kang, Hongki https://scholar.dgist.ac.kr/handle/20.500.11750/58214 2025-07-25T02:45:53Z 2025-06-30T15:00:00Z

Title: Transparent Temperature Sensors for Photothermal Neuromodulation: Advances, Challenges, and Future Directions Author(s): Lee, Jee Woong; Lee, Junhee; Lee, Jungha; Kim, Duhee; Hong, Woongki; Lee, Junghyup; Song, Minyoung; Kang, Hongki Abstract: Photothermal neuromodulation, a rapidly advancing technique in neuroscience, has been introduced as an incredibly versatile platform for the in-depth study of neural electrophysiological signals and the development of treatments for various neurological disorders. Particularly, nanomaterial-based photothermal neuromodulation technologies have advantages compared to optogenetic stimulation methods, such as non-genetic modification, minimally invasive, and reduced immune response. Photothermal neuromodulation research has introduced various nanomaterials and stimulation methods to regulate thermosensitive ion channels or modify cell membrane capacitance, enabling excitation and inhibition of neural activity. Recent advances in nanomaterials have significantly improved the precision and efficiency of photothermal neuromodulation, expanding its potential applications in neuroscience research. In the photothermal neuromodulation studies, different temperature measurement methods have been used but do not satisfy all the requirements necessary to analyze this phenomenon. An ideal temperature sensor for a photothermal neuromodulation study must have high transparency, high thermal sensitivity, and high spatial and temporal resolution. This review aims to cover the current status of thermally induced neuromodulation studies and the transparent temperature sensing methodologies that can be used for photothermal neuromodulation.

2025-06-30T15:00:00Z Kim, Chanyoung Lee, Junghyup Song, Minyoung https://scholar.dgist.ac.kr/handle/20.500.11750/57679 2025-07-25T03:34:32Z 2024-11-30T15:00:00Z

Title: Wireless System Miniaturization Solutions for Ingestible Sensors Author(s): Kim, Chanyoung; Lee, Junghyup; Song, Minyoung Abstract: Ingestible sensors are pivotal in monitoring the gastrointestinal (GI) tract and enhancing comprehension of complex gastrointestinal processes, propelled by sensor technology advancements. They must ensure robust wireless communication from deep within the body while maintaining longevity for comprehensive monitoring. Wireless system miniaturization stands as a promising solution to these challenges. This paper introduces the current state and technical challenges ingestible sensors and their solutions for wireless system miniaturization. The key techniques for further miniaturization include the antenna miniaturization, integration of adaptive impedance matching networks, and the replacement of crystal. Additionally, the paper explores future directions for wireless communication systems to support the continued advancement of ingestible sensor technology.

2024-11-30T15:00:00Z