Chi Hou Chan of City University of Hong Kong

The hope for wireless communications to reach capacity equality with fiber optics by expanding the operating frequency band into terahertz (THz) could not be realized without high-gain antennas along with high-power sources.  For THz antenna design, the feeding mechanism has to be compatible with the testing equipment in which only waveguide ports are available.The conventional probe feed at microwave and popular substrate-integrated-waveguide feed at millimeter-wave frequencies would not be viable at THz due to the required high precision and large material loss, respectively. Dielectric materials to be used for the antennas need to be electrically characterized for their dielectric constant and loss tangent at THz frequencies. Depending on the operating frequency and antenna type, fabrication process of the design varies from 3D printing, printed-circuit-board (PCB) and micromachining technology. For example, lens antennas up to 0.3 THz can be fabricated by 3D printing. Similarly, reflectarrays and transmitarrays up to 0.3 THz can be fabricated by PCB process. However, beyond 0.3 THz, we need to resort to micromachining. For high-gain antennas, far-field radiation pattern measurement may be hindered by the dynamic range of the testing equipment. We then make use of our purpose-built near-field measurement system when the occasion arises. In this keynote, we will present our THz antenna designs in the past few years together with their fabrication processes and measurement approaches and results.

Biography:

Professor Chi Hou Chan received the B.S. and M.S. degrees in electrical engineering from the Ohio State University, Columbus, OH, USA, in 1981 and 1982, respectively, and the Ph.D. degree in electrical engineering from the University of Illinois, Urbana, IL, USA, in 1987. From 1987 to 1989, Dr. Chan was a Visiting Assistant Professor in the Department of Electrical and Computer Engineering at the University of Illinois. He joined the Department of Electrical Engineering at the University of Washington, Seattle, USA as an Assistant Professor in 1989 and was promoted to Associate Professor with tenure in 1993. In 1996, he joined the Department of Electronic Engineering, City University of Hong Kong as a Professor, and was promoted to Chair Professor of Electronic Engineering in 1998. From 1998 to 2009, he was first Associate Dean and then Dean of College of Science and Engineering. He also served as Acting Provost of the university from July 2009 to September 2010. He is currently the Director of State Key Laboratory of Millimeter Waves, Partner Laboratory in the City University of Hong Kong.  His current research interests include computational electromagnetics, millimeter-wave circuits and antennas, and terahertz science and technology. Dr. Chan received the U.S. National Science Foundation Presidential Young Investigator Award in 1991 and the Joint Research Fund for Hong Kong and Macao Young Scholars, National Science Fund for Distinguished Young Scholars, China, in 2004. He received outstanding teacher awards from the Department of Electronic Engineering, CityU in 1998, 1999, 2000, and 2006.  He is the General Co-Chair of ISAP 2010, iWAT2011, iWEN 2013, ICCEM 2015, ICCEM 2016, GSMM2017, and ICCEM 2018.

Sheng-Cai Shi of Key Lab of Radio Astronomy, CAS

Dome A in Antarctic – the site for China’s Antarctic Observatory, may offer the best possible access for ground-based astronomical observations in the THz and FIR band. We recently carried out measurements of atmospheric radiation from Dome A spanning the entire water vapor pure rotation band from 20 μm to 350 μm wavelength (0.75~15 THz) by an unmanned Fourier transform spectrometer (FTS). Our measurements expose atmospheric windows having significant transmission throughout this band. This talk will firstly introduce our FTS measurement results from Dome A, and then the latest development of superconducting mixers and detectors for the DATE5 telescope proposed to build at China’s Antarctic

Biography:

He received his B.S. degree from Southeast University, China, in 1985 in radio engineering, M.S. degree from Graduate School of Chinese Academy of Sciences (CAS), China, in 1988 in astronomical instrumentation, Ph.D. degree in radio astronomy from the Graduate University for Advanced Studies, Japan, in 1996. From 1992 to 1998, he was with Nobeyama Radio Observatory (NRO), National Astronomical Observatory of Japan as a NRO and COE researcher, focusing on research on superconducting tunnel junction mixers. He has been a Professor and the Head of Mm- & Submm-Wave Lab at PMO since 1998. He is currently serving as the Chair of the Key Lab of Radio Astronomy of CAS. His current research interests include physics of superconducting devices, THz mixers and detectors, and THz applications. He has authored and co-authored over 200 scientific publications.

Email:

Address:Nanjing, Jiangsu, China