Tutorial Title: Dielectric properties determination using free space technique
Dielectric material has unique dielectric properties that are important to many applications. A number of dielectric characterization techniques at microwave frequencies have been developed. The resonant method using the cavity perturbation technique is suited to low dielectric loss material. The accuracy is limited by the cavity size. For non-resonant method, the transmission line technique needs an adequate sample thickness to obtain an accurate result. An open-ended probe technique can measure over a wide frequency range with moderate accuracy needs a sufficiently thick material sample with the flat contact surface of the probe and there is not any air gap. The free space technique measures attenuation in amplitude and phase shift of the signal from a sample placed between a transmitting antenna and a receiving antenna. This method is non-contacting and can be applied to materials under test with high temperature and hostile environments. This tutorial will review the dielectric characterization techniques and address the principle of the free space technique.
King Mongkut’s Institute of Technology Ladkrabang Bangkok 10520, Thailand
He was a visiting research scholar at Tokai University in 1988 and at Yokosuka Radio Communications Research Center, Communications Research Laboratory (CRL) in 2004. He joined the KMITL and is currently a Professor at the Department of Telecommunication Engineering. He has served as the Director of the Research Center for Communications and Information Technology during 1997-2002. His main research interests are in antennas for mobile communications and microwave in agricultural applications. He was the chairman of the IEEE MTT/AP/Ed joint chapter in2005 and 2006. He served as the General Chairman of the 2007 Asia Pacific Microwave Conference, and the advisory committee of the 2009 International Symposium on Antennas and Propagation. He was the President of the Electrical Engineering/ Electronics, Computer, Telecommunications and Information Technology Association (ECTI) in 2010 and 2011 and was an editor-in-chief of the ECTI Transactions on Electrical Engineering, Electronics, and Communications. He was recognized as a Senior Research Scholar of the Thailand Research Fund in 2005 and 2008 and a Distinguished Research Scholar of the National Research Council of Thailand. He has been a distinguished lecturer of IEEE Antennas and Propagation Society during 2012-2014.