Development of Microwave Interferometry System for Magnetized Plasma Diagnostics

• Main Authors: Syu-JheWang, 王勗哲
• Other Authors: Chio-Zong Cheng
• Format: Others
• Language: en_US
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/88004724440680857027

碩士 === 國立成功大學 === 太空天文與電漿科學研究所 === 99 === In the thesis, we develop a microwave interferometer system to measure the line-integrated plasma density. At first, we discuss the EM wave propagation in magnetized plasmas by using the plasma wave theory. The EM wave dispersion relation depends on the direction of the wave electric field with respect to the external magnetic field. We can use the dispersion relation to obtain the relation between the phase delay of the probe wave and the line-integrated plasma density. The interferometry system measures the phase delay and is a non-contact instrument for the plasma density measurement in magnetized plasmas. The EM wave is divided into two paths: the probe wave passes through the plasma and the other wave serves as the reference signal. We use mixers to combine the two signals and obtain the phase difference to calculate the plasma line-integrated density. The plasma line-integrated density is on the order of 1015?1017 m-2 in the magnetic mirror plasma device at the Plasma and Space Science Center (PSSC) at the National Cheng Kung University (NCKU). Finally, we discuss what can be improved in the future.