微波診測是一種常見的非侵入式電漿診測工具。在本篇論文中,我們運用時域有限差分法模擬電磁波在磁化電漿中傳播,電磁波於磁化電漿內部會受到電漿密度與磁場的不均勻而產生色散,並有不同的傳播特性。本模型是由Maxwell equations,再加上電流密度在cold magnetized plasma中響應之方程式所架構的.此模型可以模擬微波在Ordinary mode和Extraordinary mode 中傳播及反射。在干涉計模型中,我們運用微波干涉計原理測量相位變化，進而得到電漿平均密度。在反射計模型中,我們採用超短脈衝行進於Ordinary mode和Extraordinary mode並完成重建電漿密度分佈的問題。重建電漿密度需要知道截止頻率所對應的反射時間,我們採用了三種方法對反射信號進行時頻分析，並比較了其結果。

Microwave diagnostics are relatively common nonintrusive plasma diagnostic tools. In this thesis, we present simulation studies of microwave diagnostics of plasmas by solving the full wave equations by using a finite-difference time-domain method. The simulation model is based on the Maxwell’s equations and the fluid equations of cold magnetized plasmas, which describes the ordinary and extraordinary modes and their propagation in plasmas. We present results of simulations on (1) the interfelometry measurement of the line-integrated plasma density by measuring the phase shift of monochromatic incident waves; (2) reflectometry measurement of plasma density profiles by using of ultra-short pulse probing waves based on O-mode and X-mode propagation. In the reflectometry measurement, we apply three different methods to process the spectral analysis of the phase delay of the reflected signals. The simulation results demonstrate that the determination of plasma density from ultra-short pulse reflectometry is relatively robust.

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