我們利用天線轉換方法，開發出量測磁化電漿密度分佈之微波診測儀器-「多通道微波干涉儀(Multichannel Interferometer with Antenna Switching System, MIASS)」。多通道微波干涉儀系統具有獨特的設計，使用 <1> 一個單刀雙擲(Single-Pole Double-Throw, SPDT)切換器; <2>兩個單刀六擲(Single-Pole 6-Throw, SP6T)開關; <3> 12個縫隙天線，而不是喇叭天線; <4>外差干涉儀系統的兩個自由運行的振盪器。使用天線轉換技術，發展新的多通道干涉儀的主要動機是為了開發一個穩定並具有低成本高效益的多通道干涉儀系統，以量測磁化電漿的電子密度徑向(radial)分佈。
在以磁場控制電漿之核融合研究中，量測電漿密度分佈是非常重要的。我們使用MIASS，在國立成功大學電漿與太空科學中心的磁化電漿裝置(MPX, Magnetized Plasma eXperiment) 之實驗中，量測12個微波通道之線平均電子密度(line-averaged electron density)。並發展一阿貝爾逆轉換(Abel Inversion)程式，成功將12個微波通道之線平均電子密度轉換為電子密度的徑向分佈。

We have developed a new type of multichannel interferometer with the use of antenna-switching method for measuring the electron density profile of magnetized plasmas. The Multichannel Interferometer with Antenna Switching System (MIASS) has a unique design by using (1) one Single-Pole Double-Throw (SPDT) switch; (2) two Single-Pole 6-Throw (SP6T) switches; and (3) twelve tapered slot antennas instead of horn antennas. Here, the interferometer is a heterodyne system employing two free-running oscillators. The main motivation for the new multichannel interferometer using antenna switching is to achieve a stable and cost effective multichannel interferometer for measuring the radial electron density profile in the magnetized plasma experiment.
It is necessary to measurement the plasma density distribution in order to study the improvement of plasma confinement for fusion plasma experiments. The plasma density profile in the experiments using the MPX (Magnetized Plasma eXperiment) device at Plasma and Space Science Center, National Cheng Kung University has been successfully measured by using the 12 channel MIASS. The radial electron density profile is obtained by using an Abel inversion code which we developed to calculate the radial electron density profile from the data of 12 channel line-averaged density measurements.

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