在核融合電漿、工業電漿和太空電漿中，電漿密度量測是電漿實驗當中一個基本需求。我們利用磁化電漿的旋轉及單檢測器之干涉儀建構了一個新的測量方法來測量二維的電漿密度分佈，此種方法被稱為使用多通道天線轉換之傅立葉貝索擴張法。天線轉換是一種使用機電微波開關來暫時切換檢測電路、數據採集通道和多個天線接收器之間連接的技術。傅立葉擴張法是一種將密度分佈在方位角方向用傅立葉系列擴張及在徑向用貝索方程式擴張再使用最小平方法的技術。為了將傅立葉貝索擴張法應用至實驗室磁化電漿中，我們利用了電漿柱繞其軸線的剛性旋轉而非探測器的旋轉。在我們的數值實驗中，在典型的不穩定電漿飄移波極向模式m=13及擾動程度n/n0=0.10.5下，傅立葉貝索擴張法的投影方位角的解析度小於三十度是被需要的來重建非對稱的密度分佈。我們透過實驗證明的MIASS對MPX電漿轉速測量的能力，為此我們使用了Langmuir 探針陣列(LPA)來電漿密度的擾動做為參考。透過MIASS和LPA 測量到的平率-波數譜之間的比較我們可以發現在n/n0=0.1下，我們可以透過MIASS來單獨辨認m=1旋轉的MPX電漿。LPA數據則可用於評估m=2或3結構的電漿旋轉。傅立葉貝索擴張法也透過使用天線轉換微波干涉儀來量測MPX電漿來得到驗證。

Measurement of plasma density profile is a fundamental requirement in plasma experiments, such as fusion plasmas, industrial plasmas, space plasmas, etc. We established a novel measurement method of two-dimensional density profiles of rotating laboratory magnetized plasmas with single-detector microwave interferometry, named Fourier-Bessel expansion method using multichannel antenna switching system (FB expansion with MIASS).The antenna switching system is a technique using electromechanical microwave switches to temporally switch the connection between multiple receiver antennas with single set of a detection circuit, and a data acquisition channel. FB expansion method is a reconstruction method which expands the density profile in Fourier series in azimuthal direction and the Bessel functions in the radial direction with the use of a least-square method. To apply the FB expansion method to laboratory magnetized plasmas, we utilize a rigid rotation of the plasma column about its axis instead of a rotation of the detectors. Our numerical tests of the FB expansion method indicate that smaller azimuthal angle resolution of projection than 40 degrees is required for reconstruction of asymmetric density profiles whose poloidal mode m=13 and the perturbation level n/n0=0.10.5, which are typical profiles of MPX plasmas unstable for drift waves.
Two-dimensional plasma profiles of the MPX plasma were obtained by applying the developed reconstruction technique, the Fourier-Bessel reconstruction with the use of MIASS to the experiment. We confirmed a rigid rotation of the plasma from the measurement of a radial profile of the rotation frequency of the density fluctuation by LPA. The reconstructed density profiles have a structure having m = 1 mode as a dominant mode in addition to m = 2 mode. It is consistent with the result of the 2D power spectra measured by LPA although soundness of the developed technique needs further verification.

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