本實驗標的是用穿透反射法(TR Method)測量裝載於WR-90波導中的鐵氧體(ferrite)在8.2GHz~12.4GHz頻段的介電系數 、飽和磁化量 跟線寬 ，並可以由 及線 此得知其磁導張量(permeability tensor)。跟用充磁方式測量磁滯曲線及飽和磁化量不同，此方法可以同時量測出 、 跟 ，並且微波量測可以確認其 於各頻段的反應，然而相較於同樣屬於微波量測的共振腔法，此方法比較適合量測較高吸收的材料並且有較廣的量測頻寬。
實驗的數據分析是根據模式分析(Modal Analysis)的理論計算來，而實驗方法為網路分析儀量測在一已知的外加直流磁場偏壓下，其穿透及反射在外加磁場下的變化及共振頻偏移，再用此測得數據做理論計算求出材料的 、 及 ，由此也可以算出磁導張量(permeability tensor)。
在本論文中會詳細的介紹實驗步驟，並記錄實作中要注意的問題，從樣品準備及波導製作、組裝、系統架設到量測；也會介紹數據分析方法的理論基礎，即從在此實驗條件下的模式分析開始及數據分析的演算方法到最後的HFSS反算檢查驗證；最後就是本實驗的結論以及依我目前的認知提供以後要將其完善的話可以嘗試的參考做法。

Characterizing the complex permeability and permittivity provide useful clues to unveil the intriguing mechanism of microwave-material interaction. The main purpose of this work is to measure the permeability tensors (magnetic saturation & linewidth ) and permittivity of ferrites. The ferrites are fully embedded in WR-90 waveguide with frequency ranging from 8.2 to 12.4 GHz under a static magnetic field. The transmission/reflection (TR) method is employed, which has broader bandwidth and is more suitable to lossy materials as comparing with the resonant cavity system.
By measuring the S-Matrix of ferrite under a controlled dc magnetic bias, the transmission and reflection peaks shift due to the change of the permeability tensor. The experimental data and the theoretical calculation based on modal analysis, jointly give us the magnetic saturation , linewidth , or the permeability tensor as well and permittivity .

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