使用時域有限差分法分析共平面波導之不連續面的特性

Abstract

本論文使用時域有限差分法分析一些共平面波導不連續面的特性.首先分 析開路和短路及裂隙不連續面. 把模擬與實驗結果作比較時,發現兩者是 吻合的. 此外開路及短路不連續面的實驗原理和方法在本論文□有很詳細 的說明. 接下來分析三種以不同型式作九十度轉彎的共平面波導的特性. 為了配合量測夾具, 作者製作有兩個九十度轉彎的共平面波導來實際量 測. 模擬結果將以 ABCD 參數把有兩個轉彎的效應結合在一起, 最後量測 結果就可直接和模擬結果比較;並且結論出較好的九十度轉彎型式. Several coplanar waveguide (CPW) discontinuities are characterized using the finite-difference time-domain (FDTD) method. The normalized equivalent inductance and capacitance of the CPW open-end and short-end is calculated first. The measured data is given for comparision and it is in good agreement with the simulated result. The detail of measurement method is also described. And then CPW gap is calculated. Comparision with the measured data from published paper and the calculated one is also in good agreement. Based on the flexibility of the FDTD method for typical circuit, author extends the method to calculate the CPW bend with different miter. Using the transformation of ABCD-parameters, author combines the effect of two bends and some transmission line to a two-port probelms of a larger circuit. After such transformation, the two-bend structure can be measured on the test fixture which is available. Comparision between simulated results of three different-mitered is given. And the better bend structure is suggested.