臺灣博碩士論文加值系統

本文提出一種新的屋頂型梯形基底，並以動差法在頻域中分析各種不同的微帶轉角特性。在微帶轉角結構中，任意形狀上的電流將以屋頂型基底展開，且在全波分析中，以動差法求出電流分布，進而由矩陣方程中求得S 參數。為驗證梯形基底，分別將二種不同的微帶天線，以方形及梯形切割來加以佐證。在本文中，將探討微帶直角、斜接轉角與圓弧轉角的特性。微帶直角轉角容易在轉角處產生高模態，而斜接轉角與圓弧轉角結構可以改善這個不理想的效應。

In this study, microstrip bend discontinuities are investigated by using the full-wave spectral-domin approach based on the Galerkin's moment method. The new rooftop trapezoid basis functions are proposed and used to expand the currents on arbitrarily shaped discontinuities structures. These currents are then solved by the full-wave analysis usng the Galerkin's weighting procedure, and the S-parameters are extracted from the matrix equation.
For validation, the proposed trapezoid basis functions are employed to handle the microstrip patch and dipole antennas which are also analyzed by the rectangular basis functions.
The corner ( right angle ) bends show poor responses in reflection and power losses which can be improved by the use of miter or round bend structures. In this study, the bend structures such as microstrip corner and round bends are investigated.

1 Introstruction
2 spectral Domain Analysis
3 Basis Functions
4 Microstrip Bend Discontinuities
5 Conclusion

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