3-D 低溫共燒陶瓷與共平面波導饋入雙模環形濾波器

Abstract

In the beginning of this thesis, I mention the basic theory and characteristics of ring resonators. Afterwards, I make use of the advantage of LTCC process to realize the 3-D coupling structure and to design dual-mode ring filters. Here, I base on different design specifications to design two broadband and two narrowband ring filters. The narrowband filters have the fractional bandwidth less than 15%. The wideband filters have the fractional bandwidth larger than 25%. In addition, I make use of the CPW-fed microstrip method to implement the 3-Dcoupling structure in the single substrate. With this approach, the uniplanar circuit design implemented in single substrate can be extended to 3-D design. Thus, the 3D ring filters become possible. Since the embedded microstrip lines used in the LTCC ring filters and the microstrip lines used in the CPW-fed microstrip ring filters possess serious dispersion phenomenon and radiation loss. One can use strip lines to avoid these disadvantages. Therefore, I further use the method of CPW-fed strip lines to realize the 3D coupling structure to modify the ring filters. Observed form the measurement, the insertion loss of this kind filter can be greatly improved (Insertion Loss < 1dB).