| Summary: | 碩士 === 國立臺灣大學 === 電信工程學研究所 === 100 === The topic of this thesis is to design and analyze dual-mode ring-resonator-based bandstop filters which are designed to filter out unwanted signals in X band. These filters are fabricated on standard 0.13μm complementary metal oxide semiconductor (CMOS) process. To implement the dual-mode resonator, a type of artificial synthetic quasi-TEM transmission line called complementary conducting strip (CCS) is used to construct a ring resonator with an inter-digital capacitor load on the resonator as a perturbation. In these designs, transmission lines are highly meandered, and the total area of these filters are equal or less than 750μm×750μm or 0.03λ_0×0.03λ_0, which is a very small area. Besides, two cross-coupled pairs are put orthogonally to compensate the losses of two modes in the resonator, respectively. The Q factor of the resonator is very high and therefore these filters can achieve low return loss and good rejection level with a very sharp bandstop response. There are three designs proposed in this thesis. The first one is designed to achieve very narrow bandwidth (1% of fractional bandwidth) and a very steep bandstop response. The second design offers wider stopband bandwidth (4% of fractional bandwidth). The third is a dual-band dual-mode bandstop filter which implemented two resonators in the area of 910μm×910μm, also with narrow bandwidth and sharp response. In this thesis, some issues to design the dual-mode filter are discussed, like the relation between perturbation and mode splitting and the effect of the coupled line. On the other hand, some special strucutures of dual-band dual-mode filter are also discussed, such as the vertical stacked transmission line, multi-metal coupled line and asymmetric coupled line. At last, the simulation and measurement results are shown as well.
|
|---|
