X頻段金屬氧化物半導體主動雙模環形諧振器帶止濾波器

Abstract

這篇論文的主題是分析及設計以環型諧振器為主要諧振器的雙模濾波器。本篇論文中的濾波器皆設計在X頻段內，並且使用0.13微米製程的金屬氧化物半導體技術進行設計。本論文提出的架構，是以一種合成準橫向電磁波模互補式金屬微帶線作為傳輸線結構構成一環型諧振器，並使用指叉式電容對諧振器進行微擾。同時為補償傳輸線阻抗，兩組交錯耦合對被互相垂直地放置於諧振器中以分別補償在雙模諧振器中的兩個模態。本設計使用高度彎曲的傳輸線並以主動電路補償其傳輸能量的損失，所以本文中的濾波器面積非常的小，只有750微米見方。此外，由於主動電路補償了傳輸線的損耗，使得諧振器的Q值非常的高，因此本設計在阻止帶中擁有很小的反射損失，且有不錯的帶阻效果，加上阻止帶的邊緣非常的陡峭，因此濾波器擁有很高的訊號選擇性。在本論文中，提出三個帶阻濾波器的設計，且三個濾波器的面積均相同。第一個設計擁有非常窄的阻止帶(比例頻寬約為1%)，且有非常陡峭的頻帶響應。第二個設計為寬頻的雙模帶阻濾波器，頻寬比較寬(比例頻寬約5%)，阻止帶內也有很小的反射損失及不錯的帶阻效果。第三個設計為雙頻帶的雙模帶阻濾波器。兩個頻帶分別設計在7GHz到7.5GHz以及10GHz到10.5GHz，在910微米見方的面積中，實現兩個具有主動補償的雙模諧振器，達到擁有陡峭邊緣的通帶以及具有小的阻止帶反射損失。在這邊論文中，分別討論有關於不同微擾對於雙模分離的影響及耦合線對於雙模的影響。此外，論文中也討論了雙頻濾波器可能會遇到的問題，並嘗試使用垂直的堆疊結構，以及非對稱或者多條的耦合線。最後，本論文提出模擬和實際實驗的結果，作為驗證。

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.