盧信嘉　臺灣大學：電子工程學研究所蔡昆宏Tsai, Kun-HungKun-HungTsai2007-11-272018-07-102007-11-272018-07-102005http://ntur.lib.ntu.edu.tw//handle/246246/57447在本論文提出應用於雙頻無線區域網路頻段差動帶通濾波器和差動雙工器之設計。假若在電路中使用平衡式架構，則可省去balun，且平衡式架構具有使用虛擬接地以改善較差的實際接地，並降低同模雜訊干擾等優點。差動帶通濾波器設計中，再加上兩個零點，可改善帶通濾波器的效能，另外在差動雙工器設計中，加入LC共振器，對於雙工器的兩個頻帶(2.4GHz和5.2GHz)可提供良好的隔離。 　　在設計新的帶通濾波器和雙工器中，採用LTCC (low-temperature co-fired ceramics)的製程，相較於一般如FR4的板材,此基材在微波頻具有較低之正切損失，並具有多層結構有利於平衡式傳輸線的設計。In the paper, we present a new balanced filter and a balanced diplexer for dual-band wireless local-area network (WLAN). By using the balanced-type circuit, balun can be eliminated. The balanced circuit can also improve the poor ground and suppress the common-mode interference. In addition, this filter which uses two finite transmission zeros can improve the filter rolloff rate near passband and the diplexer which uses LC resonator can obtain better isolation. The LTCC (low temperature co-fired ceramic) is chosen for our component implementation for its low loss and multi-layer structure, which will give better insertion loss and give more freedom in balanced-type device design.Abstract Table of Contents List of Figures List of Tables Chapter 1 Introduction 1 1.1 Motivation 1 1.2 Filters in wireless system 2 1.3 Low temperature co-fired ceramics (LTCC) 5 1.4 Overview 8 Chapter 2 Filters 11 2.1 Introduction 11 2.2 Filter type and frequency response 12 2.2 Filter design by the insertion loss method 15 2.3 Lowpass filter 15 2.3.1 Butterworth filter 16 2.3.2 Chebyshev equal-ripple filter 18 2.3.3 Linear phase lowpass filter 19 2.4 Frequency and element transformations in lump element filter 20 2.4.1 Lowpass transformation 21 2.4.2 Lowpass to highpass transformation 22 2.4.3 Bandpass and bandstop transformation 23 2.5 Coupled line filters in distributed type filter 25 2.5.1 Coupled line bandpass filtr 25 2.5.3 Coupled resonator filter 28 2.5.4 Capacitively coupled shunt resonator bandpass filter 30 2.6 Design of bandpass filter with two zeros 31 2.6.1 Combline filter 31 2.6.2 Interdigital bandpass filter with tapped-line 34 2.6.3 Combline bandpass filter with tapped line 37 2.6.4 Combline bandpass filter with two finite transmission zeros and tapped-line input/output 38 Chapter 3 Balanced-input-output filter 41 3.1 Introduction 41 3.2 Balanced-type combline bandpass filter with two finite transmission zeros and tapped-line input/output 42 3.2.1 Design method of bandpass filter for balanced-type configuration 42 3.2.2 Circuit model of balanced bandpass filter 45 3.3 Simulation results 46 Chapter 4 Balanced-input-output diplexer 51 4.1 Introduction 51 4.2 Balanced-type diplexer design procedure 53 4.3 Proposed diplexer and simulation results 55 4.4 Summary 58 Chapter 5 Measurement procedures and results 59 5.1 Introduction 59 5.2 Measurement method of differential two-port devices 60 5.3 TRL calibration method 60 5.4 Measurement considerations for differential diplexer 66 Chapter 6 Conclusion 75 Reference 775321895 bytesapplication/pdfen-US低溫共燒陶瓷製程差動帶通濾波器差動雙工器ltccdifferential filterdifferential diplexerthesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/57447/1/ntu-94-R92943027-1.pdf