盧信嘉臺灣大學：電子工程學研究所張喬傑Chang, Chiao-chiehChiao-chiehChang2007-11-272018-07-102007-11-272018-07-102006http://ntur.lib.ntu.edu.tw//handle/246246/57681在本論文提出應用於雙頻無線區域網路頻段差動傳送/接收切換開關之設計。假若在電路中使用平衡式架構，則可省去baluns，並且對於平衡式架構具有使用虛擬接地以改善較差的實際接地，並降低共模雜訊干擾等優點。此外，本論文所提出之電路架構具有在接收時不消耗功率之特性，特別適用於無線通訊的相關應用。 　　在設計新的傳送接收開關中，採用LTCC (low-temperature co-fired ceramics)的製程，可相較於一般如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。本論文並提出基於此架構兩個分別操作於2.4GHz及5.2GHz的開關及其量測結果。In this thesis, we present a new architecture of differential T/R switches for wireless local-area network (WLAN). If we use the balanced-type circuit, the number of the devices, such as a balun, can be reduced. The balanced circuit can also improve the poor ground and suppress the common-mode interference. In addiction, the proposed architecture consumes no DC power at the receiving mode, which is especially suitable for portable wireless applications. The LTCC (low temperature co-fired ceramic) is chosen for its low loss and multi-layer structure, which will give better insertion loss and give more freedom in balanced-type device design. The design procedure and measurement results of two differential switches operating at 2.4GHz and 5.2GHz are presented in this thesis.Chapter 1 Introduction 1 1.1 Motivation 1 1.2 Overview of the RF T/R switches 2 1.3 RF System on Package (SoP) for wireless communications 5 1.3.1 Advantages of RF-SOP 7 1.4 Introduction of LTCC 7 1.4.1 Fabrication process 8 1.4.2 Material used 9 1.4.3 Advantages of LTCC 9 1.4.3.1 Cost reduction 10 1.4.3.2 Reduction in size 11 1.4.3.3 Low loss at microwave frequency 11 1.4.3.4 Stable dielectric constant with respect to frequency 11 1.5 Organization of thesis 12 Chapter 2 RF T/R switch 13 2.1 Introduction 13 2.2 Switching devices 14 2.2.1 MESFET 14 2.2.2 MOSFET 16 2.2.3 PIN diodes 17 2.2.3.1 PIN diode fundamentals 17 2.2.3.2 Forward biased PIN diodes 18 2.2.3.3 Reverse biased PIN diodes 20 2.2.4 Comparison of switching devices 21 2.3 PIN diode T/R switch topologies 23 2.3.1 Single-pole single-throw (SPST) switches 23 2.3.2 Single-pole double-throw (SPDT) switches 25 2.3.2.1 SPDT with series connected PIN diodes 25 2.3.2.2 SPDT with transmission line 27 2.3.2.3 SPDT with a combination of a series and a shunt connected diode 29 Chapter 3 Differential T/R switches 32 3.1 Wireless local area network systems 32 3.2 The design of differential T/R switches 34 3.2.1 From single-ended to dual single-ended switch 34 3.2.2 From dual single-ended to differential switch 36 3.2.3 Board level test design of a differential T/R switch at 2.4GHz 39 3.2.3.1 Bandstop filters for RF chokes 40 3.2.3.2 Coupled microstrip lines 42 3.2.3.3 Simulation results of whole differential switch 44 3.3 Differential T/R switches with transmission line in LTCC, the version I.47 3.3.1 transmission lines in LTCC process 48 3.3.2 Simulation results of the version II switches 51 3.4 Differential T/R switches with lumped-element implemented transmission line in LTCC, the version II 57 3.4.1 Lumped-element implemented transmission lines 58 3.4.2 Matching network 60 3.4.3 Simulation results of the version II switches 61 Chapter 4 Measurement procedures and results 69 4.1 Introduction 69 4.2 Insertion loss test for baluns 69 4.3 Measurement results of board level test design of a differential T/R switch for 2.45GHz 71 4.4 Measurement results of the version I differential T/R switches in LTCC 77 4.5 Performance Comparison 86 Chapter 5 Conclusion 88 Reference 892900004 bytesapplication/pdfen-US低溫共燒陶瓷802.11差動發射/接收切換開關LTCCdifferential T/R switchthesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/57681/1/ntu-95-R92943080-1.pdf