Design of an Extremely Miniaturized Balun Filter Using Open-stubs for Harmonic Suppression

최근，무선 주파수(RF)와 마이크로파는 무선 통신 시스템에서 널리 사용되고 있기 때문에 급속하게 개발되었다.무선 통신 송수신기중에 RF프론트의 특별한 기능은 전 세계 무선 통신 도메인의 연구에서 핵심적인 역할을 하고 있다.RF회로에서 총괄적인 커패시턴스를 결합되여, Diagonally와 Parallel으로 RF기본적인 성분들로 RF회로의 균형 있는 mixers, 전력 증폭기, 안테나 공급 네트워크 과 같은 많은 종류에 사용될 수 있다. 따라서,  RF bandpass 필터시스템 콤팩트화 및 작고 쉽게 구현할 수 있도록 전송 선로의 크기를 줄이고 조화를 이루는 것이 가장 중요하다. 고성능은 우리가 작은 사이즈를 추구할때에 필요로 하다. 균형 잡힌 포트 매칭 포트와 같은 일부 소형 전송 필터에는 애플리케이션이 제한되어 있으므로 애플리케이션을 제한할 수 있다.무선 응용 프로그램에서는 균형 잡힌 구성 요소를 균형 잡힌 구성 요소로 자주 연결하는 Balun 핀을 사용하지만 대개 시스템의 볼륨을 많이 차지한다.따라서, 현대적인 통신의 빠른 발전과 더불어, Balun의 크기를 줄이는 것은 RF시스템을 만드는 데 있어서 주요한 도전이다.이 논문에서는 open-stub을 사용한 결합 라인을 사용한 벌룬 필터의 새로운 크기 축소 방법이 제시되어 있다.이 논문는 0.88 GHz(기가 바이트)를 중심으로 시뮬레이션을 했고,이를 바탕으로 모의PCB기판을 장착해 모의 실험을 했다. 새로운 디자인의 특징은 FR4폭시 글라스 구리 커버(CCL)PCB기판기질에 중앙 주파수(0.88 GHz)을 가공하기전에 ADS및 HFSS를 시뮬레이션을 한 것이다.이 논문에서는 이론과 방법이 충분히 설명되어 있다.극도로 소형화 전송 선로 필터는 18.7도의 결합선과 PCB기판에서 조립된 중앙 주파수 0.88GHz로 작동되는것으로 구성되어 비스듬하게 짧은 결합선의 집중 콘덴서에 근거한다.Balun filter의 삽입 손실은 -3dB이고 전체 회로의 크기는 30mm×16mm이다.실험 결과는 모의 실험 결과와 거의 일치한다.이론적이고, 시뮬레이션된 그리고 측정된 결과들은 모두 논문에서 증명되었다.최종 실험적 검증은 제안된 트랜스미션 라인 필터 등의 실용성과 이점을 확인한다.Contents I Abstract 1 CHAPTER 1 Introduction 3 1.1 RF filter introduction and basic parameters 3 1.2 Background and Introduction of Balun 5 1.3 Organization of the Thesis 9 CHAPTER 2 Balun Filter Design Theory 11 2.1 Size Reduction Method 11 2.1.1 Diagonally Shorted Coupled Lines with Lumped Capacitors 12 2.1.2 Parallel End Shorted Coupled Lines with Lumped Capacitors 16 2.2 The Open-stub Equivalent Circuit 19 2.3 Ordinary Balun Design 21 2.4 New Structure for Miniaturized Balun Filter 24 CHAPTER 3 Simulation, Fabrication and Measurement 30 3.1 Circuit Simulating by ADS and Analysis 30 3.1.1 Circuit Simulating of original coupled line circuit 32 3.1.2 The equivalent Circuit Simulating by adding a open-stub to act in capacitive 34 3.2 Simulation by HFSS and Optimization 38 3.3 Fabrication and Measurement 42 Chapter 4 Conclusion 46 References 47 Acknowledgement 50Maste

Multi-Layer Ultra-Wideband Wilkinson Combiner for Arrays

This work investigates an ultra-wideband (UWB), compact, and multilayer Wilkinson power combiners for tightly coupled array (TCA) designs. The Wilkinson topology designs encompass UHF, L-, and S-bands. These combiners integrate into an experimental UWB TCA. The experimental UWB TCA divides into twenty-four columns, with each column containing eight unit cells, and each cell one-inch square. The Wilkinson power combiner contains eight input ports and one output port. Twenty-four combiners mount to the TCA’s back. The combiner condenses the two-dimensional array (8x24) to a one-dimensional or linear array (1x24). The proposed Wilkinson power combiner possesses a multilayer design reducing common mode current problems caused by vias. The Wilkinson combiner covers 500 MHz to 3.28 GHz and provides a 6.56:1 bandwidth. It achieves tight impedance matching through stripline coupling. The proposed design provides minimal phase error, equal power reception, and low power handling. The power combiner interfaces with an experimental UWB TCA antenna through SMP snap connectors. This paper examines signal combining efficiency to provide minimum path loss. This paper also examines interconnecting transmission lines traversing multiple laminate layers. This necessitates proper current handling because interconnects influence impedance, transmission, and isolation. Integrating a via picket fence improves port isolation and reduces propagating parallel plate modes. The proposed combiner design achieved the following important attributes at or better than the minimum required specifications. The measured combiner design successfully demonstrated -7.8dB minimum return loss for input and -18.1dB return loss for the outputs; 10.92dB ± 1.28dB insertion loss; -12.2db minimum isolation; ± 1.38° minimal phase error; ± 0.57dB power reception imbalance. The proposed UWB combiner design condensed the four-stage Wilkinson footprint to consume no more than 0.4in² (258mm²) surface area, weighed only 1.5oz (42.5g), and less than a half-inch thick

Advanced design of microwave power divider with enhanced harmonic suppression.

Ip, Wei Chi.Thesis (M.Phil.)--Chinese University of Hong Kong, 2011.Includes bibliographical references (leaves 92-94).Abstracts in English and Chinese.Abstract --- p.i摘要 --- p.iiAcknowledgement --- p.iiiTable of Content --- p.ivLists of Figures --- p.viiLists of Tables --- p.xiiChapter Chapter 1: --- Introduction --- p.1Chapter 1.1 --- Research Motivation and Obj ective --- p.1Chapter 1.2 --- Original Contribution --- p.2Chapter 1.3 --- Overview of the Thesis Organization --- p.3Chapter 1.4 --- "Research Approach, Assumptions and Limitations" --- p.4Chapter Chapter 2: --- Power Divider Design Fundamentals --- p.5Chapter 2.1 --- Power Divider Basics --- p.5Chapter 2.2 --- Wilkinson Power Divider --- p.6Chapter 2.3 --- Power Divider with Unequal Power Division --- p.8Chapter 2.4 --- Multi-way Power Divider --- p.9Chapter 2.4.1 --- Wilkinson N-way Hybrid --- p.10Chapter 2.4.2 --- Radial Hybrid --- p.11Chapter 2.4.3 --- Fork Hybrid --- p.12Chapter 2.4.4 --- Multi-layer Approach --- p.ISChapter 2.4.5 --- Power Recombination Concept --- p.15Chapter 2.4.6 --- Multi-coupled-line Approach --- p.18Chapter Chapter 3: --- Conventional Power Divider Designs with Harmonic Suppression --- p.20Chapter 3.1 --- Resonating-stubs Topology --- p.20Chapter 3.2 --- Asymmetric Defected Ground Structure (DGS) --- p.26Chapter 3.3 --- Anti-Coupled Line Structure --- p.30Chapter 3.4 --- Microstrip Electromagnetic Bandgap (EBG) Based Topology --- p.32Chapter 3.5 --- Embedded Resonators Topology --- p.37Chapter 3.6 --- Extended Line Approach --- p.39Chapter Chapter 4: --- New 2-way Power Divider Design with Spurious Suppression and Impedance Transformation --- p.41Chapter 4.1 --- Proposed Topology --- p.41Chapter 4.2 --- Design and Analysis --- p.42Chapter 4.3 --- Simulation Study --- p.45Chapter 4.4 --- Experimental Verification --- p.50Chapter 4.5 --- Summary --- p.57Chapter Chapter 5: --- New 2-way Power Divider Design with Extended Spurious Suppression --- p.58Chapter 5.1 --- Proposed Topology --- p.58Chapter 5.2 --- Design and Analysis --- p.59Chapter 5.3 --- Simulation Study --- p.64Chapter 5.3 --- Experimental Verification --- p.68Chapter 5.4 --- Summary --- p.71Chapter Chapter 6: --- New 2-way Unequal Power Divider Design with Dual-harmonic Rejection --- p.72Chapter 6.1 --- Proposed Topology --- p.72Chapter 6.2 --- Design and Analysis --- p.73Chapter 6.3 --- Simulation Study --- p.76Chapter 6.4 --- Experimental Verification --- p.77Chapter 6.4 --- Summary --- p.80Chapter Chapter 7: --- New 3-way Power Divider Design with Multi-harmonic Rejection..… --- p.81Chapter 7.1 --- Proposed Topology --- p.81Chapter 7.2 --- Design and Analysis --- p.82Chapter 7.3 --- Simulation Study --- p.85Chapter 7.4 --- Experimental Verification --- p.87Chapter 7.4 --- Summary --- p.90Chapter Chapter 8: --- Conclusion --- p.91References --- p.92Author's Publications and Awards --- p.95Chapter Appendix 1: --- ABCD Parameters of Some Useful Two-port Circuits --- p.96Chapter Appendix 2: --- More Designs of Proposed Configuration in Chapter 5 --- p.97Chapter A2.1 --- Miniaturized version of Example 1 --- p.97Chapter A2.2 --- Design with improved stop-band response --- p.101Chapter A2.3 --- Design of prototype with 2 GHz operating frequency --- p.104Chapter Appendix 3: --- Brief Summary of Power Dividers with Harmonic Suppression --- p.10

Nouvelles Topologies des diviseurs de puissance, balun et déphaseurs en bandes RF et millimétiques, apport des lignes à ondes lentes

L objectif de cette thèse a été premièrement de réaliser des dispositifs passifs intégrés à base de lignes à onde lentes nommées S-CPW (pour Slow-wave CoPlanar Waveguide ) aux fréquences millimétriques. Plusieurs technologies CMOS ou BiCMOS ont été utilisées: CMOS 65 nm et 28 nm ainsi que BiCMOS 55 nm. Deux baluns, le premier basé sur une topologie de rat-race et le second basé sur un diviseur de puissance de Wilkinson modifié, ainsi qu un inverseur de phase, ont été réalisés et mesurés dans la technologie CMOS 65 nm. Les résultats expérimentaux obtenus se situent à l état de l art en termes de performances électriques. Un coupler hybride et un diviseur de puissance avec des sorties en phase sans isolation ont été conçus en technologie CMOS 28 nm. Les simulations montrent de très bonnes performances pour des dispositifs compacts. Les circuits sont en cours de fabrication et pourront très bientôt être caractérisés. Ensuite, une nouvelle topologie de diviseurs de puissance, avec sorties en phase et isolé a été développée, offrant une grande flexibilité et compacité en comparaison des diviseurs de puissance traditionnels. Cette topologie est parfaitement adaptée pour les technologies silicium. Comme preuve de concept, deux diviseurs de puissance avec des caractéristiques différentes ont été réalisés en technologie PCB microruban à la fréquence de 2.45 GHz. Un composent a été conçu à 60 GHz en technologie BiCMOS 55 nm utilisant des lignes S CPW. Les simulations prouvent que le dispositif est faibles pertes, adapté et isolé. Les circuits sont également en cours de fabrication. Enfin, deux topologies de reflection type phase shifter ont été développées, la première dans la bande RF et la seconde aux fréquences millimétrique. Pour la bande RF, le déphasage atteint plus de 360 avec une figure de mérite très élevée en comparaison avec l état de l art. En ce qui concerne le déphaseur dans la bande millimétrique, la simulation montre un déphasage de 341 avec également une figure de mérite élevée.The first purpose of this work was the use of slow-wave coplanar waveguides (S CPW) to achieve various passive components with the aim to show their great potential and interest at millimetre-waves. Several CMOS or BiCMOS technologies were used: CMOS 65 nm and 28 nm, and BiCMOS 55 nm. Two baluns, one based on a rat-race topology and the other based on a modified Wilkinson power divider, and a phase inverter, were achieved and measured in a 65 nm CMOS technology. State-of-the-art results were achieved. A branch-line coupler and an in phase power divider without isolation were designed in a 28 nm CMOS technology. Really good performances are expected for these compact devices being yet under fabrication. Then, a new topology of in phase and isolated power divider was developed, leading to more flexibility and compactness, well suited to millimetre-wave frequencies. Two power dividers with different characteristics were realized in a PCB technology at 2.45 GHz by using microstrip lines, as a proof-of-concept. After that, a power divider was designed at the working frequency of 60 GHz in the 55 nm BiCMOS technology with S CPWs. The simulation results showed a low loss, full-matched and isolated component, which is also under fabrication and will be characterized as soon as possible. Finally, two new topologies of reflection type phase shifters were presented, one for the RF band and one for the millimetre-wave one. For the one in RF band, the phase shift can reach more than 360 with a great figure-of-merit as compared to the state-of-the-art. Concerning the phase shifter in the millimetre-wave band, the simulation results show a phase shift of 341 with also a high figure-of-merit.SAVOIE-SCD - Bib.électronique (730659901) / SudocGRENOBLE1/INP-Bib.électronique (384210012) / SudocGRENOBLE2/3-Bib.électronique (384219901) / SudocSudocFranceF

Basics of RF electronics

RF electronics deals with the generation, acquisition and manipulation of high-frequency signals. In particle accelerators signals of this kind are abundant, especially in the RF and beam diagnostics systems. In modern machines the complexity of the electronics assemblies dedicated to RF manipulation, beam diagnostics, and feedbacks is continuously increasing, following the demands for improvement of accelerator performance. However, these systems, and in particular their front-ends and back-ends, still rely on well-established basic hardware components and techniques, while down-converted and acquired signals are digitally processed exploiting the rapidly growing computational capability offered by the available technology. This lecture reviews the operational principles of the basic building blocks used for the treatment of high-frequency signals. Devices such as mixers, phase and amplitude detectors, modulators, filters, switches, directional couplers, oscillators, amplifiers, attenuators, and others are described in terms of equivalent circuits, scattering matrices, transfer functions; typical performance of commercially available models is presented. Owing to the breadth of the subject, this review is necessarily synthetic and non-exhaustive. Readers interested in the architecture of complete systems making use of the described components and devoted to generation and manipulation of the signals driving RF power plants and cavities may refer to the CAS lectures on Low-Level RF.Comment: 36 pages, contribution to the CAS - CERN Accelerator School: Specialised Course on RF for Accelerators; 8 - 17 Jun 2010, Ebeltoft, Denmar

On the design of high-efficiency RF Doherty power amplifiers

Power amplifiers (PAs) are one of the most crucial elements in wireless standards becasue they are the most power hungry subsystems. These elements have to face an important issue, which is the power efficiency, a fact related with the output back-off (OBO). But the OBO depends on the kind of modulated signal, in proportion to the modulated signal peak-to-average power ratio (PAPR). The higuer is the data rate, the higer is the OBO, and consequently the lower is the efficiency. A low efficiency of PAs causes the waste of energy as heat. Furthermore, the trade-off between linearity and efficiency in PAs is another major issue. To cope with the undesired circumstances producing efficiency degradation, the Doherty power amplifier (DPA) is one of the useful techniques which provide high efficiency for high PAPR of modern communication signals. Nevertheless, the limited bandwidth (BW) of this kind of PAs (about 10% of fractional bandwidth) and its importance (in modern wireless systems such as LTE, WiMAX, Wi-Fi and satellite systems) have encouraged the researchers to improve this drawback in recent years. Some typical BW limiting factors effect on the performance of DPAs: i) quarter-wave length transformers, ii) phase compensation networks in/output matching circuits, iii) offset lines and device non-idealities; The quarter-wave length transformers performs as an inverter impedance in the load modulation technique of DPAs. The future objective in designing DPAs is to decrease the impact of these issues. In this context, this PhD-thesis is focused on improving fractional bandwidth of DPAs using the new methods that are related to impedance transformers instead of impedance inverters in the load modulation technique. This study is twofold. First, it is presented a novel DPA where a wideband GaN DPA in the 2.5 GHz band with an asymmetrical Wilkinson splitter. The impedance transformer of the proposed architecture is based on a matching network including a tapered line with multi-section transformer in the main stage. The BW of this DPA has ranged from 1.8 to 2.7 GHz. Plus, the obtained power efficiency (drain) is higher than 33% in the whole BW at both maximum and OBO power levels. Second, based on the benefits of the Klopfenstein taper, a promising DPA design is proposed where a Klopfenstein taper replaces the tapered line. In fact, this substitution results on reducing the reflection coefficient of the transformer. From a practical prototype realization of this novel Doherty-like PA in the 2.25 GHz band, this modification has demonstrated that the resulting DPA BW is increased in comparison to the conventional topology while keeping the efficiency figures. Moreover, this study also shows that the Klopfenstein taper based design allows an easy tuning of the group delay through the output reactance of the taper, resulting in a more straightforward adjustments than other recently published designs where the quarter-wave transformer is replaced by multi-section transmission lines (hybrid or similar). Experimental results have shown 43-54% of drain efficiency at 42 dBm output power, in the range of 1.7 to 2.75 GHz. Concretely, the results presented in this novel Doherty-like PA implies an specific load modulation technique that uses the mixed Klopfenstein tapered line together with a multi-section transformer in order to obtain high bandwidth with the usual efficiency in DPAs.Los amplificadores de potencia (PAs) son uno de los elementos más importantes para los transmisores inalámbricos desde el punto de vista del consumo energético. Un aspecto muy importante es su eficiencia energética, un concepto relacionado con el back-off de salida (OBO), que a su vez viene condicionadpo por el PAPR de la señal modulada a amplificar. Una baja eficiencia de los PA hace que la pérdida de energía se manifieste en forma de calor. De hecho, esta cuestión conduce al incremento de los costes y tamaño, esto último por los radiadores. Además, el compromiso entre la linealidad y la eficiencia en los PA es otro problema importante. Para hacer frente a las circunstancias que producen la degradación de la eficiencia, el amplificador de potencia tipo Doherty (DPA) es una de las técnicas más útiles que proporcionan una buena eficiencia incluso para los altos PAPR comunes en señales de comunicación modernos. Sin embargo, el limitado ancho de banda (BW) de este tipo de PA (alrededor del 10% del ancho de banda fraccional) y su importancia (en los sistemas inalámbricos modernos, tales como LTE, WiMAX, Wi-Fi y sistemas de satélites) han animado a los investigadores para mejorar este inconveniente en los últimos años. Algunos aspectos típicos que limitan el BW en los DPA son: i) transformadores de longitud de cuarto de onda, ii) redes de compensación de fase y circuitos de adaptación de salida, iii) compensación de las líneas y los dispositivos no ideales. Los transformadores de cuarto de onda actuan como un inversor de impedancia en la técnica de modulación de carga de la DPA "("load modulation"). Concretamente, el objetivo futuro de diseño de DPA es disminuir el impacto de estos problemas. En este contexto, esta tesis doctoral se centra en mejorar el ancho de banda fraccional de DPA utilizando los nuevos métodos que están relacionados con el uso de transformadores de impedancias en vez de inversores en el subcircuito de modulación de carga. Este estudio tiene dos niveles. En primer lugar, se presenta una novedosa estructura del DPA de banda ancha usándose dispositivos de GaN en la banda de 2,5 GHz con un divisor Wilkinson asimétrico. El transformador de impedancias de la arquitectura propuesta se basa en una red de adaptación, incluyendo una línea cónica con múltiples secciones del transformador en la etapa principal. El BW de este DPA ha sido de 1,8 a 2,7 GHz. Además, se obtiene una eficiencia de drenador de más del 33% en todo el BW, tanto a nivel de potencia máxima como a nivel del OBO. En segundo lugar, aprovechando los beneficios de un adaptador de Klopfenstein, se propone un nuevo diseño del DPA. Con la sustitución de la lina conica por el Klopfenstein se reduce el coeficiente de reflexión de transformador de impedancias. Sobre un prototipo práctico de esta nueva estructura del Doherty, en la banda de 2,25 GHz, se ha demostrado que el BW resultante se incrementa en comparación con la topología convencional mientras se mantienen las cifras de eficiencia. Por otra parte, en este estudio se demuestra que el diseño basado en el Klopfenstein permite una afinación fácil del retardo de grupo a través de la reactancia de salida del taper, lo que resulta en un ajuste más sencillo que otros diseños publicados recientemente en el que el transformador de cuarto de onda se sustituye por multi-líneas de transmisión de la sección (híbridos o similar). Los resultados experimentales han mostrado un 43-54% de eficiencia de drenador sobre 42 dBm de potencia de salida, en el intervalo de 1,7 a 2,75 GHz. Concretamente, los resultados presentados en esta nueva estructura tipo-Doherty implican una técnica de modulación de carga que utiliza una combinación de un Klopfenstein junto con un transformador de múltiples secciones con el fin de obtener un alto ancho de banda con la eficiencia habitual en DPAs.Els amplificadors de potència (PA) són un dels elements més importants per els sistemes ràdio ja que sone ls principals consumidors d'energía. Un aspecte molt important és l'eficiència de l'amplificador, aspecte relacionat amb el back-off de sortida (OBO) que a la seva vegada ve condicionat pel PAPR del senyal modulat. Una baixa eficiència dels PA fa que la pèrdua d'energia en manifesti en forma de calor. De fet, aquesta qüestió porta a l'increment dels costos i grandària, degut als dissipadors de calor. A més, el compromís entre la linealitat i l'eficiència en els PA es un altre problema important. Per fer front a les circumstàncies que porten a la degradació de l'eficiència, l'amplificador de potència Doherty (DPA) és una de les tècniques més útils i que proporcionen una bona eficiència per als alts PAPR comuns en senyals de comunicació moderns. No obstant això, l'ample de banda limitat (BW) d'aquest tipus de PA (al voltant del 10% de l'ample de banda fraccional) i la seva importància (en els sistemes moderns, com ara LTE, WiMAX, Wi-Fi i sistemes de satèl·lits) han animat els investigadors per millorar aquest inconvenient en els últims anys. Alguns aspectes tipicament limitadors del BW en els DPA son: i) transformadors de longitud d'quart d'ona, ii) xarxes de compensació de fase en circuits / adaptacions de sortida, iii) compensació de les línies i els dispositius no ideals. Els transformadors de quart d'ona s'utilitzen com a inversors d'impedàncies en la tècnica de modulació de càrrega del DPA ("load modulation"). Concretament, l'objectiu futur de disseny d'DPA és disminuir l'impacte d'aquests problemes. En aquest context, aquesta tesi doctoral es centra en millorar l'ample de banda fraccional dels DPA utilitzant nous mètodes que estan relacionats amb l'ús de transformadors d'impedàncies, en comptes d'inversors, en el subcircuit de modulació de càrrega. Aquest treball té dos nivells. En primer lloc, es presenta un DPA novedós que fa servir dispositus GaN DPA a la banda de 2,5 GHz amb un divisor Wilkinson asimètric. El transformador d'impedàncies de l'arquitectura proposada es basa en una xarxa d'adaptació, incloent una línia cònica amb múltiples seccions del transformador en l'etapa principal. El BW d'aquest DPA ha mostrat ser d'1,8 a a 2,7 GHz. A més, s'obté una eficiència de drenador de més del 33% en tot el BW, tant a nivell de potència màxima com de OBO. En segon lloc, sobre la base dels beneficis del adaptador de Klopfenstein, un proposa un nou disseny on un Klopfenstein substitueix la anterior línia cònica. Aquesta substitució repercuteix en la reducció del coeficient de reflexió de transformador d'impedàncies.Des d'una realització pràctica (prototipus) d'aquest nou amplificador tipus Doherty a la banda de 2,25 GHz, s'ha demostrat que el BW resultant s'incrementa en comparació amb la topologia convencional mentre es mantenen les xifres d'eficiència. D'altra banda, en aquest estudi es demostra que el disseny basat en el Klopfenstein permet una afinació fàcil del retard de grup a través de la reactància de sortida de la forma cònica, el que resulta en un ajust més senzill que altres dissenys publicats recentment en què el transformador de quart d'ona es substitueix per multi-línies de transmissió de la secció (híbrids o similar). Els resultats experimentals han mostrat un 43-54% d'eficiència de drenador en 42 dBm de potència de sortida, en l'interval de 1,7-2,75 GHz. Concretament, els resultats presentats en aquest nou amplificador tipus Doherty impliquen una tècnica de modulació de càrrega específic que utilitza una combinació del Klopfenstein juntament amb un transformador de múltiples seccions per tal d'obtenir un alt ample de banda amb la usual eficiència en DPAs.Postprint (published version

An Extremely Miniaturized Microstrip Balun Filter

The field of RF (radio frequency) and microwave is rapidly growing because of its use in wireless communication systems. In wireless applications, baluns which frequently connect a bandpass filter with a balanced component are significant system factors but usually occupy much of the volume of the systems.Thus, with the speedy development of modern communication, reducing the size of balun is the main challenge in making RF systems compact. In addition, the poor balanced port matching and isolation performance of many conventional baluns limits their application. In this thesis, a novel enhanced balun bandpass filter for extremely miniaturization is demonstrated utilizing the combination of diagonally shorted coupled lines and parallel end shorted coupled lines both with shunt lumped capacitors. This method can largely reduce the required electrical length of transmission line, not only approximately maintaining the same characteristic around the center frequency but also effectively suppressing the spurious passband.Meanwhile, a resistive network between the outputs is presented to realize the balanced matching and isolation. Comparing with the typical Marchand Balun, it takes better performance as well as shows a wider upper stopband. Design equations and method is fully explained in this thesis. An extremely miniaturized balun filter operating at 1GHz of microstrip line form is fabricated on PCB substrate with 15 degree electrical length of the coupled lines. Both theoretical and measured performances are displayed. The experimental verification proves the usefulness of the proposed balun filter and its advantages of the application for mobile communications, etc.Contents ..................................................................................................................... I Nomenclature ............................................................................................................ II List of Tables ........................................................................................................... III List of Figures ......................................................................................................... III Abstract ..................................................................................................................... V CHAPTER 1 Introduction ......................................................................................... 1 1.1 Background and Introduction of Balun ........................................................ 1 1.2 Organization of the Thesis ........................................................................... 6 CHAPTER 2 Balun Filter Design Theory ................................................................ 7 2.1 Size Reduction Method ................................................................................ 7 2.1.1 Diagonally Shorted Coupled Lines with Lumped Capacitors ........... 8 2.1.2 Parallel End Shorted Coupled Lines with Lumped Capacitors......... 11 2.2 Ordinary Balun Design .............................................................................. 14 2.3 New Structure for Miniaturized Balun Filter ............................................. 16 2.4 Isolation and Matching Network of Balanced Outputs .............................. 19 CHAPTER 3 Simulation, Fabrication and Measurement ....................................... 23 3.1 Circuit Simulating by ADS and Analysis ................................................... 23 3.2 Full-Wave EM Simulation by HFSS and Optimization ............................. 28 3.3 Fabrication and Measurement .................................................................... 32 Chapter 4 Conclusion .............................................................................................. 39 References ............................................................................................................... 40 Acknowledgement .................................................................................................. 4

Microwave and Millimeter-Wave Multi-Band Power Amplifiers, Power Combining Networks, and Transmitter Front-End in Silicon Germanium BiCMOS Technology

This dissertation presents new circuit architectures and techniques for designing high performance microwave and millimeter-wave circuits using 0.18-µm SiGe BiCMOS process for advanced wireless communication and sensing systems. The high performance single- and multi-band power amplifiers working in microwave and millimeter-wave frequency ranges are proposed. A 10-19, 23-39, and 33-40 GHz concurrent tri-band power amplifier in the respective Ku-, K-, and Ka-band using the distributed amplifier structure is presented first. Instead of utilizing multi-band matching networks, this amplifier is realized based on distributed amplifier structure and two active notch filters employed at each gain cell to form tri-band response. In addition, a power amplifier operating across the entire K-band is proposed. By employing lumped-element Wilkinson power divider and combiner, it produces high output power, high gain, and power added efficiency characteristics over broadband due to its inherent low-pass filtering response. Moreover, a highly integrated V-band power amplifier is presented. This power amplifier consists of four medium unit power cells combined with a four-way parallel power combining network. Secondly, microwave and millimeter-wave power combining and dividing networks are proposed. A wideband power divider and combiner operating up to 67 GHz is developed by adopting capacitive loading slow-wave transmission line to reduce size as well as insertion loss. Also, two-way and 16-way 24/60 GHz dual-band power divider networks in the K/V-band are proposed. The two-way dual-band power divider is realized with a slow-wave transmission line and two shunt connected LC resonators in order to minimize the chip size as well as insertion loss. Furthermore, a 16-way dual-band power dividing and combining network is developed for a dual-band 24/60 GHz 4×4 array system. This network incorporates a two-way dual-band power divider, lumped-element based Wilkinson power dividers, and multi-section transmission line based Wilkinson structures. Finally, a K-/V-band dual-band transmitter front-end is proposed. To realize the transmitter, a diplexer with good diplexing performance and K- and V-band variable gain amplifiers having low phase variation with gain tuning are designed. The transmitter is integrated with two diplexers, K- and V-band variable gain amplifiers, and two power amplifiers resulting in high gain, high output power, and low-phase variation with all gain control stages