156 research outputs found

    A 0.18”m CMOS UWB wireless transceiver for medical sensing applications

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    Recently, there is a new trend of demand of a biomedical device that can continuously monitor patient’s vital life index such as heart rate variability (HRV) and respiration rate. This desired device would be compact, wearable, wireless, networkable and low-power to enable proactive home monitoring of vital signs. This device should have a radar sensor portion and a wireless communication link all integrated in one small set. The promising technology that can satisfy these requirements is the impulse radio based Ultra-wideband (IR-UWB) technology. Since Federal Communications Commission (FCC) released the 3.1GHz-10.6GHz frequency band for UWB applications in 2002 [1], IR-UWB has received significant attention for applications in target positioning and wireless communications. IR-UWB employs extremely narrow Gaussian monocycle pulses or any other forms of short RF pulses to represent information. In this project, an integrated wireless UWB transceiver for the 3.1GHz-10.6GHz IR-UWB medical sensor was developed in the 0.18”m CMOS technology. This UWB transceiver can be employed for both radar sensing and communication purposes. The transceiver applies the On-Off Keying (OOK) modulation scheme to transmit short Gaussian pulse signals. The transmitter output power level is adjustable. The fully integrated UWB transceiver occupies a core area of 0.752mm^2 and the total die area of 1.274mm^2 with the pad ring inserted. The transceiver was simulated with overall power consumption of 40mW for radar sensing. The receiver is very sensitive to weak signals with a sensitivity of -73.01dBm. The average power of a single pulse is 9.8”W. The pulses are not posing any harm to human tissues. The sensing resolution and the target positioning precision are presumably sufficient for heart movement detection purpose in medical applications. This transceiver can also be used for high speed wireless data communications. The data transmission rate of 200 Mbps was achieved with an overall power consumption of 57mW. A combination of sensing and communications can be used to build a low power sensor

    Ultra Wideband

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    Ultra wideband (UWB) has advanced and merged as a technology, and many more people are aware of the potential for this exciting technology. The current UWB field is changing rapidly with new techniques and ideas where several issues are involved in developing the systems. Among UWB system design, the UWB RF transceiver and UWB antenna are the key components. Recently, a considerable amount of researches has been devoted to the development of the UWB RF transceiver and antenna for its enabling high data transmission rates and low power consumption. Our book attempts to present current and emerging trends in-research and development of UWB systems as well as future expectations

    Ultra Wideband Communications: from Analog to Digital

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    ï»żUltrabreitband-Signale (Ultra Wideband [UWB]) können einen signifikanten Nutzen im Bereich drahtloser Kommunikationssysteme haben. Es sind jedoch noch einige Probleme offen, die durch Systemdesigner und Wissenschaftler gelöst werden mĂŒssen. Ein Funknetzsystem mit einer derart großen Bandbreite ist normalerweise auch durch eine große Anzahl an Mehrwegekomponenten mit jeweils verschiedenen Pfadamplituden gekennzeichnet. Daher ist es schwierig, die zeitlich verteilte Energie effektiv zu erfassen. Außerdem ist in vielen FĂ€llen der naheliegende Ansatz, ein kohĂ€renter EmpfĂ€nger im Sinne eines signalangepassten Filters oder eines Korrelators, nicht unbedingt die beste Wahl. In der vorliegenden Arbeit wird dabei auf die bestehende Problematik und weitere Lösungsmöglichkeiten eingegangen. Im ersten Abschnitt geht es um „Impulse Radio UWB”-Systeme mit niedriger Datenrate. Bei diesen Systemen kommt ein inkohĂ€renter EmpfĂ€nger zum Einsatz. InkohĂ€rente Signaldetektion stellt insofern einen vielversprechenden Ansatz dar, als das damit aufwandsgĂŒnstige und robuste Implementierungen möglich sind. Dies trifft vor allem in AnwendungsfĂ€llen wie den von drahtlosen Sensornetzen zu, wo preiswerte GerĂ€te mit langer Batterielaufzeit nötigsind. Dies verringert den fĂŒr die KanalschĂ€tzung und die Synchronisation nötigen Aufwand, was jedoch auf Kosten der Leistungseffizienz geht und eine erhöhte Störempfindlichkeit gegenĂŒber Interferenz (z.B. Interferenz durch mehrere Nutzer oder schmalbandige Interferenz) zur Folge hat. Um die Bitfehlerrate der oben genannten Verfahren zu bestimmen, wurde zunĂ€chst ein inkohĂ€renter Combining-Verlust spezifiziert, welcher auftritt im Gegensatz zu kohĂ€renter Detektion mit Maximum Ratio Multipath Combining. Dieser Verlust hĂ€ngt von dem Produkt aus der LĂ€nge des Integrationsfensters und der Signalbandbreite ab. Um den Verlust durch inkohĂ€rentes Combining zu reduzieren und somit die Leistungseffizienz des EmpfĂ€ngers zu steigern, werden verbesserte Combining-Methoden fĂŒr Mehrwegeempfang vorgeschlagen. Ein analoger EmpfĂ€nger, bei dem der Hauptteil des Mehrwege-Combinings durch einen „Integrate and Dump”-Filter implementiert ist, wird fĂŒr UWB-Systeme mit Zeit-Hopping gezeigt. Dabei wurde die Einsatzmöglichkeit von dĂŒnn besetzten Codes in solchen System diskutiert und bewertet. Des Weiteren wird eine Regel fĂŒr die Code-Auswahl vorgestellt, welche die StabilitĂ€t des Systems gegen Mehrnutzer-Störungen sicherstellt und gleichzeitig den Verlust durch inkohĂ€rentes Combining verringert. Danach liegt der Fokus auf digitalen Lösungen bei inkohĂ€renter Demodulation. Im Vergleich zum AnalogempfĂ€nger besitzt ein DigitalempfĂ€nger einen Analog-Digital-Wandler im Zeitbereich gefolgt von einem digitalen Optimalfilter. Der digitale Optimalfilter dekodiert den Mehrfachzugriffscode kohĂ€rent und beschrĂ€nkt das inkohĂ€rente Combining auf die empfangenen Mehrwegekomponenten im Digitalbereich. Es kommt ein schneller Analog-Digital-Wandler mit geringer Auflösung zum Einsatz, um einen vertretbaren Energieverbrauch zu gewĂ€hrleisten. Diese Digitaltechnik macht den Einsatz langer Analogverzögerungen bei differentieller Demodulation unnötig und ermöglicht viele Arten der digitalen Signalverarbeitung. Im Vergleich zur Analogtechnik reduziert sie nicht nur den inkohĂ€renten Combining-Verlust, sonder zeigt auch eine stĂ€rkere Resistenz gegenĂŒber Störungen. Dabei werden die Auswirkungen der Auflösung und der Abtastrate der Analog-Digital-Umsetzung analysiert. Die Resultate zeigen, dass die verminderte Effizienz solcher Analog-Digital-Wandler gering ausfĂ€llt. Weiterhin zeigt sich, dass im Falle starker Mehrnutzerinterferenz sogar eine Verbesserung der Ergebnisse zu beobachten ist. Die vorgeschlagenen Design-Regeln spezifizieren die Anwendung der Analog-Digital-Wandler und die Auswahl der Systemparameter in AbhĂ€ngigkeit der verwendeten Mehrfachzugriffscodes und der Modulationsart. Wir zeigen, wie unter Anwendung erweiterter Modulationsverfahren die Leistungseffizienz verbessert werden kann und schlagen ein Verfahren zur UnterdrĂŒckung schmalbandiger Störer vor, welches auf Soft Limiting aufbaut. Durch die Untersuchungen und Ergebnissen zeigt sich, dass inkohĂ€rente EmpfĂ€nger in UWB-Kommunikationssystemen mit niedriger Datenrate ein großes Potential aufweisen. Außerdem wird die Auswahl der benutzbaren Bandbreite untersucht, um einen Kompromiss zwischen inkohĂ€rentem Combining-Verlust und StabilitĂ€t gegenĂŒber langsamen Schwund zu erreichen. Dadurch wurde ein neues Konzept fĂŒr UWB-Systeme erarbeitet: wahlweise kohĂ€rente oder inkohĂ€rente EmpfĂ€nger, welche als UWB-Systeme Frequenz-Hopping nutzen. Der wesentliche Vorteil hiervon liegt darin, dass die Bandbreite im Basisband sich deutlich verringert. Mithin ermöglicht dies einfach zu realisierende digitale Signalverarbeitungstechnik mit kostengĂŒnstigen Analog-Digital-Wandlern. Dies stellt eine neue Epoche in der Forschung im Bereich drahtloser Sensorfunknetze dar. Der Schwerpunkt des zweiten Abschnitts stellt adaptiven Signalverarbeitung fĂŒr hohe Datenraten mit „Direct Sequence”-UWB-Systemen in den Vordergrund. In solchen Systemen entstehen, wegen der großen Anzahl der empfangenen Mehrwegekomponenten, starke Inter- bzw. Intrasymbolinterferenzen. Außerdem kann die FunktionalitĂ€t des Systems durch Mehrnutzerinterferenz und Schmalbandstörungen deutlich beeinflusst werden. Um sie zu eliminieren, wird die „Widely Linear”-Rangreduzierung benutzt. Dabei verbessert die Rangreduzierungsmethode das Konvergenzverhalten, besonders wenn der gegebene Vektor eine sehr große Anzahl an Abtastwerten beinhaltet (in Folge hoher einer Abtastrate). ZusĂ€tzlich kann das System durch die Anwendung der R-linearen Verarbeitung die Statistik zweiter Ordnung des nicht-zirkularen Signals vollstĂ€ndig ausnutzen, was sich in verbesserten SchĂ€tzergebnissen widerspiegelt. Allgemeine kann die Methode der „Widely Linear”-Rangreduzierung auch in andern Bereichen angewendet werden, z.B. in „Direct Sequence”-Codemultiplexverfahren (DS-CDMA), im MIMO-Bereich, im Global System for Mobile Communications (GSM) und beim Beamforming.The aim of this thesis is to investigate key issues encountered in the design of transmission schemes and receiving techniques for Ultra Wideband (UWB) communication systems. Based on different data rate applications, this work is divided into two parts, where energy efficient and robust physical layer solutions are proposed, respectively. Due to a huge bandwidth of UWB signals, a considerable amount of multipath arrivals with various path gains is resolvable at the receiver. For low data rate impulse radio UWB systems, suboptimal non-coherent detection is a simple way to effectively capture the multipath energy. Feasible techniques that increase the power efficiency and the interference robustness of non-coherent detection need to be investigated. For high data rate direct sequence UWB systems, a large number of multipath arrivals results in severe inter-/intra-symbol interference. Additionally, the system performance may also be deteriorated by multi-user interference and narrowband interference. It is necessary to develop advanced signal processing techniques at the receiver to suppress these interferences. Part I of this thesis deals with the co-design of signaling schemes and receiver architectures in low data rate impulse radio UWB systems based on non-coherent detection.● We analyze the bit error rate performance of non-coherent detection and characterize a non-coherent combining loss, i.e., a performance penalty with respect to coherent detection with maximum ratio multipath combining. The thorough analysis of this loss is very helpful for the design of transmission schemes and receive techniques innon-coherent UWB communication systems.● We propose to use optical orthogonal codes in a time hopping impulse radio UWB system based on an analog non-coherent receiver. The “analog” means that the major part of the multipath combining is implemented by an integrate and dump filter. The introduced semi-analytical method can help us to easily select the time hopping codes to ensure the robustness against the multi-user interference and meanwhile to alleviate the non-coherent combining loss.● The main contribution of Part I is the proposal of applying fully digital solutions in non-coherent detection. The proposed digital non-coherent receiver is based on a time domain analog-to-digital converter, which has a high speed but a very low resolution to maintain a reasonable power consumption. Compared to its analog counterpart, itnot only significantly reduces the non-coherent combining loss but also offers a higher interference robustness. In particular, the one-bit receiver can effectively suppress strong multi-user interference and is thus advantageous in separating simultaneously operating piconets.The fully digital solutions overcome the difficulty of implementing long analog delay lines and make differential UWB detection possible. They also facilitate the development of various digital signal processing techniques such as multi-user detection and non-coherent multipath combining methods as well as the use of advanced modulationschemes (e.g., M-ary Walsh modulation).● Furthermore, we present a novel impulse radio UWB system based on frequency hopping, where both coherent and non-coherent receivers can be adopted. The key advantage is that the baseband bandwidth can be considerably reduced (e.g., lower than 500 MHz), which enables low-complexity implementation of the fully digital solutions. It opens up various research activities in the application field of wireless sensor networks. Part II of this thesis proposes adaptive widely linear reduced-rank techniques to suppress interferences for high data rate direct sequence UWB systems, where second-order non-circular signals are used. The reduced-rank techniques are designed to improve the convergence performance and the interference robustness especially when the received vector contains a large number of samples (due to a high sampling rate in UWB systems). The widely linear processing takes full advantage of the second-order statistics of the non-circular signals and enhances the estimation performance. The generic widely linear reduced-rank concept also has a great potential in the applications of other systems such as Direct Sequence Code Division Multiple Access (DS-CDMA), Multiple Input Multiple Output (MIMO) system, and Global System for Mobile Communications (GSM), or in other areas such as beamforming

    Analog radio over fiber solutions for multi-band 5g systems

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    This study presents radio over fiber (RoF) solutions for the fifth-generation (5G) of wireless networks. After the state of the art and a technical background review, four main contributions are reported. The first one is proposing and investigating a RoF technique based on a dual-drive Mach-Zehnder modulator (DD-MZM) for multi-band mobile fronthauls, in which two radiofrequency (RF) signals in the predicted 5G bands individually feed an arm of the optical modulator. Experimental results demonstrate the approach enhances the RF interference mitigation and can prevail over traditional methods. The second contribution comprises the integration of a 5G transceiver, previously developed by our group, in a passive optical network (PON) using RoF technology and wavelength division multiplexing (WDM) overlay. The proposed architecture innovates by employing DD-MZM and enables to simultaneously transport baseband and 5G candidate RF signals in the same PON infrastructure. The proof-of-concept includes the transmission of a generalized frequency division multiplexing (GFDM) signal generated by the 5G transceiver in the 700 MHz band, a 26 GHz digitally modulated signal as a millimeter-waves 5G band, and a baseband signal from an gigabit PON (GPON). Experimental results demonstrate the 5G transceiver digital performance when using RoF technology for distributing the GFDM signal, as well as Gbit/s throughput at 26 GHz. The third contribution is the implementation of a flexible-waveform and multi-application fiber-wireless (FiWi) system toward 5G. Such system includes the FiWi transmission of the GFDM and filtered orthogonal frequency division multiplexing (F-OFDM) signals at 788 MHz, toward long-range cells for remote or rural mobile access, as well as the recently launched 5G NR standard in microwave and mm-waves, aiming enhanced mobile broadband indoor and outdoor applications. Digital signal processing (DSP) is used for selecting the waveform and linearizing the RoF link. Experimental results demonstrate the suitability of the proposed solution to address 5G scenarios and requirements, besides the applicability of using existent fiber-to-the-home (FTTH) networks from Internet service providers for implementing 5G systems. Finally, the fourth contribution is the implementation of a multi-band 5G NR system with photonic-assisted RF amplification (PAA). The approach takes advantage of a novel PAA technique, based on RoF technology and four-wave mixing effect, that allows straightforward integration to the transport networks. Experimental results demonstrate iv uniform and stable 15 dB wideband gain for Long Term Evolution (LTE) and three 5G signals, distributed in the frequency range from 780 MHz to 26 GHz and coexisting in the mobile fronthaul. The obtained digital performance has efficiently met the Third-Generation Partnership Project (3GPP) requirements, demonstrating the applicability of the proposed approach for using fiber-optic links to distribute and jointly amplify LTE and 5G signals in the optical domain.AgĂȘncia 1Este trabalho apresenta soluçÔes de rĂĄdio sobre fibra (RoF) para aplicaçÔes em redes sem fio de quinta geração (5G), e inclui quatro contribuiçÔes principais. A primeira delas refere-se Ă  proposta e investigação de uma tĂ©cnica de RoF baseada no modulador eletroĂłptico de braço duplo, dual-drive Mach-Zehnder (DD-MZM), para a transmissĂŁo simultĂąnea de sinais de radiofrequĂȘncia (RF) em bandas previstas para redes 5G. Resultados experimentais demonstram que o uso do DD-MZM favorece a ausĂȘncia de interferĂȘncia entre os sinais de RF transmitidos. A segunda contribuição trata da integração de um transceptor de RF, desenvolvido para aplicaçÔes 5G e apto a prover a forma de onda conhecida como generalized frequency division multiplexing (GFDM), em uma rede Ăłptica passiva (PON) ao utilizar RoF e multiplexação por divisĂŁo de comprimento de onda (WDM). A arquitetura proposta permite transportar, na mesma infraestrutura de rede, sinais em banda base e de radiofrequĂȘncia nas faixas do espectro candidatas para 5G. A prova de conceito inclui a distribuição conjunta de trĂȘs tipos de sinais: um sinal GFDM na banda de 700 MHz, proveniente do transceptor desenvolvido; um sinal digital na frequĂȘncia de 26 GHz, assumindo a faixa de ondas milimĂ©tricas; sinais em banda base provenientes de uma PON dedicada ao serviço de Internet. Resultados experimentais demonstram o desempenho do transceptor de RF ao utilizar a referida arquitetura para distribuir sinais GFDM, alĂ©m de taxas de transmissĂŁo de dados da ordem de Gbit/s na faixa de 26 GHz. A terceira contribuição corresponde Ă  implementação de um sistema fibra/rĂĄdio potencial para redes 5G, operando inclusive com o padrĂŁo ―5G New Radio (5G NR)‖ nas faixas de micro-ondas e ondas milimĂ©tricas. Tal sistema Ă© capaz de prover macro cĂ©lulas na banda de 700 MHz para aplicaçÔes de longo alcance e/ou rurais, utilizando sinais GFDM ou filtered orthogonal frequency division multiplexing (F-OFDM), assim como femto cĂ©lulas na banda de 26 GHz, destinada a altas taxas de transmissĂŁo de dados para comunicaçÔes de curto alcance. Resultados experimentais demonstram a aplicabilidade da solução proposta para redes 5G, alĂ©m da viabilidade de utilizar redes Ăłpticas pertencentes a provedores de Internet para favorecer sistemas de nova geração. Por fim, a quarta contribuição trata da implementação de um sistema 5G NR multibanda, assistido por amplificação de RF no domĂ­nio Ăłptico. Esse sistema faz uso de um novo mĂ©todo de amplificação, baseado no efeito nĂŁo linear da mistura de quatro ondas, que vi permite integração direta em redes de transporte envolvendo rĂĄdio sobre fibra. Resultados experimentais demonstram ganho de RF igual a 15 dB em uma ampla faixa de frequĂȘncias (700 MHz atĂ© 26 GHz), atendendo simultaneamente tecnologias de quarta e quinta geração. O desempenho digital obtido atendeu aos requisitos estabelecidos pela 3GPP (Third-Generation Partnership Project), indicando a aplicabilidade da solução em questĂŁo para distribuir e conjuntamente amplificar sinais de RF em enlaces de fibra Ăłptica

    A Survey of Air-to-Ground Propagation Channel Modeling for Unmanned Aerial Vehicles

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    In recent years, there has been a dramatic increase in the use of unmanned aerial vehicles (UAVs), particularly for small UAVs, due to their affordable prices, ease of availability, and ease of operability. Existing and future applications of UAVs include remote surveillance and monitoring, relief operations, package delivery, and communication backhaul infrastructure. Additionally, UAVs are envisioned as an important component of 5G wireless technology and beyond. The unique application scenarios for UAVs necessitate accurate air-to-ground (AG) propagation channel models for designing and evaluating UAV communication links for control/non-payload as well as payload data transmissions. These AG propagation models have not been investigated in detail when compared to terrestrial propagation models. In this paper, a comprehensive survey is provided on available AG channel measurement campaigns, large and small scale fading channel models, their limitations, and future research directions for UAV communication scenarios

    Emerging Communication Technologies (ECT) Phase 4 Report

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    The Emerging Communication Technology (ECT) project investigated three First Mile communication technologies in support of NASA s Crew Exploration Vehicle (CEV), Advanced Range Technology Working Group (ARTWG), and the Advanced Spaceport Technology Working Group (ASTWG). These First Mile technologies have the purpose of interconnecting mobile users with existing Range Communication infrastructures on a 24/7 basis. ECT is a continuation of the Range Information System Management (RISM) task started in 2002. This is the fourth year of the project

    Ultra-low power, low-voltage transmitter at ISM band for short range transceivers

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    Tezin basılısı Ä°stanbul ƞehir Üniversitesi KĂŒtĂŒphanesi'ndedir.The increasing demand for technology to be used in every aspect of our lives has led the way to many new applications and communication standards. WSN and BAN are some of the new examples that utilize electronic circuit design in the form of very small sensors to perform their applications. They consist of small sensor nodes and have applications ranging from entertainment to medicine. Requirements such as decreasing the area and the power consumption help to have longer-lasting batteries and smaller devices. The standard paves the way for the devices from diïŹ€erent vendors to communicate with each other, and that motivates us to make designs as compatible with the standard as it can be. In this thesis, an ultra-low power high eïŹƒcient transmitter with a small area working at 2.4 GHz have been designed for BAN applications. A study on the system-view perspective is important in optimizing the area and power since the transmitter architecture can change the circuit design. From a circuit design perspective, seeking to decrease power consumption means thinking of new techniques to implement the same function or a new system. Inspired by new trends, this research presents a design solution to the previously mentioned problem and hopefully, after fabrication, the measured results will match the simulated results to prove the validity of the design.Declaration of Authorship ii Abstract iv Öz v Acknowledgments vii List of Figures x List of Tables xiii Abbreviations xiv 1 Introduction 1 1.1 Background and Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.2 Communication Concepts . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.2.1 Digital Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1.2.2 Unwanted Power Limitations . . . . . . . . . . . . . . . . . . . . . 3 1.2.3 Multiple Access Techniques . . . . . . . . . . . . . . . . . . . . . . 3 1.3 Transmitter System Level SpeciïŹcations . . . . . . . . . . . . . . . . . . . 4 1.3.1 Low Power Wireless Standards . . . . . . . . . . . . . . . . . . . . 4 1.4 Low-Power Wireless Transceiver systems . . . . . . . . . . . . . . . . . . . 6 1.4.1 Survey of the previous work . . . . . . . . . . . . . . . . . . . . . . 7 1.4.2 The Designed Transmitter System . . . . . . . . . . . . . . . . . . 8 1.5 Ultra-Low Power Transmitters Performance Metrics . . . . . . . . . . . . 9 1.6 Thesis Contribution and Outline . . . . . . . . . . . . . . . . . . . . . . . 10 2 Circuit Design for The Transmitter 11 2.1 Technology Characterization and Modeling for Low-Power Designs . . . 11 2.1.1 Passive Components modeling . . . . . . . . . . . . . . . . . . . . 11 2.1.2 Active Components Modeling . . . . . . . . . . . . . . . . . . . . . 13 2.1.3 MOS Transistor Sub-threshold Modeling . . . . . . . . . . . . . . 13 2.1.4 MOS Transistor Simulation-Based Modeling . . . . . . . . . . . . . 14 2.2 Low-Voltage Low-Power Analog and RF Design Principles . . . . . . . . . 17 2.2.1 Separate Gate Biasing of The Inverter . . . . . . . . . . . . . . . . 17 2.2.2 Body Biasing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 2.3 Low-Voltage Analog Mixed Biasing Circuit Designs . . . . . . . . . . . . . 18 2.3.1 DAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 2.3.2 Operational AmpliïŹer Design . . . . . . . . . . . . . . . . . . . . . 19 2.4 Crystal Oscillator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 2.4.1 The MEMS Crystal . . . . . . . . . . . . . . . . . . . . . . . . . . 22 2.4.2 Crystal Oscillator Topologies . . . . . . . . . . . . . . . . . . . . . 23 2.4.3 Design of The CMOS Crystal Oscillator . . . . . . . . . . . . . . . 26 2.5 Pre-Driver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 2.6 OOK Modulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 2.7 BPSK Modulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 2.8 Digital Control of the Modulators . . . . . . . . . . . . . . . . . . . . . . . 35 2.9 Power AmpliïŹer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 2.9.1 ULP PA Topologies Survey . . . . . . . . . . . . . . . . . . . . . . 38 2.9.2 The Push-Pull PA Design Methodology . . . . . . . . . . . . . . . 41 2.10 Transmit/Receive (T/R) Switch . . . . . . . . . . . . . . . . . . . . . . . 43 2.10.1 T/R Switch Topologies . . . . . . . . . . . . . . . . . . . . . . . . . 43 2.10.2 Suggested Low-Area Low-Voltage RF Switch . . . . . . . . . . . . 46 3 Transmitter Integration and Final Results 48 3.1 Transmitter Simulations . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 3.2 Transmitter Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 3.3 Results Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 3.4 Results Comparison . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 4 Conclusions 59 4.1 Thesis Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 4.2 Future Work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 A Bond Wire Parasitic Modeling 61 B Crystal Oscillator With Parasitic EïŹ€ects 67 B.1 Simulation of FBAR with Parasitic EïŹ€ects . . . . . . . . . . . . . . . . . 67 B.2 Root Locus Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70 Bibliography 7
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