158 research outputs found

    Self-Calibrated, Low-Jitter and Low-Reference-Spur Injection-Locked Clock Multipliers

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    Department of Electrical EngineeringThis dissertation focuses primarily on the design of calibrators for the injection-locked clock multiplier (ILCM). ILCMs have advantage to achieve an excellent jitter performance at low cost, in terms of area and power consumption. The wide loop bandwidth (BW) of the injection technique could reject the noise of voltage-controlled oscillator (VCO), making it thus suitable for the rejection of poor noise of a ring-VCO and a high frequency LC-VCO. However, it is difficult to use without calibrators because of its sensitiveness in process-voltage-temperature (PVT) variations. In Chapter 2, conventional frequency calibrators are introduced and discussed. This dissertation introduces two types of calibrators for low-power high-frequency LC-VCO-based ILFMs in Chapter 3 and Chapter 4 and high-performance ring-VCO-based ILCM in Chapter 5. First, Chapter 3 presents a low power and compact area LC-tank-based frequency multiplier. In the proposed architecture, the input signals have a pulsed waveform that involves many high-order harmonics. Using an LC-tank that amplifies only the target harmonic component, while suppressing others, the output signal at the target frequency can be obtained. Since the core current flows for a very short duration, due to the pulsed input signals, the average power consumption can be dramatically reduced. Effective removal of spurious tones due to the damping of the signal is achieved using a limiting amplifier. In this work, a prototype frequency tripler using the proposed architecture was designed in a 65 nm CMOS process. The power consumption was 950 ??W, and the active area was 0.08 mm2. At a 3.12 GHz frequency, the phase noise degradation with respect to the theoretical bound was less than 0.5 dB. Second, Chapter 4 presents an ultra-low-phase-noise ILFM for millimeter wave (mm-wave) fifth-generation (5G) transceivers. Using an ultra-low-power frequency-tracking loop (FTL), the proposed ILFM is able to correct the frequency drifts of the quadrature voltage-controlled oscillator of the ILFM in a real-time fashion. Since the FTL is monitoring the averages of phase deviations rather than detecting or sampling the instantaneous values, it requires only 600??W to continue to calibrate the ILFM that generates an mm-wave signal with an output frequency from 27 to 30 GHz. The proposed ILFM was fabricated in a 65-nm CMOS process. The 10-MHz phase noise of the 29.25-GHz output signal was ???129.7 dBc/Hz, and its variations across temperatures and supply voltages were less than 2 dB. The integrated phase noise from 1 kHz to 100 MHz and the rms jitter were???39.1 dBc and 86 fs, respectively. Third, Chapter 5 presents a low-jitter, low-reference-spur ring voltage-controlled oscillator (ring VCO)-based ILCM. Since the proposed triple-point frequency/phase/slope calibrator (TP-FPSC) can accurately remove the three root causes of the frequency errors of ILCMs (i.e., frequency drift, phase offset, and slope modulation), the ILCM of this work is able to achieve a low-level reference spur. In addition, the calibrating loop for the frequency drift of the TP-FPSC offers an additional suppression to the in-band phase noise of the output signal. This capability of the TP-FPSC and the naturally wide bandwidth of the injection-locking mechanism allows the ILCM to achieve a very low RMS jitter. The ILCM was fabricated in a 65-nm CMOS technology. The measured reference spur and RMS jitter were ???72 dBc and 140 fs, respectively, both of which are the best among the state-of-the-art ILCMs. The active silicon area was 0.055 mm2, and the power consumption was 11.0 mW.clos

    External Cavity Mode-locked Semiconductor Lasers For The Generation Of Ultra-low Noise Multi-gigahertz Frequency Combs And Applications In Multi-heterodyne Detection Of Arbitrary Optical Waveforms

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    The construction and characterization of ultra-low noise semiconductor-based mode-locked lasers as frequency comb sources with multi-gigahertz combline-to-combline spacing is studied in this dissertation. Several different systems were built and characterized. The first of these systems includes a novel mode-locking mechanism based on phase modulation and periodic spectral filtering. This mode-locked laser design uses the same intra-cavity elements for both mode-locking and frequency stabilization to an intra-cavity, 1,000 Finesse, Fabry-Pérot Etalon (FPE). On a separate effort, a mode-locked laser based on a Slab-Coupled Optical Waveguide Amplifier (SCOWA) was built. This system generates a pulse-train with residual timing jitter o

    Noise, Stability, and Linewidth Performance of 10-GHz Optical Frequency Combs Generated from the Nested Cavity Architecture

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    Optical frequency combs with wide mode spacing and low timing jitter are relied upon for both time domain and frequency domain applications. It has been previously demonstrated that surrounding a low-Q semiconductor laser chip with a long external fiber cavity and inserting a high finesse Fabry–Pérot etalon into this cavity can produce a mode-locked laser with the desired high repetition rate and narrow optical mode linewidths which are of benefit to applications like photonic analog-to-digital conversion and astronomical spectrograph calibration. With this nested cavity architecture, the quality factor of the resonator is effectively determined by the product of the individual quality factors of the long fiber cavity and the short etalon cavity. Passive cavity Q and intracavity power both influence mode-locked laser mode linewidth, optical frequency stability, and the phase noise of the photodetected output. The nested cavity architecture has been demonstrated at 10-GHz mode spacing a few times with increasing etalon finesse and once with a high saturation power semiconductor gain medium to increase intracavity power. No one system has been fully characterized for long term optical frequency stability, phase noise and timing jitter, and optical mode linewidth. As a result, the trade-offs involved with advancing any one element (e.g. increasing cavity Q by adding fiber length and maintaining a broad spectral region of low dispersion for broad-bandwidth operation) have not been fully examined. In this work, three cavity elements are identified for study to influence cavity Q, effective noise spur suppression, and intracavity power, and the trade-offs of pushing those parameters to new limits are experimentally demonstrated. In the process, we also demonstrate nested cavity systems with fractional frequency instability on the order of 10-13, timing jitter as low as 20 fs, and Hz-level linewidths

    Low power CMOS IC, biosensor and wireless power transfer techniques for wireless sensor network application

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    The emerging field of wireless sensor network (WSN) is receiving great attention due to the interest in healthcare. Traditional battery-powered devices suffer from large size, weight and secondary replacement surgery after the battery life-time which is often not desired, especially for an implantable application. Thus an energy harvesting method needs to be investigated. In addition to energy harvesting, the sensor network needs to be low power to extend the wireless power transfer distance and meet the regulation on RF power exposed to human tissue (specific absorption ratio). Also, miniature sensor integration is another challenge since most of the commercial sensors have rigid form or have a bulky size. The objective of this thesis is to provide solutions to the aforementioned challenges

    Lithium niobate RF-MEMS oscillators for IoT, 5G and beyond

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    This dissertation focuses on the design and implementation of lithium niobate (LiNbO3) radiofrequency microelectromechanical (RF-MEMS) oscillators for internet-of-things (IoT), 5G and beyond. The dissertation focuses on solving two main problems found nowadays in most of the published works: the narrow tuning range and the low operating frequency (sub 3 GHz) acoustic oscillators currently deliver. The work introduced here enables wideband voltage-controlled MEMS oscillators (VCMOs) needed for emerging applications in IoT. Moreover, it enables multi-GHz (above 8 GHz) RF-MEMS oscillators through harnessing over mode resonances for 5G and beyond. LiNbO3 resonators characterized by high-quality factor (Q), high electromechanical coupling (kt2), and high figure-of-merit (FoMRES= Q kt2) are crucial for building the envisioned high-performance oscillators. Those oscillators can be enabled with lower power consumption, wider tuning ranges, and a higher frequency of oscillation when compared to other state-of-the-art (SoA) RF-MEMS oscillators. Tackling the tuning range issue, the first VCMO based on the heterogeneous integration of a high Q LiNbO3 RF-MEMS resonator and complementary metal-oxide semiconductor (CMOS) is demonstrated in this dissertation. A LiNbO3 resonator array with a series resonance of 171.1 MHz, a Q of 410, and a kt2 of 12.7% is adopted, while the TSMC 65 nm RF LP CMOS technology is used to implement the active circuitry with an active area of 220×70 µm2. Frequency tuning of the VCMO is achieved by programming a binary-weighted digital capacitor bank and a varactor that are both connected in series to the resonator. The measured best phase noise performances of the VCMO are -72 and -153 dBc/Hz at 1 kHz and 10 MHz offsets from 178.23 and 175.83 MHz carriers, respectively. The VCMO consumes a direct current (DC) of 60 µA from a 1.2 V supply while realizing a tuning range of 2.4 MHz (~ 1.4% tuning range). Such VCMOs can be applied to enable ultralow-power, low phase noise, and wideband RF synthesis for emerging applications in IoT. Moreover, the first VCMO based on LiNbO3 lateral overtone bulk acoustic resonator (LOBAR) is demonstrated in this dissertation. The LOBAR excites over 30 resonant modes in the range of 100 to 800 MHz with a frequency spacing of 20 MHz. The VCMO consists of a LOBAR in a closed-loop with two amplification stages and a varactor-embedded tunable LC tank. By the bias voltage applied to the varactor, the tank can be tuned to change the closed-loop gain and phase responses of the oscillator so that Barkhausen’s conditions are satisfied for the targeted resonant mode. The tank is designed to allow the proposed VCMO to lock to any of the ten overtones ranging from 300 to 500 MHz. These ten tones are characterized by average Qs of 2100, kt2 of 1.5%, FoMRES of 31.5 enabling low phase noise, and low-power oscillators crucial for IoT. Owing to the high Qs of the LiNbO3 LOBAR, the measured VCMO shows a close-in phase noise of -100 dBc/Hz at 1 kHz offset from a 300 MHz carrier and a noise floor of -153 dBc/Hz while consuming 9 mW. With further optimization, this VCMO can lead to direct RF synthesis for ultra-low-power transceivers in multi-mode IoT nodes. Tackling the multi-GHz operation problem, the first Ku-band RF-MEMS oscillator utilizing a third antisymmetric overtone (A3) in a LiNbO3 resonator is presented in the dissertation. Quarter-wave resonators are used to satisfy Barkhausen’s oscillation conditions for the 3rd overtone while suppressing the fundamental and higher-order resonances. The oscillator achieves measured phase noise of -70 and -111 dBc/Hz at 1 kHz and 100 kHz offsets from a 12.9 GHz carrier while consuming 20 mW of dc power. The oscillator achieves a FoMOSC of 200 dB at 100 kHz offset. The achieved oscillation frequency is the highest reported to date for a MEMS oscillator. In addition, this dissertation introduces the first X-band RF-MEMS oscillator built using CMOS technology. The oscillator consists of an acoustic resonator in a closed loop with cascaded RF tuned amplifiers (TAs) built on TSMC RF GP 65 nm CMOS. The TAs bandpass response, set by on-chip inductors, satisfies Barkhausen's oscillation conditions for A3 only. Two circuit variations are implemented. The first is an 8.6 GHz standalone oscillator with a source-follower buffer for direct 50 Ω-based measurements. The second is an oscillator-divider chain using an on-chip 3-stage divide-by-2 frequency divider for a ~1.1 GHz output. The standalone oscillator achieves measured phase noise of -56, -113, and -135 dBc/Hz at 1 kHz, 100 kHz, and 1 MHz offsets from an 8.6 GHz output while consuming 10.2 mW of dc power. The oscillator also attains a FoMOSC of 201.6 dB at 100 kHz offset, surpassing the SoA electromagnetic (EM) and RF-MEMS based oscillators. The oscillator-divider chain produces a phase noise of -69.4 and -147 dBc/Hz at 1 kHz and 1 MHz offsets from a 1075 MHz output while consuming 12 mW of dc power. Its phase noise performance also surpasses the SoA L-band phase-locked loops (PLLs). The demonstrated performance shows the strong potential of microwave acoustic oscillators for 5G frequency synthesis and beyond. This work will enable low-power 5G transceivers featuring high speed, high sensitivity, and high selectivity in small form factors

    Multi-Loop-Ring-Oscillator Design and Analysis for Sub-Micron CMOS

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    Ring oscillators provide a central role in timing circuits for today?s mobile devices and desktop computers. Increased integration in these devices exacerbates switching noise on the supply, necessitating improved supply resilience. Furthermore, reduced voltage headroom in submicron technologies limits the number of stacked transistors available in a delay cell. Hence, conventional single-loop oscillators offer relatively few design options to achieve desired specifications, such as supply rejection. Existing state-of-the-art supply-rejection- enhancement methods include actively regulating the supply with an LDO, employing a fully differential or current-starved delay cell, using a hi-Z voltage-to-current converter, or compensating/calibrating the delay cell. Multiloop ring oscillators (MROs) offer an additional solution because by employing a more complex ring-connection structure and associated delay cell, the designer obtains an additional degree of freedom to meet the desired specifications. Designing these more complex multiloop structures to start reliably and achieve the desired performance requires a systematic analysis procedure, which we attack on two fronts: (1) a generalized delay-cell viewpoint of the MRO structure to assist in both analysis and circuit layout, and (2) a survey of phase-noise analysis to provide a bank of methods to analyze MRO phase noise. We distill the salient phase-noise-analysis concepts/key equations previously developed to facilitate MRO and other non-conventional oscillator analysis. Furthermore, our proposed analysis framework demonstrates that all these methods boil down to obtaining three things: (1) noise modulation function (NMF), (2) noise transfer function (NTF), and (3) current-controlled-oscillator gain (KICO). As a case study, we detail the design, analysis, and measurement of a proposed multiloop ring oscillator structure that provides improved power-supply isolation (more than 20dB increase in supply rejection over a conventional-oscillator control case fabricated on the same test chip). Applying our general multi-loop-oscillator framework to this proposed MRO circuit leads both to design-oriented expressions for the oscillation frequency and supply rejection as well as to an efficient layout technique facilitating cross-coupling for improved quadrature accuracy and systematic, substantially simplified layout effort

    Optical Microwave Signal Generation for Data Transmission in Optical Networks

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    The massive growth of telecommunication services and the increasing global data traffic boost the development, implementation, and integration of different networks for data transmission. An example of this development is the optical fiber networks, responsible today for the inter-continental connection through long-distance links and high transfer rates. The optical networks, as well as the networks supported by other transmission media, use electrical signals at specific frequencies for the synchronization of the network elements. The quality of these signals is usually determined in terms of phase noise. Due to the major impact of the phase noise over the system performance, its value should be minimized. The research work presented in this document describes the design and implementation of an optoelectronic system for the microwave signal generation using a vertical-cavity surface-emitting laser (VCSEL) and its integration into an optical data transmission system. Considering that the proposed system incorporates a directly modulated VCSEL, a theoretical and experimental characterization was developed based on the laser rate equations, dynamic and static measurements, and an equivalent electrical model of the active region. This procedure made possible the extraction of some VCSEL intrinsic parameters, as well as the validation and simulation of the VCSEL performance under specific modulation conditions. The VCSEL emits in C-band, this wavelength was selected because it is used in long-haul links. The proposed system is a self-initiated oscillation system caused by internal noise sources, which includes a VCSEL modulated in large signal to generate optical pulses (gain switching). The optical pulses, and the optical frequency comb associated, generate in electrical domain simultaneously a fundamental frequency (determined by a band-pass filter) and several harmonics. The phase noise measured at 10 kHz from the carrier at 1.25 GHz was -127.8 dBc/Hz, and it is the lowest value reported in the literature for this frequency and architecture. Both the jitter and optical pulse width were determined when different resonant cavities and polarization currents were employed. The lowest pulse duration was 85 ps and was achieved when the fundamental frequency was 2.5 GHz. As for the optical frequency comb, it was demonstrated that its flatness depends on the electrical modulation conditions. The flattest profiles are obtained when the fundamental frequency is higher than the VCSEL relaxation frequency. Both the electrical and the optical output of the system were integrated into an optical transmitter. The electrical signal provides the synchronization of the data generating equipment, whereas the optical pulses are employed as an optical carrier. Data transmissions at 155.52 Mb/s, 622.08 Mb/s and 1.25 Gb/s were experimentally validated. It was demonstrated that the fundamental frequency and harmonics could be extracted from the optical data signal transmitted by a band-pass filter. It was also experimentally proved that the pulsed return-to-zero (RZ) transmitter at 1.25 Gb/s, achieves bit error rates (BER) lower than 10910^{-9} when the optical power at the receiver is higher than -33 dBm.La masificación de los servicios de telecomunicaciones y el creciente tráfico global de datos han impulsado el desarrollo, despliegue e integración de diferentes redes para la transmisión de datos. Un ejemplo de este despliegue son las redes de fibra óptica, responsables en la actualidad de la interconexión de los continentes a través de enlaces de grandes longitudes y altas tasas de transferencia. Las redes ópticas, al igual que las redes soportadas por otros medios de transmisión, utilizan señales eléctricas a frecuencias específicas para la sincronización de los elementos de red. La calidad de estas señales es determinante en el desempeño general del sistema, razón por la que su ruido de fase debe ser lo más pequeño posible. El trabajo de investigación presentado en este documento describe el diseño e implementación de un sistema optoelectrónico para la generación de señales microondas utilizando diodos láser de cavidad vertical (VCSEL) y su integración en un sistema de transmisión de datos óptico. Teniendo en cuenta que el sistema propuesto incorpora un láser VCSEL modulado directamente, se desarrolló una caracterización teórico-experimental basada en las ecuaciones de evolución del láser, mediciones dinámicas y estáticas, y un modelo eléctrico equivalente de la región activa. Este procedimiento posibilitó la extracción de algunos parámetros intrínsecos del VCSEL, al igual que la validación y simulación de su desempeño bajo diferentes condiciones de modulación. El VCSEL utilizado emite en banda C y fue seleccionado considerando que esta banda es comúnmente utilizada en enlaces de largo alcance. El sistema propuesto consiste en un lazo cerrado que inicia la oscilación gracias a las fuentes de ruido de los componentes y modula el VCSEL en gran señal para generar pulsos ópticos (conmutación de ganancia). Estos pulsos ópticos, que en el dominio de la frecuencia corresponden a un peine de frecuencia óptico, son detectados para generar simultáneamente una frecuencia fundamental (determinada por un filtro pasa banda) y varios armónicos. El ruido de fase medido a 10 kHz de la portadora a 1.25 GHz fue -127.8 dBc/Hz, y es el valor más bajo reportado en la literatura para esta frecuencia y arquitectura. Tanto la fluctuación de fase (jitter) y el ancho de los pulsos ópticos fueron determinados cuando diferentes cavidades resonantes y corrientes de polarización fueron empleadas. La duración de pulso más baja fue 85 ps y se obtuvo cuando la frecuencia fundamental del sistema era 2.5 GHz. En cuanto al peine de frecuencia óptico, se demostró que su planitud (flatness) depende de las condiciones eléctricas de modulación y que los perfiles más planos se obtienen cuando la frecuencia fundamental es superior a la frecuencia de relajación del VCSEL. Tanto la salida eléctrica como la salida óptica del sistema fueron integradas en un transmisor óptico. La señal eléctrica permite la sincronización de los equipos encargados de generar los datos, mientras que los pulsos ópticos son utilizados como portadora óptica. La transmisión de datos a 155.52 Mb/s, 622.08 Mb/s y 1.25 Gb/s fue validada experimentalmente. Se demostró que la frecuencia fundamental y los armónicos pueden ser extraídos de la señal óptica de datos transmitida mediante un filtro pasa banda. También se comprobó experimentalmente que el transmisor de datos pulsados con retorno a cero (RZ) a 1.25 Gb/s, logra tasas de error de bit (BER) menores a 10-9 cuando la potencia óptica en el receptor es mayor a -33 dBm.Gobernación de NariñoBPIN 2013000100092Doctorad

    Multi-Loop-Ring-Oscillator Design and Analysis for Sub-Micron CMOS

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    Ring oscillators provide a central role in timing circuits for today?s mobile devices and desktop computers. Increased integration in these devices exacerbates switching noise on the supply, necessitating improved supply resilience. Furthermore, reduced voltage headroom in submicron technologies limits the number of stacked transistors available in a delay cell. Hence, conventional single-loop oscillators offer relatively few design options to achieve desired specifications, such as supply rejection. Existing state-of-the-art supply-rejection- enhancement methods include actively regulating the supply with an LDO, employing a fully differential or current-starved delay cell, using a hi-Z voltage-to-current converter, or compensating/calibrating the delay cell. Multiloop ring oscillators (MROs) offer an additional solution because by employing a more complex ring-connection structure and associated delay cell, the designer obtains an additional degree of freedom to meet the desired specifications. Designing these more complex multiloop structures to start reliably and achieve the desired performance requires a systematic analysis procedure, which we attack on two fronts: (1) a generalized delay-cell viewpoint of the MRO structure to assist in both analysis and circuit layout, and (2) a survey of phase-noise analysis to provide a bank of methods to analyze MRO phase noise. We distill the salient phase-noise-analysis concepts/key equations previously developed to facilitate MRO and other non-conventional oscillator analysis. Furthermore, our proposed analysis framework demonstrates that all these methods boil down to obtaining three things: (1) noise modulation function (NMF), (2) noise transfer function (NTF), and (3) current-controlled-oscillator gain (KICO). As a case study, we detail the design, analysis, and measurement of a proposed multiloop ring oscillator structure that provides improved power-supply isolation (more than 20dB increase in supply rejection over a conventional-oscillator control case fabricated on the same test chip). Applying our general multi-loop-oscillator framework to this proposed MRO circuit leads both to design-oriented expressions for the oscillation frequency and supply rejection as well as to an efficient layout technique facilitating cross-coupling for improved quadrature accuracy and systematic, substantially simplified layout effort

    ENABLING HARDWARE TECHNOLOGIES FOR AUTONOMY IN TINY ROBOTS: CONTROL, INTEGRATION, ACTUATION

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    The last two decades have seen many exciting examples of tiny robots from a few cm3 to less than one cm3. Although individually limited, a large group of these robots has the potential to work cooperatively and accomplish complex tasks. Two examples from nature that exhibit this type of cooperation are ant and bee colonies. They have the potential to assist in applications like search and rescue, military scouting, infrastructure and equipment monitoring, nano-manufacture, and possibly medicine. Most of these applications require the high level of autonomy that has been demonstrated by large robotic platforms, such as the iRobot and Honda ASIMO. However, when robot size shrinks down, current approaches to achieve the necessary functions are no longer valid. This work focused on challenges associated with the electronics and fabrication. We addressed three major technical hurdles inherent to current approaches: 1) difficulty of compact integration; 2) need for real-time and power-efficient computations; 3) unavailability of commercial tiny actuators and motion mechanisms. The aim of this work was to provide enabling hardware technologies to achieve autonomy in tiny robots. We proposed a decentralized application-specific integrated circuit (ASIC) where each component is responsible for its own operation and autonomy to the greatest extent possible. The ASIC consists of electronics modules for the fundamental functions required to fulfill the desired autonomy: actuation, control, power supply, and sensing. The actuators and mechanisms could potentially be post-fabricated on the ASIC directly. This design makes for a modular architecture. The following components were shown to work in physical implementations or simulations: 1) a tunable motion controller for ultralow frequency actuation; 2) a nonvolatile memory and programming circuit to achieve automatic and one-time programming; 3) a high-voltage circuit with the highest reported breakdown voltage in standard 0.5 μm CMOS; 4) thermal actuators fabricated using CMOS compatible process; 5) a low-power mixed-signal computational architecture for robotic dynamics simulator; 6) a frequency-boost technique to achieve low jitter in ring oscillators. These contributions will be generally enabling for other systems with strict size and power constraints such as wireless sensor nodes

    Active Backscattering Positioning System Using Innovative Harmonic Oscillator Tags for Future Internet of Things: Theory and Experiments

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    RÉSUMÉ D'ici 2020, l'Internet des objets (IoT) permettra probablement de créer 25 milliards d'objets connectés, 44 ZB de données et de débloquer 11 000 milliards de dollars d’opportunités commerciales. Par conséquent, ce sujet a suscité d’énormes intérêts de recherche dans le monde académique entier. L'une des technologies clés pour l'IoT concerne le positionnement physique intérieur précis. Le principal objectif dans ce domaine est le développement d'un système de positionnement intérieur avec une grande précision, une haute résolution, un fonctionnement à plusieurs cibles, un faible coût, un faible encombrement et une faible consommation d'énergie. Le système de positionnement intérieur conventionnel basé sur les technologies de Wi-Fi ou d'identification par radiofréquence (RFID) ne peut répondre à ces exigences. Principalement parce que leur appareil et leur signal ne sont pas conçus spécialement pour atteindre les objectifs visés. Les chercheurs ont découvert qu'en mettant en oeuvre de différents types de modulation sur les étiquettes, le radar à onde continue (CW) et ses dérivés deviennent des solutions prometteuses. Les activités de recherche présentées dans cette thèse sont menées dans le but de développer des systèmes de positionnement en intérieur bidimensionnel (2-D) à plusieurs cibles basées sur des étiquettes actives à rétrodiffusion harmonique avec une technique à onde continue modulée en fréquence (FMCW). Les contributions de cette thèse peuvent être résumées comme suit: Tout d'abord, la conception d'un circuit actif harmonique, plus spécifiquement une classe d'oscillateurs harmoniques innovants utilisée comme composant central des étiquettes actives dans notre système, implique une méthodologie de conception de signal de grande taille et des installations de caractérisation. L’analyseur de réseau à grand signal (LSNA) est un instrument émergent basé sur les fondements théoriques du cadre de distorsion polyharmonique (PHD). Bien qu'ils soient disponibles dans le commerce depuis 2008, des organismes de normalisation et de recherche tels que l’Institut national des normes et de la technologie (NIST) des États-Unis travaillent toujours à la mise au point d'un standard largement reconnu permettant d'évaluer et de comparer leurs performances. Dans ce travail, un artefact de génération multi-harmonique pour la vérification LSNA est développé. C'est un dispositif actif capable de générer les 5 premières harmoniques d'un signal d'entrée avec une réponse ultra-stables en amplitude et en phase, quelle que soit la variation de l'impédance de la charge.----------ABSTRACT By 2020, the internet of things (IoT) will probably enable 25 billion connected objects, create 44 ZB data and unlock 11 trillion US dollar business opportunities. Therefore, this topic has been attracting tremendous research interests in the entire academic world. One of the key enabling technologies for IoT is concerned with accurate indoor physical positioning. The development of such an indoor positioning system with high accuracy, high resolution, multitarget operation, low cost, small footprint, and low power consumption is the major objective in this area. The conventional indoor positioning system based on WiFi or radiofrequency identification (RFID) technology cannot fulfill these requirements mainly because their device and signal are not purposely designed for achieving the targeted goals. Researchers have found that by implementing different types of modulation on the tags, continuous-wave (CW) radar and its derivatives become promising solutions. The research activities presented in this Ph.D. thesis are carried out towards the goal of developing multitarget two-dimensional (2-D) indoor positioning systems based on harmonic backscattering active tags together with a frequency-modulated continuous-wave (FMCW) technique. Research contributions of this thesis can be summarized as follows: First of all, the design of a harmonic active circuit, more specifically, a class of innovative harmonic oscillators used as the core component of active tags in our system, involves a large signal design methodology and characterization facilities. The large signal network analyzer (LSNA) is an emerging instrument based on the theoretical foundation for the Poly-Harmonic Distortion (PHD) framework. Although they have been commercially available since 2008, standard and research organizations such as the National Institute of Standards and Technology (NIST) of the US are still working towards a widely-recognized standard to evaluate and cross-reference their performances. In this work, a multi-harmonic generation artifact for LSNA verification is developed. It is an active device that can generate the first 5 harmonics of an input signal with ultra-stable amplitude and phase response regardless of the load impedance variation
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