1,330 research outputs found

    Two Improved Cancellation Techniques for Direct-Conversion Receivers

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    Millimeter-Wave MMICs and Applications

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    As device technology improves, interest in the millimeter-wave band grows. Wireless communication systems migrate to higher frequencies, millimeter-wave radars and passive sensors find new solid-state implementations that promise improved performance, and entirely new applications in the millimeter-wave band become feasible. The circuit or system designer is faced with a new and unique set of challenges and constraints to deal with in order to use this portion of the spectrum successfully. In particular, the advantages of monolithic integration become increasingly important. This thesis presents many new developments in Monolithic Millimeter-Wave Integrated Circuits (MMICs), both the chips themselves and systems that use them. It begins with an overview of the various applications of millimeter waves, including a discussion of specific projects that the author is involved in and why many of them demand a MMIC implementation. In the subsequent chapters, new MMIC chips are described in detail, as is the role they play in real-world projects. Multi-chip modules are also presented with specific attention given to the practical details of MMIC packaging and multi-chip integration. The thesis concludes with a summary of the works presented thus far and their overall impact on the field of millimeter-wave engineering.</p

    RF Measurement Techniques

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    For the characterization of components, systems and signals in the range of microwave and radio-frequencies (RF) specific equipment and dedicated measurement instruments are used. In this article the fundamentals of RF signal processing and measurement techniques are discussed. It gives complementary background information for the introduction to RF Measurement Techniques and the Practical RF Course, which are part of the Advanced Accelerator Physics training program of the CERN Accelerator School (CAS) and have also been presented at the CAS 2018 Special Topic Course in Beam Instrumentation.Comment: 54 pages, contribution to the CAS - CERN Accelerator School: Beam Instrumentation, 2-15 June 2018, Tuusula, Finlan

    Embedded vector measurement of RF/microwave circuits in LTCC technology

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    As the number of wireless systems and standards continues to increase, RF hardware re-use is becoming more and more important to reduce cost and size and eliminate unnecessary component redundancy. One way of maximizing RF hardware re-use is to deploy reconfigurable circuits. This is turn relies on embedded vector measurement to ensure the reconfigurable hardware operates as required. Conventional vector measurement techniques require costly and bulky Vector network analyzers or slightly more compact six-port junctions. Both options require the use directional couplers to sample forward and backward traveling waves, which increases their size and limits their suitability for embedding in reconfigurable RF hardware. Non-directional four-port interferometersoffer an alternative solution for embedded vector measurement that is characterized by a very small size, very low coupling, and ease of integration. In the present work, a new 3D 4-port non-directional reflectometer for measuring complex reflection coefficients is proposed. The proposed reflectometer features two optimized non-directional sniffers positioned below a transmission line with buried lines to carry the sniffed signals to power detectors in LTCC technology. Vertical transitions from the buried lines to surface are designed and optimized. 3D electromagnetic field simulations are used to optimize the proposed design in order to obtain the S-parameter of the structure. Two LT5582 power detector circuits with 57 dB dynamic range are used to detect the coupled power. A prototype of the proposed reflectometer is fabricated in LTCC (Ferro L8) in LACIME laboratory and used to measure 45 different complex loads. The obtained results show excellent agreement with VNA measurements showing errors below 0.3 dB for amplitude and below 3° for phase

    24 GHZ frequency modulation continuous wave radar front end system on substrate

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    Introduction -- Front-end system design -- Radar antenna design -- SIW/SIC mixers and surface-volume integration -- Integration of system-on-substrate and system experiments -- Conclusion and future work

    Development of a compact wireless SAW Pirani vacuum microsensor with extended range and sensitivity

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    Vakuumsensoren haben nach wie vor einen begrenzten Messbereich und erfordern eine aufwendige Verkabelung sowie eine komplexe Integration in Vakuumkammern. Ein kompakter Sensor, der in der Lage ist, den Erfassungsbereich zwischen Hochvakuum und Atmosphärendruck zu erweitern und dabei drahtlos zu arbeiten, ist äußerst wünschenswert. Der Schwerpunkt dieser Arbeit liegt auf dem Entwurf, der Simulation, der Herstellung und der experimentellen Validierung eines drahtlosen kompakten Vakuum-Mikrosensors mit erweiterter Reichweite und Empfindlichkeit. Zunächst wurde ein neuer Sensor unter Verwendung vorhandener und neu entwickelter Komponenten entworfen. Zweitens wurden die Sensorkomponenten simuliert, um ihre Parameter zu optimieren. Drittens wurde ein Prototyp unter Verwendung der verfügbaren Mikrobearbeitungs- und Halbleitertechnologien hergestellt und montiert. Viertens wurde der Prototyp unter Umgebungs- und Vakuumbedingungen charakterisiert, um seine Leistungen zu validieren. Für das Wandlerprinzip wurden zwei Techniken kombiniert, nämlich Pirani-Sensorik und akustische Oberflächenwellen. Das Design der Sensorkomponenten bestand aus vier Einheiten: Sensoreinheit, Heizeinheit, Abfrageeinheit und Gehäuse. Alle Einheiten wurden in einen kompakten Würfel eingebaut. Einige Komponenten wurden neu entwickelt, während andere gekauft, modifiziert und dann miteinander verbunden wurden. Die Sensoreinheit besteht aus einem neuen Chip mit verbesserter Sensorleistung dank eines optimierten Verhältnisses von Oberfläche zu Volumen. Die Heizeinheit wurde aus zwei induktiv gekoppelten Spulen und der zugehörigen Konditionierungselektronik zusammengesetzt. Die Abfrageeinheit wurde mit einer Mikro-Patch-Antenne hergestellt. Ein würfelförmiges Polymergehäuse wurde entwickelt, um alle Komponenten in einer Vakuumkammer unterzubringen. Zweitens wurde die Simulation des Verhaltens der Sensorkomponenten behandelt. Die für die Druckmessung verantwortliche Wärmeübertragung des Sensorchips wurde vom Hochvakuum bis zum Atmosphärendruck untersucht, um seine Abmessungen zu optimieren. Die Verwendung eines hängenden Lithium-Niobat-Chips mit Y-Z-Schnitt und einem TCF von 94 ppm/K führte zu einer verbesserten Leistung in einem Messbereich zwischen \num{d-4}~Pa und \num{e5}~Pa. Die elektronische Kopplung der Heizspulen wurde ebenfalls simuliert, um die Leistungsübertragung und den Kopplungsabstand zu optimieren. Der dritte Teil betrifft die Herstellungs- und Montageschritte des Prototyps unter Verwendung der verfügbaren Halbleitertechnologien und -ausrüstung. Ein SAW Chip wurde mit einer 100~nm dicken Goldschicht an der Unterseite gesputtert, um den Heizwiderstand zu bilden, und mit Hilfe von Drahtbonding elektrisch mit dem Rest des Sensors verbunden. Es wurde eine Leiterplatte vorbereitet, die die Heiz- und Sensoreinheit enthält. Ein kubisches Gehäusewurde aus PTFE hergestellt. Viertens wurden die Sensorkomponenten zunächst separat charakterisiert, um ihre Leistungen zu überprüfen, und dann zusammen unter Umgebungsbedingungen. Später wurde der Sensor im Vakuum integriert, und es wurde ein druckabhängiges Verhalten des Sensorchips beobachtet. Die Relevanz eines drahtlosen Übertragungsverfahrens wurde den herkömmlichen drahtgebundenen Methoden gegenübergestellt. Die Ergebnisse der experimentellen Arbeiten außerhalb und innerhalb des Vakuums zeigten die Machbarkeit und Relevanz des neuen Konzepts

    Characterisation of on-chip electrostatic discharge waveforms with sub-nanosecond resolution: design of a differential high voltage probe with high bandwidth

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    Bliksem werd tot aan de ontdekking van de bliksemafleider (18e eeuw) gezien als een van de gevaarlijkste bedreigingen voor het stadsleven. Door het gebruik van micro-elektronica werden ingenieurs gewaar dat ditzelfde fysische verschijnsel, elektrostatische ontlading of ESD genoemd, zich ook op microscopische schaal voordoet. In de jaren zeventig was meer dan 30% van al het chipfalen te wijten aan ESD. Om dit tegen te gaan werd met het onderzoek naar ESD-protecties en -meetsystemen aangevangen. Om meer informatie over het gedrag van een ESD-protectie te verkrijgen wordt een ESD-puls op dit systeem losgelaten. Het antwoord van de protectie op deze puls wordt dan bepaald m.b.v. spannings- en stroomgolfvormmetingen. In dit werk wordt een nieuwe nauwkeurige ESD-golfvormmeettechniek voorgesteld die directe metingen op protecties kan uitvoeren. De karakterisering van ESD-golfvormen op chip wordt enorm bemoeilijkt door de grote hoeveelheid elektromagnetische interferentie die de ESD-puls veroorzaakt. Dit wordt omzeild door het gewenste signaal naar een veilige omgeving te transporteren, waar een standaard meettoestel de meting kan uitvoeren. Dit transport wordt gerealiseerd m.b.v. optische communicatie, wat immuun is voor elektromagnetische interferentie. Zo kan nauwkeurige in-situ-informatie worden verkregen waarmee de ESD-protecties in de toekomst verbeterd kunnen worden.Up to the 18th century, lightning was considered one of nature’s most dangerous threats in city life. This all ended with the lightning rod, protecting thousands of homes during lightning storms. The large-scale use of microelectronics has made engineers aware of the same physical phenomenon occuring on a microscopic scale. This phenomenon is called electrostatic discharge or ESD. In the seventies, more than 30% of all chip failure was attributed to static electricity. To counter this effect, the research for on-chip ESD protections was born. Today ESD is a buzzing line of research, as with new and faster chip technologies comes a higher ESD vulnerability. This makes ESD protection and measurement increasingly important. Although ESD is now a major subject in chip design, it copes with a lack of accurate device models. To gain more information on the exact operation of an ESD protection, an ESD pulse is unleashed upon this device. The response of the protection on this pulse is then assessed by performing voltage or current waveform measurements. This work presents a waveform measurement technique able to accurately perform direct measurements on the ESD protection. Due to the high amount of electromagnetic interference caused by the ESD pulse, direct waveform characterisation near the protection is hard. This is solved by transporting the target signal into a clean area, where the measurement is performed by standard lab equipment. The key is that this transportation is realized by means of optical communication, which is immune to electromagnetic interference. This way, accurate in situ information can be used to protect tomorrow’s chips

    A superconducting tunnel junction receiver for millimeter-wave astronomy

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    The development and construction of an ultralow noise heterodyne receiver for millimeter wave astronomy is described along with its use for 115.3 GHz Co line observations. The receiver uses a Superconductor-Insulator-Superconductor (SIS) quasiparticle tunnel junction mixer to convert the millimeter wave signal to a microwave intermediate frequency. Experiments aimed at quantitative verification of J. R. Tucker's quantum mixer theory are studied, to see whether it could be used as the basis for the design of a practical receiver. The experimental results were in excellent agreement with the theory, assuming the three frequency approximation. Infinite available gain and negative output resistance were observed for the first time, nonclassical effects which are not seen in conventional diode mixers. Using Tucker's theory, an SIS receiver was then designed and constructed. At 115 GHz, the single sideband receiver noise temperature is 83K, the lowest ever reported in this frequency range. A CO survey toward Cygnus-X region, using this SIS receiver on the Columbia-GISS 4 ft. telescope, is also described

    Development of micromachined millimeter-wave modules for next-generation wireless transceiver front-ends

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    This thesis discusses the design, fabrication, integration and characterization of millimeter wave passive components using polymer-core-conductor surface micromachining technologies. Several antennas, including a W-band broadband micromachined monopole antenna on a lossy glass substrate, and a Ka-band elevated patch antenna, and a V-band micromachined horn antenna, are presented. All antennas have advantages such as a broad operation band and high efficiency. A low-loss broadband coupler and a high-Q cavity for millimeter-wave applications, using surface micromachining technologies is reported using the same technology. Several low-loss all-pole band-pass filters and transmission-zero filters are developed, respectively. Superior simulation and measurement results show that polymer-core-conductor surface micromachining is a powerful technology for the integration of high-performance cavity, coupler and filters. Integration of high performance millimeter-wave transceiver front-end is also presented for the first time. By elevating a cavity-filter-based duplexer and a horn antenna on top of the substrate and using air as the filler, the dielectric loss can be eliminated. A full-duplex transceiver front-end integrated with amplifiers are designed, fabricated, and comprehensively characterized to demonstrate advantages brought by this surface micromachining technology. It is a low loss and substrate-independent solution for millimeter-wave transceiver integration.Ph.D.Committee Chair: John Papapolymerou; Committee Chair: Manos Tentzeris; Committee Member: Gordon Stuber; Committee Member: John Cressler; Committee Member: John Z. Zhang; Committee Member: Joy Laska

    Sistema de medida analógico-digital para software-defined radios

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    Mestrado em Engenharia Eléctrónica e TelecomunicaçõesEsta disserta c~ao insere-se na area de metrologia de r adio-frequ^encia, procurando colmatar a actual lacuna de instrumentos capazes de caracterizar r apida e e cazmente um componente anal ogico-digital, tal como uma ADC ou DAC. Estes componentes s~ao elementos chave da concep c~ao de arquitecturas Software-De ned Radio (SDR). O conceito de SDR de ne um r adio que seja totalmente adapt avel por software, atrav es da transi c~ao de blocos do dom nio anal ogico para o dom nio digital. Assim sendo, a adop c~ao destas arquitecturas r adio ir a ser cada vez mais utilizada de forma a responder a crescente necessidade de receber diversos tipos de comunica c~ao num unico terminal. Neste trabalho prop~oem-se a implementa c~ao de um instrumento que caracterize componentes anal ogico-digitais da mesma forma que o tradicional e popular Vector Network Analyzer (VNA) faz para componentes anal ogicos. Procura-se fornecer a um projectista de r adio, uma ferramenta que permita prever o desempenho de um componente anal ogico-digital do ponto de vista de r adio, de forma a facilitar o projecto de novos e mais complexos sistemas SDR. A implementa c~ao proposta pretende caracterizar componentes na banda de frequ^encias dos 40 aos 1000 MHz. Diversos ensaios foram realizados de forma a mostrar a comunidade cient ca a mais-valia deste instrumento.This thesis is inserted into the Radio-Frequency metrology, it pursuits to ful l the current gap of instrumentation able to characterize analog-digital components, as ADC or DAC's, in a quickly and e ective form. These analog-digital components are the key to the conception of Software-De ned Radio (SDR) architectures. The SDR concept de nes a radio system totally implemented by means of software, where the of most the components operate in digital domain. Therefore, these architectures are becoming more and more used due to the growing need of receiving di erent kinds of communications in only one terminal. This paper tries to set up an instrument capable of characterize mixeddomain components as the tradicional and popular VNA can do with analog components. It is tried to built a new brand tool that can give to the radio designer, an easy form to create other SDR complex projects. The proposed instrument pretends to characterize components from 40 to 1000MHz bandwidth. Several tests were made in order to show its added value to the scienti c community
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