The Expanded Very Large Array

In almost 30 years of operation, the Very Large Array (VLA) has proved to be a remarkably flexible and productive radio telescope. However, the basic capabilities of the VLA have changed little since it was designed. A major expansion utilizing modern technology is currently underway to improve the capabilities of the VLA by at least an order of magnitude in both sensitivity and in frequency coverage. The primary elements of the Expanded Very Large Array (EVLA) project include new or upgraded receivers for continuous frequency coverage from 1 to 50 GHz, new local oscillator, intermediate frequency, and wide bandwidth data transmission systems to carry signals with 16 GHz total bandwidth from each antenna, and a new digital correlator with the capability to process this bandwidth with an unprecedented number of frequency channels for an imaging array. Also included are a new monitor and control system and new software that will provide telescope ease of use. Scheduled for completion in 2012, the EVLA will provide the world research community with a flexible, powerful, general-purpose telescope to address current and future astronomical issues.Comment: Added journal reference: published in Proceedings of the IEEE, Special Issue on Advances in Radio Astronomy, August 2009, vol. 97, No. 8, 1448-1462 Six figures, one tabl

Photonic Vector Processing Techniques for Radiofrequency Signals

[EN] The processing of radiofrequency signals using photonics means is a discipline that appeared almost at the same time as the laser and the optical fibre. Photonics offers the capability of managing broadband radiofrequency (RF) signals thanks to its low transmission attenuation, a variety of linear and non-linear phenomena and, recently, the potential to implement integrated photonic subsystems. These features open the door for the implementation of multiple functionalities including optical transportation, up and down frequency conversion, optical RF filtering, signal multiplexing, de-multiplexing, routing and switching, optical sampling, tone generation, delay control, beamforming and photonic generation of digital modulations, and even a combination of several of these functionalities. This thesis is focused on the application of vector processing in the optical domain to radiofrequency signals in two fields of application: optical beamforming, and photonic vector modulation and demodulation of digital quadrature amplitude modulations. The photonic vector control enables to adjust the amplitude and phase of the radiofrequency signals in the optical domain, which is the fundamental processing that is required in different applications such as beamforming networks for direct radiating array (DRA) antennas and multilevel quadrature modulation. The work described in this thesis include different techniques for implementing a photonic version of beamforming networks for direct radiating arrays (DRA) known as optical beamforming networks (OBFN), with the objectives of providing a precise control in terrestrial applications of broadband signals at very high frequencies above 40 GHz in communication antennas, optimizing the size and mass when compared with the electrical counterparts in space application, and presenting new photonic-based OBFN functionalities. Thus, two families of OBFNs are studied: fibre-based true time delay architectures and integrated networks. The first allow the control of broadband signals using dispersive optical fibres with wavelength division multiplexing techniques and advanced functionalities such as direction of arrival estimation in receiving architectures. In the second, passive OBFNs based on monolithically-integrated Optical Butler Matrices are studied, including an ultra-compact solution using optical heterodyne techniques in silicon-on-insulator (SOI) material, and an alternative implementing a homodyne counterpart in germanium doped silica material. In this thesis, the application of photonic vector processing to the generation of quadrature digital modulations has also been investigated. Multilevel modulations are based on encoding digital information in discrete states of phase and amplitude of an electrical signal to enhance spectral efficiency, as for instance, in quadrature modulation. The signal process required for generating and demodulating this kind of signals involves vector processing (phase and amplitude control) and frequency conversion. Unlike the common electronic or digital implementation, in this thesis, different photonic based signal processing techniques are studied to produce digital modulation (photonic vector modulation, PVM) and demodulation (PVdM). These techniques are of particular interest in the case of broadband signals where the data rate required to be managed is in the order of gigabit per second, for applications like wireless backhauling of metro optical networks (known as fibre-to-the-air). The techniques described use optical dispersion in optical fibres, wavelength division multiplexing and photonic up/down conversion. Additionally, an optical heterodyne solution implemented monolithically in a photonic integrated circuit (PIC) is also described.[ES] El procesamiento de señales de radiofrecuencia (RF) utilizando medios fotónicos es una disciplina que apareció casi al mismo tiempo que el láser y la fibra óptica. La fotónica ofrece la capacidad de manipular señales de radiofrecuencia de banda ancha, una baja atenuación, procesados basados en una amplia variedad de fenómenos lineales y no lineales y, recientemente, el potencial para implementar subsistemas fotónicos integrados. Estas características ofrecen un gran potencial para la implementación de múltiples funcionalidades incluyendo transporte óptico, conversión de frecuencia, filtrado óptico de RF, multiplexación y demultiplexación de señales, encaminamiento y conmutación, muestreo óptico, generación de tonos, líneas de retardo, conformación de haz en agrupaciones de antenas o generación fotónica de modulaciones digitales, e incluso una combinación de varias de estas funcionalidades. Esta tesis se centra en la aplicación del procesamiento vectorial en el dominio óptico de señales de radiofrecuencia en dos campos de aplicación: la conformación óptica de haces y la modulación y demodulación vectorial fotónica de señales digitales en cuadratura. El control fotónico vectorial permite manipular la amplitud y fase de las señales de radiofrecuencia en el dominio óptico, que es el procesamiento fundamental que se requiere en diferentes aplicaciones tales como las redes de conformación de haces para agrupaciones de antenas y en la modulación en cuadratura. El trabajo descrito en esta tesis incluye diferentes técnicas para implementar una versión fotónica de las redes de conformación de haces de en agrupaciones de antenas, conocidas como redes ópticas de conformación de haces (OBFN). Se estudian dos familias de redes: arquitecturas de retardo en fibra óptica y arquitecturas integradas. Las primeras permiten el control de señales de banda ancha utilizando fibras ópticas dispersivas con técnicas de multiplexado por división de longitud de onda y funcionalidades avanzadas tales como la estimación del ángulo de llegada de la señal en la antena receptora. En la segunda, se estudian redes de conformación pasivas basadas en Matrices de Butler ópticas integradas, incluyendo una solución ultra-compacta utilizando técnicas ópticas heterodinas en silicio sobre aislante (SOI), y una alternativa homodina en sílice dopado con germanio. En esta tesis, también se han investigado técnicas de procesado vectorial fotónico para la generación de modulaciones digitales en cuadratura. Las modulaciones multinivel codifican la información digital en estados discretos de fase y amplitud de una señal eléctrica para aumentar su eficiencia espectral, como por ejemplo la modulación en cuadratura. El procesado necesario para generar y demodular este tipo de señales implica el procesamiento vectorial (control de amplitud y fase) y la conversión de frecuencia. A diferencia de la implementación electrónica o digital convencional, en esta tesis se estudian diferentes técnicas de procesado fotónico tanto para la generación de modulaciones digitales (modulación vectorial fotónica, PVM) como para su demodulación (PVdM). Esto es de particular interés en el caso de señales de banda ancha, donde la velocidad de datos requerida es del orden de gigabits por segundo, para aplicaciones como backhaul inalámbrico de redes ópticas metropolitanas (conocida como fibra hasta el aire). Las técnicas descritas se basan en explotar la dispersión cromática de la fibra óptica, la multiplexación por división de longitud de onda y la conversión en frecuencia. Además, se presenta una solución heterodina implementada monolíticamente en un circuito integrado fotónico (PIC).[CA] El processament de senyals de radiofreqüència (RF) utilitzant mitjans fotònics és una disciplina que va aparèixer gairebé al mateix temps que el làser i la fibra òptica. La fotònica ofereix la capacitat de manipular senyals de radiofreqüència de banda ampla, una baixa atenuació, processats basats en una àmplia varietat de fenòmens lineals i no lineals i, recentment, el potencial per implementar subsistemes fotònics integrats. Aquestes característiques ofereixen un gran potencial per a la implementació de múltiples funcionalitats incloent transport òptic, conversió de freqüència, filtrat òptic de RF, multiplexació i demultiplexació de senyals, encaminament i commutació, mostreig òptic, generació de tons, línies de retard, conformació de feix en agrupacions d'antenes i la generació fotònica de modulacions digitals, i fins i tot una combinació de diverses d'aquestes funcionalitats. Aquesta tesi es centra en l'aplicació del processament vectorial en el domini òptic de senyals de radiofreqüència en dos camps d'aplicació: la conformació òptica de feixos i la modulació i demodulació vectorial fotònica de senyals digitals en quadratura. El control fotònic vectorial permet manipular l'amplitud i la fase dels senyals de radiofreqüència en el domini òptic, que és el processament fonamental que es requereix en diferents aplicacions com ara les xarxes de conformació de feixos per agrupacions d'antenes i en modulació multinivell. El treball descrit en aquesta tesi inclou diferents tècniques per implementar una versió fotònica de les xarxes de conformació de feixos en agrupacions d'antenes, conegudes com a xarxes òptiques de conformació de feixos (OBFN), amb els objectius de proporcionar un control precís en aplicacions terrestres de senyals de banda ampla a freqüències molt altes per sobre de 40 GHz en antenes de comunicacions, optimitzant la mida i el pes quan es compara amb els homòlegs elèctrics en aplicacions espacials, i la presentació de noves funcionalitats fotòniques per agrupacions d'antenes. Per tant, s'estudien dues famílies de OBFNs: arquitectures de retard en fibra òptica i arquitectures integrades. Les primeres permeten el control de senyals de banda ampla utilitzant fibres òptiques dispersives amb tècniques de multiplexació per divisió en longitud d'ona i funcionalitats avançades com ara l'estimació de l'angle d'arribada del senyal a l'antena receptora. A la segona, s'estudien xarxes de conformació passives basades en Matrius de Butler òptiques en fotònica integrada, incloent una solució ultra-compacta utilitzant tècniques òptiques heterodinas en silici sobre aïllant (SOI), i una alternativa homodina en sílice dopat amb germani. D'altra banda, també s'ha investigat en aquesta tesi tècniques de processament vectorial fotònic per a la generació de modulacions digitals en quadratura. Les modulacions multinivell codifiquen la informació digital en estats discrets de fase i amplitud d'un senyal elèctric per augmentar la seva eficiència espectral, com ara la modulació en quadratura. El processat necessari per generar i desmodular aquest tipus de senyals implica el processament vectorial (control d'amplitud i fase) i la conversió de freqüència. A diferència de la implementació electrònica o digital convencional, en aquesta tesi s'estudien diferents tècniques de processament fotònic tant per a la generació de modulacions digitals (modulació vectorial fotònica, PVM) com per la seva demodulació (PVdM). Això és de particular interès en el cas de senyals de banda ampla, on la velocitat de dades requerida és de l'ordre de gigabits per segon, per a aplicacions com backhaul sense fils de xarxes òptiques metropolitanes (coneguda com fibra fins l'aire). Les tècniques descrites es basen en explotar la dispersió cromàtica de la fibra òptica, la multiplexació per divisió en longitud d'ona i la conversió en freqüència. A més, es presePiqueras Ruipérez, MÁ. (2016). Photonic Vector Processing Techniques for Radiofrequency Signals [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/63264TESI

Analysis and Design of a Sub-THz Ultra-Wideband Phased-Array Transmitter

This thesis investigates circuits and systems for broadband high datarate transmitter systems in the millimeter-wave (mm-wave) spectrum. During the course of this dissertation, the design process and characterization of a power efficient and wideband binary phase-shift keying (BPSK) transmitter integrated circuit (IC) with local oscillator (LO) frequency multiplication and 360° phase control for beam steering is studied. All required circuit blocks are designed based on the theoretical analysis of the underlying principles, optimized, fabricated and characterized in the research laboratory targeting low power consumption, high efficiency and broadband operation. The phase-controlled push-push (PCPP) architecture enabling frequency multiplication by four in a single stage is analytically studied and characterized finding an optimum between output power and second harmonic suppression depending on the input amplitude. A PCPP based LO chain is designed. A circuit is fabricated establishing the feasibility of this architecture for operation at more than 200 GHz. Building on this, a second circuit is designed, which produces among the highest saturated output powers at 2 dBm. At less than 100 mW of direct current (DC) power consumption, this results in a power-added efficiency (PAE) of 1.6 % improving the state of the art by almost 30 %. Phase-delayed and time-delayed approaches to beam steering are analyzed, identifying and discussing design challenges like area consumption, signal attenuation and beam squint. A 60 GHz active vector-sum phase-shifter with high gain of 11.3 dB and output power of 5 dBm, improving the PAE of the state of the art by a factor of 30 achieving 6.29 %, is designed. The high gain is possible due to an optimization of the orthogonal signal creation stage enabled by studying and comparing different architectures leading to a trade off of lower signal attenuation for higher area consumption in the chosen electromagnetic coupler. By combining this with a frequency quadrupler, a phase steering enabled LO chain for operation at 220 GHz is created and characterized, confirming the preceding analysis of the phase-frequency relation during multiplication. It achieves a power gain of 21 dB, outperforming comparable designs by 25 dB. This allows the combination of phase control, frequency multiplication and pre-amplification. The radio frequency (RF) efficiency is increased 40-fold to 0.99 %, with a total power consumption of 105 mW. Motivated by the distorting effect of beam squint in phase-delayed broadband array systems, a novel analog hybrid beam steering architecture is devised, combining phase-delayed and time-delayed steering with the goal of reducing the beam squint of phase-delayed systems and large area consumption of time-delayed circuits. An analytical design procedure is presented leading to the research finding of a beam squint reduction potential of more than 83 % in an ideal system. Here, the increase in area consumption is outweighed by the reduction in beam squint. An IC with a low power consumption of 4.3 mW has been fabricated and characterized featuring the first time delay circuit operating at above 200 GHz. By producing most of the beam direction by means of time delay the beam squinting can be reduced by more than 75 % in measurements while the subsequent phase shifter ensures continuous beam direction control. Together, the required silicon area can be reduced to 43 % compared to timedelayed systems in the same frequency range. Based on studies of the optimum signal feeding and input matching of a Gilbert cell, an ultra-wideband, low-power mixer was designed. A bandwidth of more than 100 GHz was achieved exceeding the state of the art by 23 %. With a conversion gain of –13 dB, this enables datarates of more than 100 Gbps in BPSK operation. The findings are consolidated in an integrated transmitter operating around 246 GHz doubling the highest published measured datarates of transmitters with LO chain and power amplifier in BPSK operation to 56 Gbps. The resulting transmitter efficiency of 7.4 pJ/bit improves the state of the art by 70 % and 50 % over BPSK and quadrature phaseshift keying (QPSK) systems, respectively. Together, the results of this work form the basis for low-power and efficient next-generation wireless applications operating at many times the datarates available today.:Abstract 3 Zusammenfassung 5 List of Symbols 11 List of Acronyms 17 Prior Publications 19 1. Introduction 21 1.1. Motivation........................... 21 1.2. Objective of this Thesis ................... 25 1.3. Structure of this Thesis ................... 27 2. Overview of Employed Technologies and Techniques 29 2.1. IntegratedCircuitTechnology................ 29 2.2. Transmission Lines and Passive Structures . . . . . . . . 35 2.3. DigitalModulation ...................... 41 3. Frequency Quadrupler 45 3.1. Theoretical Analysis of Frequency Multiplication Circuits 45 3.2. Phase-Controlled Push-Push Principle for Frequency Quadrupling.......................... 49 3.3. Stand-alone Phase-Controlled Push-Push Quadrupler . 60 3.4. Phase-Controlled Push-Push Quadrupler based LO-chain with High Output Power ............... 72 9 4. Array Systems and Dynamic Beam Steering 91 4.1. Theoretical Analysis of BeamSteering. . . . . . . . . . . 95 4.2. Local Oscillator Phase Shifting with Vector-Modulator PhaseShifters......................... 107 4.3. Hybrid True-Time and Phase-Delayed Beam Steering . 131 5. Ultra-Wide Band Modulator for BPSK Operation 155 6. Broadband BPSK Transmitter System for Datarates up to 56 Gbps 167 6.1. System Architecture ..................... 168 6.2. Measurement Technique and Results . . . . . . . . . . . 171 6.3. Summary and performance comparison . . . . . . . . . 185 7. Conclusion and Outlook 189 A. Appendix 195 Bibliography 199 List of Figures 227 Note of Thanks 239 Curriculum Vitae 241Diese Dissertation untersucht Schaltungen und Systeme für breitbandige Transmittersysteme mit hoher Datenrate im Millimeterwellen (mm-wave) Spektrum. Im Rahmen dieser Arbeit werden der Entwurfsprozess und die Charakterisierung eines leistungseffizienten und breitbandigen integrierten Senders basierend auf binärer Phasenumtastung (BPSK) mit Frequenzvervielfachung des Lokaloszillatorsignals und 360°-Phasenkontrolle zur Strahlsteuerung untersucht. Alle erforderlichen Schaltungsblöcke werden auf Grundlage von theoretischen Analysen der zugrundeliegenden Prinzipien entworfen, optimiert, hergestellt und im Forschungslabor charakterisiert, mit den Zielen einer niedrigen Leistungsaufnahme, eines hohen Wirkungsgrades und einer möglichst großen Bandbreite. Die phasengesteuerte Push-Push (PCPP)-Architektur, welche eine Frequenzvervierfachung in einer einzigen Stufe ermöglicht, wird analytisch untersucht und charakterisiert. Dabei wird ein Optimum zwischen Ausgangsleistung und Unterdrückung der zweiten Harmonischen des Eingangssignals in Abhängigkeit von der Eingangsamplitude gefunden. Es wird eine LO-Kette auf PCPP-Basis entworfen. Eine Schaltung wird präsentiert, die die Machbarkeit dieser Architektur für den Betrieb bei mehr als 200 GHz nachweist. Darauf aufbauend wird eine zweite Schaltung entworfen, die mit 2 dBm eine der höchsten publizierten gesättigten Ausgangsleistungen erzeugt. Mit einer Leistungsaufnahme von weniger als 100mW ergibt sich ein Leistungswirkungsgrad (PAE) von 1.6 %, was den Stand der Technik um fast 30 % verbessert. Es werden phasenverzögerte und zeitverzögerte Ansätze zur Steuerung der Strahlrichtung analysiert, wobei Entwicklungsherausforderungen wie Flächenverbrauch, Signaldämpfung und Strahlschielen identifiziert und diskutiert werden. Ein aktiver Vektorsummen-Phasenschieber mit hoher Verstärkung von 11.3 dB und einer Ausgangsleistung von 5 dBm, der mit einer PAE von 6.29 % den Stand der Technik um den Faktor 30 verbessert, wird entworfen. Die hohe Verstärkung ist zum Teil auf eine Optimierung der orthogonalen Signalerzeugungsstufe zurückzuführen, die durch die Untersuchung und den Vergleich verschiedener Architekturen ermöglicht wird. Bei der Entscheidung für einen elektromagnetischen Koppler rechtfertigt die geringere Signaldämpfung einen höheren Flächenverbrauch. Durch die Kombination mit einem Frequenzvervierfacher wird eine LO-Kette mit Phasensteuerung für den Betrieb bei 220 GHz geschaffen und charakterisiert, was die vorangegangene Analyse der Phasen-FrequenzBeziehung während der Multiplikation bestätigt. Sie erreicht einen Leistungsgewinn von 21 dB und übertrifft damit vergleichbare Designs um 25dB. Dies ermöglicht die Kombination von Phasensteuerung, Frequenzvervielfachung und Vorverstärkung. Der HochfrequenzWirkungsgrad wird um das 40-fache auf 0.99 % bei einer Gesamtleistungsaufnahme von 105 mW gesteigert. Motiviert durch den verzerrenden Effekt des Strahlenschielens in phasengesteuerten Breitbandarraysystemen, wird eine neuartige analoge hybride Strahlsteuerungsarchitektur untersucht, die phasenverzögerte und zeitverzögerte Steuerung kombiniert. Damit wird sowohl das Strahlenschielen phasenverzögerter Systeme als auch der große Flächenverbrauch zeitverzögerter Schaltungen reduziert. Es wird ein analytisches Entwurfsverfahren vorgestellt, das zu dem Forschungsergebnis führt, dass in einem idealen System ein Potenzial zur Reduktion des Strahlenschielens von mehr als 83 % besteht. Dabei wird die Zunahme des Flächenverbrauchs durch die Verringerung des Strahlenschielens aufgewogen. Es wird ein IC mit einer geringen Leistungsaufnahme von 4.3mW hergestellt und charakterisiert. Dabei wird die erste Zeitverzögerungsschaltung entworfen, die bei über 200 GHz arbeitet. Durch die Erzeugung eines Großteils der Strahlrichtung mittels Zeitverzögerung kann das Schielen des Strahls bei Messungen um mehr als 75% reduziert werden, während der nachfolgende Phasenschieber eine kontinuierliche Steuerung der Strahlrichtung gewährleistet. Insgesamt kann die benötigte Siliziumfläche im Vergleich zu zeitverzögerten Systemen im gleichen Frequenzbereich auf 43 % reduziert werden. Auf der Grundlage von Studien zur optimalen Signaleinspeisung und Eingangsanpassung einer Gilbert-Zelle wird ein Ultrabreitband-Mischer mit geringem Stromverbrauch entworfen. Dieser erreicht eine Ausgangsbandbreite von mehr als 100 GHz, die den Stand der Technik um 23% übertrifft. Bei einer Wandlungsverstärkung von –13dB ermöglicht dies Datenraten von mehr als 100 Gbps im BPSK-Betrieb. Die Erkenntnisse werden in einem integrierten, breitbandigen Sender konsolidiert, der um 246 GHz arbeitet und die höchsten veröffentlichten gemessenen Datenraten für Sender mit LO-Signalkette und Leistungsverstärker im BPSK-Betrieb auf 56 Gbps verdoppelt. Die daraus resultierende Transmitter-Effizienz von 7.4 pJ/bit verbessert den Stand der Technik um 70 % bzw. 50 % gegenüber BPSKund Quadratur Phasenumtastung (QPSK)-Systemen. Zusammen bilden die Ergebnisse dieser Arbeit die Grundlage für stromsparende, effiziente, mobile Funkanwendungen der nächsten Generation mit einem Vielfachen der heute verfügbaren Datenraten.:Abstract 3 Zusammenfassung 5 List of Symbols 11 List of Acronyms 17 Prior Publications 19 1. Introduction 21 1.1. Motivation........................... 21 1.2. Objective of this Thesis ................... 25 1.3. Structure of this Thesis ................... 27 2. Overview of Employed Technologies and Techniques 29 2.1. IntegratedCircuitTechnology................ 29 2.2. Transmission Lines and Passive Structures . . . . . . . . 35 2.3. DigitalModulation ...................... 41 3. Frequency Quadrupler 45 3.1. Theoretical Analysis of Frequency Multiplication Circuits 45 3.2. Phase-Controlled Push-Push Principle for Frequency Quadrupling.......................... 49 3.3. Stand-alone Phase-Controlled Push-Push Quadrupler . 60 3.4. Phase-Controlled Push-Push Quadrupler based LO-chain with High Output Power ............... 72 9 4. Array Systems and Dynamic Beam Steering 91 4.1. Theoretical Analysis of BeamSteering. . . . . . . . . . . 95 4.2. Local Oscillator Phase Shifting with Vector-Modulator PhaseShifters......................... 107 4.3. Hybrid True-Time and Phase-Delayed Beam Steering . 131 5. Ultra-Wide Band Modulator for BPSK Operation 155 6. Broadband BPSK Transmitter System for Datarates up to 56 Gbps 167 6.1. System Architecture ..................... 168 6.2. Measurement Technique and Results . . . . . . . . . . . 171 6.3. Summary and performance comparison . . . . . . . . . 185 7. Conclusion and Outlook 189 A. Appendix 195 Bibliography 199 List of Figures 227 Note of Thanks 239 Curriculum Vitae 24

Four-element phased-array beamformers and a self-interference canceling full-duplex transciver in 130-nm SiGe for 5G applications at 26 GHz

This thesis is on the design of radio-frequency (RF) integrated front-end circuits for next generation 5G communication systems. The demand for higher data rates and lower latency in 5G networks can only be met using several new technologies including, but not limited to, mm-waves, massive-MIMO, and full-duplex. Use of mm-waves provides more bandwidth that is necessary for high data rates at the cost of increased attenuation in air. Massive-MIMO arrays are required to compensate for this increased path loss by providing beam steering and array gain. Furthermore, full duplex operation is desirable for improved spectrum efficiency and reduced latency. The difficulty of full duplex operation is the self-interference (SI) between transmit (TX) and receive (RX) paths. Conventional methods to suppress this interference utilize either bulky circulators, isolators, couplers or two separate antennas. These methods are not suitable for fully-integrated full-duplex massive-MIMO arrays. This thesis presents circuit and system level solutions to the issues summarized above, in the form of SiGe integrated circuits for 5G applications at 26 GHz. First, a full-duplex RF front-end architecture is proposed that is scalable to massive-MIMO arrays. It is based on blind, RF self-interference cancellation that is applicable to single/shared antenna front-ends. A high resolution RF vector modulator is developed, which is the key building block that empowers the full-duplex frontend architecture by achieving better than state-of-the-art 10-b monotonic phase control. This vector modulator is combined with linear-in-dB variable gain amplifiers and attenuators to realize a precision self-interference cancellation circuitry. Further, adaptive control of this SI canceler is made possible by including an on-chip low-power IQ downconverter. It correlates copies of transmitted and received signals and provides baseband/dc outputs that can be used to adaptively control the SI canceler. The solution comes at the cost of minimal additional circuitry, yet significantly eases linearity requirements of critical receiver blocks at RF/IF such as mixers and ADCs. Second, to complement the proposed full-duplex front-end architecture and to provide a more complete solution, high-performance beamformer ICs with 5-/6- b phase and 3-/4-b amplitude control capabilities are designed. Single-channel, separate transmitter and receiver beamformers are implemented targeting massive- MIMO mode of operation, and their four-channel versions are developed for phasedarray communication systems. Better than state-of-the-art noise performance is obtained in the RX beamformer channel, with a full-channel noise figure of 3.3 d

High-gain self-steering microwave repeater, volume 1 Final engineering report, Jan. 1966 - Apr. 1969

Engineering model of high gain self steering microwave transponder and application to satellite communication link

Circuit Techniques for Multiple and Wideband Beamforming

University of Minnesota Ph.D. dissertation.June 2018. Major: Electrical Engineering. Advisor: Ramesh Harjani. 1 computer file (PDF); x, 102 pages.This thesis presents different architectures with regard to multiple beamforming and wideband phased array transceiver. Three different designs are implemented in TSMC 65nm RF CMOS to demonstrate different solutions. The design in this thesis have included major RF blocks in state-of-art wireless transceiver: RF receiver, local oscillator, and RF transmitter. First, a RF/analog FFT based four-channel four-beam receiver with progressive partial spatial ltering is proposed. This architecture is particularly well suited for MIMO systems where multiple beams are used to increase throughput. Like the FFT, the proposed architecture reuses computations for multi-beam systems. In particular, the proposed architecture redistributes the computations so as to maximize the reuse of the structure that already exist in a receiver chain. In many fashions the architecture is quite similar to a Butler matrix but unlike the Butler matrix it does not use large passive components at RF. Further, we exploit the normally occurring quadrature down-conversion process to implement the tap weights. In comparison to traditional MIMO architectures, that effectively duplicate each path, the distributed computations of this architecture provide partial spatial ltering before the final stage, improving interference rejection for the blocks between the LNA and the ADC. Additionally, because of the spatial ltering prior to the ADC, a single interferer only jams a single beam allowing for continued operation though at a lower combined throughput. The four-beam receiver core prototype in 65nm CMOS implements the basic FFT based architecture but does not include an LNA or extensive IF stages. This four-channel design consumes 56mW power and occupies an active area of 0:65mm2 excluding pads and test circuits. Second, a wideband phased array receiver architecture with simultaneous spectral and spatial filtering by sub-harmonic injection oscillators is presented. The design avoids using expensive delay elements by many conventional wideband phased array. Different from prior art of channelization which cannot solve beam-squinting issue among the sub-channels, we use sub-harmonic injection locking scheme, which make the center frequencies of all sub-channels point to the same spatial direction to overcome beam-squinting issue. The low frequency, low power and narrowband phase shifters are placed at LO in comparison to conventional way of placing delay elements or phase shifters in the signal path. This avoids receiver performance degradation from delay elements or phase shifters. The simultaneous spectral and spatial ltering dictates less ADC dynamic range requirement and further reduces power. The injection locking scheme reduces the phase noise contribution from the oscillators. The two-band prototype design realized in 65nm GP CMOS is centered at 9GHz, provides 4GHz instantaneous bandwidth, reduces beam-squinting by half, consumes 31.75mW/antenna and occupies 2.7mm2 of chip area. In the third work, a steerable RF/analog FFT based four-beam transmitter architecture is presented. This work is based on the idea of FFT based multiple beamforming in 1st work, but extended to the transmitter and make the all beams steerable. Due to the reciprocity between receiver and transmitter, decimation-in-frequency (DIF) FFT is utilized in the transmitter. All the beams are steered simultaneously by front-end phase shifters, while keep each of the beams is independent of the others. The steerability of FFT based multiple beamforming scheme makes this proposed prototype could tackle more complicated portable wireless environment. The first and second proposed architecture have been silicon veried, and the design of the third has been finished and ready for tapeout