Lignes couplées à ondes lentes intégrées sur silicium en bande millimétrique - Application aux coupleurs, filtres et baluns

This work focuses on high-performances CS-CPW (Coupled Slow-wave CoPlanar Waveguide) transmission lines in classical CMOS integrated technologies for the millimiter-wave frequency band. First, the theory as well as the electrical models of the CS-CPW are presented. Thanks to the models and electromagnetic simulations, directional couplers with different coupling levels (3 dB, 10 dB, 18 dB) were designed in BiCMOS 55 nm technology. They have a good directivity, always better than 15 dB. A first prototype of a coupler was measured at 150 GHz presenting good agreement with the simulations. Next, coupled-line base filters were developed at 80 GHz using the CS-CPWs. Simulation present competitive results with the state-of-art: 11% of fractional bandwidth and a unload quality factor of 25. Finally, three projects started based on the CS-CPWs. The projects are currently used in two theses and one internship: a RTPS at 47 GHz, an isolator at 75 GHz and a balun at 80 GHz.L’objectif de ce travail de thèse est le développement en technologie intégrée standard d’une structure de ligne de transmission optimisée en termes de pertes, d’encombrement, de facteur de qualité et surtout du choix du niveau de couplage aux fréquences millimétriques. Cette structure a été nommée CS-CPW (Coupled Slow-wave CoPlanar Waveguide). Dans un premier temps, la théorie ainsi que les modèles électriques des CS-CPW sont présentés. Grâce aux modèles et aux simulations électromagnétiques, des coupleurs directionnels avec plusieurs valeurs de couplage (3 dB, 10 dB, 18 dB) ont été conçus en technologie BiCMOS 55 nm. Ils présentent tous une très bonne directivité, elle est toujours supérieure à 15 dB. Un premier prototype de coupleur a été mesuré à 150 GHz. Dans un deuxième temps, des filtres à la base des lignes couplées ont été développés à 80 GHz en utilisant des lignes CS-CPW. Les résultats des simulations présentent des résultats concurrentiels avec l’état de l’art : 11% de bande passante relative et un facteur non-chargé autour de 25. Finalement, trois projets ont démarré à la base de ces lignes. Ces projets sont actuellement utilisés dans deux travaux de thèse et un stage : un RTPS à 47 GHz, un isolateur à 75 GHz et un balun à 80 GHz

Broad-band microwave amplifier design considerations

Broad-band microwave integrated circuit (MIC) amplifier design is a complex, multi-disciplinary process. This work focuses on three important aspects: the behaviour of microstrip transmission lines, discontinuities, and related structures; the accurate measurement of components and devices mounted in microstrip circuits; and the circuit design methodology. Techniques for microstrip quasi-static analysis are reviewed in order to identify methods suitable for extension to deal with the effects of substrate anisotropy. An integral equation method is described and the anisotropic Green's function derived using an extension to the method of partial images. Proposed transform methods are assessed and the preferred option implemented by adaption of a microstrip analysis computer program. A method, by which accurate measurements of microstrip properties may be made, is developed. Involving measurements of the resonant behaviour of half-wavelength short circuit resonators with two arbitrary coupling conditions, this technique allows the unloaded properties to be deduced. Results for microstrip on a sapphire substrate concur with the analysis. A pragmatic but effective approach to the calculation of the capacity component of microstrip discontinuities, and some other three dimensional MIC structures, is described and developed to allow existing data for isotropic substrates to be applied to the anisotropic situation. The computer corrected network analyser (CCNA) is a widely used microwave measurement tool. Weaknesses in popular correction strategies are identified and remedies developed. In particular, revised calibration equations that better accommodate test port mismatch variation with s-parameter selection, and a model for quadrature error are presented. A 2-port calibration scheme suitable for use with MIC transmission lines, using only simple standards, is described. The standards are partially self-calibrating;the values of propagation constant, loss, and end effect are deduced in the calibration process. An effective jig for use with microstrip is described and the results of measurements on microwave transistors presented. Conventionally microwave amplifiers are designed using reactive components both to achieve good port matches and compensate the frequency dependent gain of the active devices. The problems associated with this approach are enumerated and the alternatives reviewed. A methodology which combines the benefits of frequency dependant dissipative networks with the elegance of reactive network synthesis is described. The device gain slope is compensated by simple lumped or distributed circuits incorporating a resistive element to produce a composite `device' with a specififed (flat) maximum available gain frequency response. Reactive matching networks are then used to interface these gain blocks. By this structured approach the amplifier gain breakdown can be defined at the outset and preserved through the design process. Other advantages stemming from the use of dissipative compensation include improved tolerance to device parameter and component value scatter, reduced group delay variations and enhanced reverse isolation. The method is demonstrated by the design and characterisation of 4 to 9 GHz amplifier having a representative specification. The close conformance of the performance of the untrimmed amplifier to that predicted by computer simulation testifies to the inherent accuracy of the design method, the microstrip (and related structures) analysis techniques and the CCNA MIC calibration scheme

Development of Compact UWB Transmit Receive Modules and Filters on Liquid Crystal Polymer for Radar

This thesis presents the design and development of various microwave components for an airborne snow-probing radar with multi-gigahertz bandwidth and cm-scale vertical resolution. First, a set of ultra-wideband, modular transmit and receive modules with custom power sequencing circuits is presented. These modules were rapid-prototyped as an initial step toward the miniaturization of the radar’s front-end, using a combination of custom and COTS circuits. The transmitter and receiver modules operate in the 2–18 GHz range. Laboratory and field tests are discussed, demonstrating performance that is comparable to previous, connectorized implementations, while accomplishing a 5:1 size reduction. Next, a set of miniaturized band-pass and low-pass filters is developed and demonstrated. This work addressed the lack of COTS circuits with adequate performance in a sufficiently small form factor that is compatible with the planar integration required in a multi-chip module. The filters presented here were designed for manufacture on a multi-layer liquid crystal polymer (LCP) substrate. A detailed trade study to assess the effects of potential manufacturing tolerances is presented. A framework for the automated creation of panelized design variations was developed using CAD tools. Thirty-two design variations with two different types of launches (microstrip and grounded co-planar waveguide) were successfully simulated, fabricated and tested, showing good electrical performance both as individual filters and cascaded to offer outstanding out-of-band rejection. The size of the new filters is 1 cm x 1 cm x 150 μm, a vertical reduction of over 90% and reducing the total cascaded length by over 50%

Study of solid-state integrated microwave circuits Scientific report no. 1, 15 Sep. - 14 Dec. 1965

Solid state microwave devices applied to integrated circuit

Analysis and Design of Low-Cost Waveguide Filters for Wireless Communications

The area of research of this thesis is built around advanced waveguide filter structures. Waveguide filters and the waveguide technology in general are renowned for high power capacity, low losses and excellent electromagnetic shielding. Waveguide filters are important components in fixed wireless communications as well as in satellite and radar systems. Furthermore, their advantages and utilization become even greater with increase in frequency, which is a trend in modern communication systems because upper frequency bands offer larger channel capacities. However, waveguide filters are relatively bulky and expensive. To comply with more and more demanding miniaturization and cost-cutting requirements, compactness and economical design represent some of the main contemporary focuses of interest. Approaches that are used to achieve this include use of planar inserts to build waveguide discontinuities, additive manufacturing and substrate integration. At the same time, waveguide filters still need to satisfy opposed stringent requirements like small insertion loss, high selectivity and multiband operation. Another difficulty that metal waveguide components face is integration with other circuitry, especially important when solid-state active devices are included. Thus, improvements of interconnections between waveguide and other transmission interfaces are addressed too. The thesis elaborates the following aspects of work: Further analysis and improved explanations regarding advanced waveguide filters with E-plane inserts developed by the Wireless Communications Research Group, using both cross coupled resonators and extracted pole sections (Experiments with higher filter orders, use of tuning screws, degrees of freedom in design, etc. Thorough performance comparison with competing filter technologies) - Proposing novel E-plane filter sections with I-shaped insets - Extension of the E-plane filtering structures with metal fins to new compact dual band filters with high frequency selectivity and miniaturized diplexers. - Introduction of easy-to-build waveguide filters with polymer insert frames and high-performance low-profile cavity filters, taking advantage of enhanced fabrication capabilities when using additive manufacturing - Developing new substrate integrated filters, as well as circuits used to transfer signals between different interfaces Namely, these are substrate integrated waveguide to metal waveguide planar transitions that do not require any modifications of the metal waveguides. Such novel transitions have been designed both for single and orthogonal signal polarizations

Design and analysis of wideband passive microwave devices using planar structures

A selected volume of work consisting of 84 published journal papers is presented to demonstrate the contributions made by the author in the last seven years of his work at the University of Queensland in the area of Microwave Engineering. The over-arching theme in the author’s works included in this volume is the engineering of novel passive microwave devices that are key components in the building of any microwave system. The author’s contribution covers innovative designs, design methods and analyses for the following key devices and associated systems: Wideband antennas and associated systems Band-notched and multiband antennas Directional couplers and associated systems Power dividers and associated systems Microwave filters Phase shifters Much of the motivation for the work arose from the desire to contribute to the engineering o

Development of turnable and miniature microwave filters for modern wireless communication

Due to the increasing demand for new wireless services and applications, the high level of integration and the coexistence of multi-standard (MS) or multi-band operations into a single device are becoming defining trends in designing microwave filters. This has driven considerable technological advances in reconfigurable/tunable and miniaturized filters. More specifically, reconfigurable/tunable filters that tune to different frequency bands instead of classical filter banks have great potential to significantly reduce the system size and complexity; while reducing the filter size becomes essential to achieve the highest degree of integration density in compact and portable wireless devices. In the light of this scenario, the objective of this dissertation is to develop the new design technologies, concepts and filtering configurations for tunable microstrip filters and compact passive microwave filters. To this aim, this dissertation is divided into two main parts. The first part (Part I) focuses on the designs of novel varactor-tuned microstrip filters with advanced performances. In this aspect, new topologies for realizing tunable lowpass and highpass filters are firstly developed. State-of-the-art performances, including wide tuning range, high selectivity with multiple transmission zeros, low insertion loss and compact size for all the tuning states are obtained in both of these filters. Secondly, two novel classes of tunable bandpass filters are presented. One of them is designed based on varactor-loaded parallel-coupled microstrip lines (PCML) and short-circuited stubs, which allows the lower passband edge together with two transmission zeros located around the lower passband skirt to be reconfigured separately. While the other tunable bandpass filter is iii constructed by the combination of tunable bandpass and lowpass filters, featuring both centre frequency and bandwidth tunabilities, as well as high selectivity with abundant transmission zeros. Furthermore, a new concept of tunable lossy filter is demonstrated, which attempts to achieve an equivalent high-Q tunable performance by using low-Q resonators. This concept makes the presented tunable combline filter interesting for some frequency-agile applications in which the low in-band loss variation and high selectivity are much desired while the absolute insertion loss can be a tradeoff. The second part (Part II) is devoted to the design of miniaturized passive microwave filters with improved characteristics. For this, the concept of artificial right-handed and left-handed transmission lines are applied to the signal interference filtering topology, which results in a compact circuit size and good out-of-band performance. In particular, for a further size reduction, such filter is implemented in the forms of multilayered structure by using liquid crystal polymer (LCP) technology. Additionally, another two types of miniaturized bandpass filters using stepped impedance resonators are demonstrated, which are implemented based on different fabrication processes (i.e. LCP bonded multilayer PCB technology and a standard planar PCB technology). Among their main features, the compact size, wide passband, broad stopband with multiple transmission zeros and circuit simplicity are highlighted. For all the proposed design techniques and filtering structures, exhaustive theoretical analyses are done, and design equations and guide rules are provided. Furthermore, all the proposed schemes and/or ideas have been experimentally validated through the design, implementation and measurement of different filters. The fabrication processes of multilayer technology utilized: liquid crystal polymer (LCP) technology and liquid crystal polymer (LCP) bonded multilayer printed circuit board (PCB) technology, are also demonstrated for reference. All of the results achieved in this dissertation make the proposed filters very attractive for their use in modern wireless communication systems.MultiWaves Project (PIRSES-GA-2010-247532) of the Seventh Framework Programme (FP7), European Commission

Development of tunable and miniature microwave filters for modern wireless communications

Due to the increasing demand for new wireless services and applications, the high level of integration and the coexistence of multi-standard (MS) or multi-band operations into a single device are becoming defining trends in designing microwave filters. This has driven considerable technological advances in reconfigurable/tunable and miniaturized filters. More specifically, reconfigurable/tunable filters that tune to different frequency bands instead of classical filter banks have great potential to significantly reduce the system size and complexity; while reducing the filter size becomes essential to achieve the highest degree of integration density in compact and portable wireless devices. In the light of this scenario, the objective of this dissertation is to develop the new design technologies, concepts and filtering configurations for tunable microstrip filters and compact passive microwave filters. To this aim, this dissertation is divided into two main parts. The first part (Part I) focuses on the designs of novel varactor-tuned microstrip filters with advanced performances. In this aspect, new topologies for realizing tunable lowpass and highpass filters are firstly developed. State-of-the-art performances, including wide tuning range, high selectivity with multiple transmission zeros, low insertion loss and compact size for all the tuning states are obtained in both of these filters. Secondly, two novel classes of tunable bandpass filters are presented. One of them is designed based on varactor-loaded parallel-coupled microstrip lines (PCML) and short-circuited stubs, which allows the lower passband edge together with two transmission zeros located around the lower passband skirt to be reconfigured separately. While the other tunable bandpass filter is constructed by the combination of tunable bandpass and lowpass filters, featuring both centre frequency and bandwidth tunabilities, as well as high selectivity with abundant transmission zeros. Furthermore, a new concept of tunable lossy filter is demonstrated, which attempts to achieve an equivalent high-Q tunable performance by using low-Q resonators. This concept makes the presented tunable combline filter interesting for some frequency-agile applications in which the low in-band loss variation and high selectivity are much desired while the absolute insertion loss can be a tradeoff. The second part (Part II) is devoted to the design of miniaturized passive microwave filters with improved characteristics. For this, the concept of artificial right-handed and left-handed transmission lines are applied to the signal interference filtering topology, which results in a compact circuit size and good out-of-band performance. In particular, for a further size reduction, such filter is implemented in the forms of multilayered structure by using liquid crystal polymer (LCP) technology. Additionally, another two types of miniaturized bandpass filters using stepped impedance resonators are demonstrated, which are implemented based on different fabrication processes (i.e. LCP bonded multilayer PCB technology and a standard planar PCB technology). Among their main features, the compact size, wide passband, broad stopband with multiple transmission zeros and circuit simplicity are highlighted. For all the proposed design techniques and filtering structures, exhaustive theoretical analyses are done, and design equations and guide rules are provided. Furthermore, all the proposed schemes and/or ideas have been experimentally validated through the design, implementation and measurement of different filters. The fabrication processes of multilayer technology utilized: liquid crystal polymer (LCP) technology and liquid crystal polymer (LCP) bonded multilayer printed circuit board (PCB) technology, are also demonstrated for reference. All of the results achieved in this dissertation make the proposed filters very attractive for their use in modern wireless communication systems

Analysis and Design of a Multifunctional Spiral Antenna

The Archimedean spiral antenna is well-known for its broadband characteristics with circular polarization and has been investigated for several decades. Since their development in the late 1950's, establishing an analytical expression for the characteristics of spiral antenna has remained somewhat elusive. This has been studied qualitatively and evaluated using numerical and experimental techniques with some success, but many of these methods are not convenient in the design process since they do not impart any physical insight into the effect each design parameter has on the overall operation of the spiral antenna. This work examines the operation of spiral antennas and obtains a closed-form analytical solution by conformal mapping and transmission line model with high precision in a wide frequency band. Based on the analysis of spiral antenna, we propose two novel design processes for the stripline-fed Archimedean spiral antenna. This includes a stripline feed network integrated into one of the spiral arms and a broadband tapered impedance transformer that is conformal to the spiral topology for impedance matching the nominally-high input impedance of the spiral. A Dyson-style balun located at the center facilitates the transition between guided stripline and radiating spiral modes. Measured and simulated results for a probe-fed design operating from 2 GHz to over 20 GHz are in excellent agreements to illustrate the synthesis and performance of a demonstration antenna. The research in this work also provides the possibility to achieve conformal integration and planar structural multi-functionality for an Unmanned Air Vehicle (UAV) with band coverage across HF, UHF, and VHF. The proposed conformal mapping analysis can also be applied on periodic coplanar waveguides for integrated circuit applications