The design and fabrication of miniature microwave bandpass filters using multilayer liquid crystal polymer technology

This thesis presents the design and fabrication techniques for miniature microwave bandpass filters using multilayer liquid crystal polymer (LCP) technology. As a multilayer technology for microwave devices, LCP is of low cost and light weight. It also has excellent electrical properties across a wide frequency range. These characteristics make it promising for the development of next generation microwave devices for applications across commercial, defence and civil sectors. However, very limited work has been found in the open literature to apply this technology to the design of miniature bandpass filters, especially at low microwave frequencies. In addition, the reported work shows lack of fabrication techniques, which limits the size reduction of multilayer LCP devices. To address these problems, this thesis develops advanced fabrication techniques for sophisticated LCP structures, such as multilayer capacitors, via connections and cavities. These techniques are then used to support the design of novel miniature bandpass filters for wideband and narrowband applications. For the design of miniature wideband bandpass filters, a cascaded approach, which combines highpass and lowpass filters, is presented first to provide a flexible design solution. This is followed by another novel ultra-wideband bandpass filter which produces extra transmission zeroes with minimum number of elements. It does not only have high performance but also a compact structure for high yield fabrication. For narrowband applications, two types of advanced coupled-resonator filters are developed. One type produces a very good selectivity at the upper passband edge, and its spurious-free stopband is extremely wide and of high interference attenuation. The other type, based on novel mixed-couplings approaches developed in this thesis, provides a solution to produce almost the same response as the coupling matrix prototype. This type is used to generate arbitrarily-located transmission zeroes. All designs presented in this thesis are simulated using CAD design tools and then validated by measurements of fabricated samples. Good agreements between simulations and measurements are shown in the thesis

LTCC low phase noise voltage controlled oscillator design using laminated stripline resonators.

Cheng Sin-hang.Thesis (M.Phil.)--Chinese University of Hong Kong, 2002.Includes bibliographical references (leaves 90-92).Abstracts in English and Chinese.Chapter Chapter 1 --- Introduction --- p.1Chapter Chapter 2 --- Theory of Oscillator Design --- p.4Chapter 2.1 --- Open-loop approach --- p.4Chapter 2.2 --- One-port approach --- p.6Chapter 2.3 --- Two-port approach --- p.9Chapter 2.4 --- Voltage controlled oscillator (VCO) design --- p.10Chapter 2.4.1 --- Active device selection and biasing --- p.11Chapter 2.4.2 --- Feedback circuit design --- p.15Chapter 2.4.3 --- Frequency tuning circuit --- p.20Chapter Chapter 3 --- Noise in Oscillators --- p.23Chapter 3.1 --- Origin of phase noise --- p.23Chapter 3.2 --- Impact of phase noise in communication system --- p.28Chapter 3.3 --- Phase noise consideration in VCO design --- p.30Chapter Chapter 4 --- Low Temperature Co-Fired Ceramic --- p.31Chapter 4.1 --- LTCC process --- p.31Chapter 4.1.1 --- LTCC fabrication process --- p.32Chapter 4.1.2 --- LTCC materials --- p.34Chapter 4.1.3 --- Advantages of LTCC technology --- p.35Chapter 4.2 --- Passive components realization in LTCC --- p.37Chapter 4.2.1 --- Capacitor --- p.37Chapter 4.2.2 --- Inductor --- p.42Chapter Chapter 5 --- High-Q LTCC Resonator Design --- p.47Chapter 5.1 --- Definition of Q-factor --- p.47Chapter 5.2 --- Stripline --- p.50Chapter 5.3 --- Power losses --- p.52Chapter 5.4 --- Laminated stripline resonator design --- p.53Chapter 5.4.1 --- λ/4 resonator structure --- p.57Chapter 5.4.2 --- Meander-line resonator structure --- p.60Chapter 5.4.3 --- Bi-metal-layer resonator structure --- p.63Chapter Chapter 6 --- LTCC Voltage Controlled Oscillator Design --- p.67Chapter 6.1 --- Circuit design --- p.67Chapter 6.2 --- Output filter --- p.68Chapter 6.3 --- Embedded capacitor --- p.71Chapter 6.4 --- VCO layout and simulation --- p.72Chapter Chapter 7 --- Experimental Setup and Results --- p.77Chapter 7.1 --- Measured Result: LTCC resonators --- p.77Chapter 7.1.1 --- Experimental results --- p.79Chapter 7.2 --- Measured results: LTCC voltage controlled oscillators --- p.83Chapter Chapter 8 --- Conclusion and Future Work --- p.88Reference List --- p.90Appendix A: TRL calibration method --- p.93Appendix B: Q measurement --- p.103Appendix C: Q-factor extraction program listing --- p.109Chapter 1. --- Function used to calculate Q from s-parameter --- p.109Chapter 2. --- Function used to calculate Q from z-parameter --- p.11

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

Modelling of Stratified Dielectric Medium Stripline Delay Devices

Problem of investigation of stripline delay devices in stratified dielectric medium is considered in the dissertation. In the first chapter scientific publications regarding modelling of stripline delay devices and microwave devices in planar stratified dielectric medium, issued from 1976 to 2014 year are analytically reviewed. Areas of applications, methods of analysis and design and problems in modelling and design are analyzed. In the second chapter models of coupled and multiconductor microstrip lines in nonhomogenous dielectric medium are analyzed. Conditions for ensuring normal wave propagation in the lines are researched. Such lines can serve as the basis for stripline meander delay line modelling. The possibilities of equalizing phase velocities for odd and even normal wave propagation in coupled striplines in stratified dielectric medium are analyzed. The effect of air microlayer in double shielded stripline devices is reseached by using the created model. Techniques for synthesis, i.e. obtaining constructional parameters according to the desired electrical characteristics of multiconductor microstrip lines operating in even and odd normal mode have been created and researched. The proposed technique is based on iterative calculation of characterisitics by changing parameters, until the desired characteristic value is obtained. Effect of equalizing phase velocities of electromagnetic wave in strips of microstrip meander delay line to frequency characteristics have been investigated. Meander delay line based on the multiconductor line operating in even mode was designed and its characteristics were calculated using commercial software. Influence of air microlayer in packaged double shielded meander stripline delay line has been investigated. The delay line was designed and its characteristics were calculated by two different techniques – the proposed modelling technique combined with S-matrix method and modelled with comercial software based on the method of moments. A prototype double shielded meander delay line has been produced and its characteristics have been measured in order to check the correctness of the model. Comparisson of calculations and measurement differed by no more than 2%

Miniaturization of Microstrip Bandpass Filters Using Multilayer Configuration for Wideband Application

This thesis presents new designs of wideband bandpass filter for X-band application using various resonator configurations in multilayer microstrip. Strong coupling required for wideband filter is realized by arranging multiple layers of microstrip lines on different dielectric substrates and overlapping these lines. For the first design, half wavelength coupled lines resonator is used to design wideband X-band bandpass filter, and the resonator is rotated to make the filter more compact. The measured passband return loss for this filter is better than -12.4 dB and the insertion loss is less than 2.5 dB. For second design, microstrip hairpin resonator is employed to build the miniaturized bandpass filter. Since adjacent hairpin resonator lines are placed at different levels, there are two possible ways to change coupling strength by varying the overlapping gap between two resonators; vertically and horizontally. Both have different benefit, one can reduce the filter length, and obtain symmetrical response. The other can reduce filter width, giving sharper rejection at high frequency. Both configurations produce very small and compact filter size, at 5.0 x 14.6 mm2 and 3.2 x 16.1 mm2 for the first and second proposed filter type respectively. The measured passband insertion loss for both filters are less than 2.3 dB and the passband return loss is better than -16 dB for the first filter type and -13 dB for the second filter type. Multilayer configuration gives freedom to choose any resonator shape and combine with another shape to make the filter in very compact size. For the last design in this thesis, hairpin resonator has been combined with half wavelength coupled lines resonator in multilayer configuration. Both different resonator shapes are placed on two different substrates with different dielectric constants, whereby the hairpin resonators are placed on the bottom layer and the straight line resonators are placed on the upper layer. The hybrid between hairpin resonator and half wavelength coupled lines configuration has made the filter even more compact and produce a very small filter size, only at 10 x 10 mm2. The measured passband return loss for this filter is better than -12.5 dB and the insertion loss is less than 2.3 dB. All of the filters are fabricated on 0.254 mm thickness R/T Duroid 6010 and R/T Duroid 5880 with dielectric constant 10.2 and 2.2 respectively using standard photolithography technique. Two layers of substrate are joined using epoxy adhesion which has dielectric constant of 3.6. This epoxy layer is included in simulation. Broader bandwidth produced by those filter configurations are proven able to cover the whole X-band frequencies of 44% bandwidth at 10.2 GHz center frequency with excellent Chebyshev responses. The measured results agree well with the simulated responses. The measured responses and group delay exhibit that all of designed filters have good performance

Heterogeneous Integration of RF and Microwave Systems Using Multi-layer Low-Temperature Co-fired Ceramics Technology

[eng] The aim of this work is the development of a modelling methodology for the fast analysis of non-radiative multilayer RF passive components without compromising solution accuracy. Instead of following a compact model approach, oftenly used in integrated technologies, the method is based on a specialized quasi-static partial element equivalent circuit (PEEC) numerical solver. Besides speed and accuracy, the solver can be embedded in circuit simulators; thus, models are already available in the schematic entry. Using this framework, model scalability is enhanced in terms of geometry, substrate cross-section, material properties, topology and boundary conditions. The dissertation starts showing the actual performance of the obtained solver and the motivations beneath its development. Then, the description about solver development is splitted in three parts, but all of them are interrelated. First, the PEEC formulation is adapted according to relevant electromagnetic behaviour of the component. It is worth stressing that a different perspective related to the principle of virtual work is used in this formulation. The second part deals with the evaluation of partial elements, the core of the solver. It is carried out using analytical space-domain close-form solutions of the Green’s function (GF) of the substrate. Partial elements are then assembled into a mesh. Therefore, the importance of the mesh up on solution accuracy is discussed in the last part and a basic layout aware mesh generator is proposed. Practical application of the methodology includes the implementation of a library of RF passives for multilayer substrate. For validation, the chosen substrate is a low temperature co-fired ceramics (LTCC) technology. Different set of devices have been fabricated, characterized and compared against model prediction. In addition, the obtained results are also verified using state-of-the-art electromagnetic solvers.[spa] El objetivo de este trabajo es el desarrollo de una metodología de modelado para el análisis rápido, pero sin comprometer la precisión de la solución, de componentes pasivos no radiativos de RF en substratos multicapa. El método se basa en el algoritmo numérico cuasi-estático de los elementos parciales de circuito equivalente (PEEC). Éste puede ser incorporado en simuladores de circuitos; por tanto, los modelos ya están disponibles en la entrada de esquemático de forma transparente para el diseñador de circuitos. Utilizando este marco, la escalabilidad del modelo se mejora en términos de la geometría, la definición del corte tecnológico, las propiedades del material, la topología del componente y las condiciones de contorno electro-magnéticas. Esta disertación comienza mostrando las motivaciones que han llevado a su desarrollo y la capacidad real del método de resolución obtenido. A partir de aquí, se realiza la descripción de todo el desarrollo del marco numérico que se divide en tres partes que están interrelacionadas. En primer lugar, la formulación PEEC se adapta según el comportamiento electromagnético real del componente. Vale la pena subrayar que en esta formulación se utiliza una perspectiva diferente a la habitual y que está relacionada con el principio de los trabajos virtuales de d’Alembert. La segunda parte trata de cómo se evalúan los elementos parciales y constituye el núcleo principal del algoritmo. Se lleva a cabo utilizando soluciones analíticas de la función de Green (GF) del sustrato en el dominio espacial. Los elementos parciales, que forman la malla numérica del modelo, se ensamblan en la matriz del sistema siguiendo un procedimiento de análisis nodal modificado (MNA). En la última parte, se discute la importancia de la malla sobre la precisión de la solución y se propone un generador de malla basado en la física del componente y no sólo en la descripción de la geometría. Como aplicación práctica de la metodología, se realiza la generación de una biblioteca de componentes pasivos RF para sustratos multicapa

Design, Modelling and Implementation of Several Multi-Standard High Performance Single-Wideband and Multi-Wideband Microwave Planar Filters

The objectives of this work are to review, investigate and model the microwave planar filters of the modern wireless communication system. The recent main stream of microwave filters are classified and discussed separately. Various microwave filters with detailed applications are investigated in terms of their geometrical structures and operational performances. A comprehensive theoretical study of microwave filters is presented. The main types of microwave filters including the basic low-pass filters such as Butterworth and Chebyshev filters are fully analysed and described in detail. The transformation from low-pass prototype filters to high-pass filters, band-pass filters and band-stop filters are illustrated and introduced. Research work on stepped impedance resonator (SIR) and asymmetric stepped impedance resonator (ASIR) structure is presented. The characteristics of λg/4, λg/2 and λg (λg is the guided wavelength of the fundamental frequency in the free space) type SIR resonators, and the characteristic of asymmetric SIR resonator are categorized and investigated. Based on the content mentioned above, novel multi-standard high performance asymmetric stepped impedance resonator single-wideband and dual-wideband filters with wide stopbands are proposed. The methodologies to realize wide passband and wide stop-band filters are detailed. In addition, multi-standard high performance triplewideband, quadruple-wideband and quint-wideband filters are suggested and studied. The measurement results for all prototype filters agree well with the theoretical predictions and simulated results from Ansoft HFSS software. The featured broad bandwidths over single/multiple applicable frequency bands and the high performances of the proposed filters make them very promising for applications in future multistandard wireless communication

DESIGN AND ANALYSIS OF ANTENNA-ON-CHIP AND ANTENNA-IN-PACKAGE FOR 60-GHZ WIRELESS COMMUNICATIONS

Ph.DDOCTOR OF PHILOSOPH