The objective of this thesis work was to implement all the hardware and software necessary to simulate the functionality of a Vector Network Analyzer (VNA). With equipment that is already available, and is common in a measurement station, the most common functions of a VNA were implemented, using an Vector Signal Generator, that provide the signal for testing, and a Vector Signal Analyzer, to make all the amplitude and phase measurements. With these instruments and the appropriate software that control them, the basic functionality of a Vector Network Analyzer can be achieved with a reasonable accuracy. With this system, we can reduce costs, avoiding the need of a real VNA and take advantage off instruments that are already available in a laboratory. A Complete measurement system of all four scattering parameters is proposed at the end of the report for future implementation. With this implementation all the different S-parameter measurements were made with an acceptable accuracy that can be comparable to a commercial VNA.

In an attempt to provide a more secure and amiable living environment in our homes, there has been constant effort to develop more efficient and suitable intelligent sensor technology for household application. Wireless sensors provide an efficient means of sensing without the need for messy wiring, and are ideally suited for the household environment. Although many sensor products have been developed (e.g. temperature, humidity and smoke), automated detection and reporting of an incidence occurring in places hard to observe or reach, such as wetting of diapers or water seepage under carpets, are still not readily available at low cost. Most of the existing technologies consist of complex design architecture and follow specific communication protocols which can be overkill for many simple household applications. In this thesis, we present a new wireless sensor system which is based on the detection of just the ON or OFF state of a condition. This approach overcomes the need for complex architecture and design, but is still able to achieve the functionality that is required for many household applications such as water leakage, food rotting, diaper wetting etc. and thus can be made available very cheaply. The sensor system consisting of an interrogator and a sensor circuit is implemented using inductive coupling. A passive L-C circuit is used for the sensor design and the system is tested using diaper wetting as an example of a simple household application. The testing results shows that the sensor can detect an ON and OFF condition for sensor and tag separation of 10 cm which is enough for applications like water leakage behind walls and under carpets, diaper wetting, food rotting etc.

El ràpid creixement dels sistemes de telecomunicacions sense fils ha portat a una creixent demanda de dispositius mòbils amb requisits cada vegada més estrictes per als filtres de microones incloent un millor rendiment, miniaturització i la reducció de costos. Una nova tecnologia de filtres de RF s’ha consolidat en l'última dècada: la tecnologia BAW. Els filtres BAW són perfectament adequats com a filtres miniaturitzats i d'alt rendiment per a aplicacions d'alta freqüència. En comparació amb la tecnologia SAW, els filtres BAW proporcionen menors pèrdues d'inserció, una millor selectivitat, compatibilitat CMOS, millor maneig de potència i una major freqüència de treball. Un CRF BAW és un dels més recents filtres BAW que permet oferir una àmplia gamma de noves i interessants propietats en comparació dels seus predecessors. Basat en el concepte de ressonadors acoblats acústicament, es poden oferir respostes Chebyshev clàssiques i avançades, millor ample de banda, més miniaturització i conversió de mode. La complexitat d'un CRF és considerable en termes de disseny i fabricació, a causa de la quantitat de làmines que el conformen. El disseny de filtres BAW es basa en dimensionar les capes del dispositiu. El disseny és complex i els procediments d'optimització poden no ser eficients a causa de la quantitat de variables que intervenen en el procés. En aquest treball es presenta una metodologia d'anàlisi i síntesi. Les tècniques poden fer front a les estructures de diverses capes d'una manera directa. Es presenta un conjunt de models circuitals completament elèctrics que simplifiquen i recullen el comportament dels CRF, dispositius que funcionen tant en els dominis elèctric i mecànic. S'han establert un conjunt d'eines per analitzar el ressonador per mitjà de teoria de xarxes i és la base per a l'anàlisi d'estructures compostes de diversos ressonadors i múltiples capes de làmines primes. Es desenvolupa un model per al CRF utilitzant transformacions de xarxa i aproximacions respecte a les freqüències de funcionament dels dispositius BAW. Es presenta un anàlisi profund del BAW CRF amb els models proposats com una eina que permet guiar el procediment analític. L'anàlisi dels filtres facilita una millor comprensió del seu funcionament i una manera d'establir els límits de les respostes que poden oferir. Es presenten metodologies de disseny de filtres amb la finalitat d'obtenir les geometries de l'estructura i la topologia dels filtres BAW per complir amb les respostes prescrites. El disseny del filtre es dona a partir d'una comprensió clara dels seus mecanismes de filtratge de manera que facilita l'explotació de les seves característiques inherents. Les respostes avançades amb zeros de transmissió o els filtres de banda de rebuig procedents dels nous dispositius presentats es sintetitzen per mitjà de les metodologies proposades. / El rápido crecimiento de los sistemas de telecomunicaciones inalámbricas ha llevado a una creciente demanda de dispositivos móviles con requisitos cada vez más estrictos para los filtros de microondas incluyendo un mejor rendimiento, miniaturización y la reducción de costes. Una nueva tecnología de filtros de RF se ha consolidado en la última década: la tecnología BAW. Los filtros BAW son perfectamente adecuados como filtros miniaturizados y de alto rendimiento para aplicaciones de alta frecuencia. En comparación con la tecnología SAW, los filtros BAW proporcionan menores pérdidas de inserción, una mejor selectividad, compatibilidad CMOS, mejor manejo de potencia y una mayor frecuencia de trabajo. Un CRF BAW es uno de los más recientes filtros BAW que permite ofrecer una amplia gama de nuevas e interesantes propiedades en comparación con sus predecesores. Basado en el concepto de resonadores acoplados acústicamente, se pueden ofrecer respuestas Chebyshev clásicas y avanzadas, mejor ancho de banda, más miniaturización y conversión de modo. La complejidad de un CRF es considerable en términos de diseño y fabricación, debido a la cantidad de láminas que lo conforman. El diseño de filtros BAW se basa en dimensionar las capas del dispositivo. El diseño es complejo y los procedimientos de optimización pueden no ser eficientes debido a la cantidad de variables que intervienen en el proceso. En este trabajo se presenta una metodología de análisis y síntesis. Las técnicas pueden hacer frente a las estructuras de varias capas de una manera directa. Se presenta un conjunto de modelos circuitales completamente eléctricos que simplifican y recogen el comportamiento de los CRF, dispositivos que funcionan tanto en los dominios eléctrico y mecánico. Se han establecido un conjunto de herramientas para analizar el resonador mediante teoría de redes y es la base para el análisis de estructuras compuestas de varios resonadores y múltiples capas de láminas delgadas. Se desarrolla un modelo para el CRF utilizando transformaciones de red y aproximaciones respecto a las frecuencias de funcionamiento de los dispositivos BAW. Se presenta un análisis profundo del BAW CRF con los modelos propuestos como una herramienta que permite guiar el procedimiento analítico. El análisis de los filtros facilita una mejor comprensión de su funcionamiento y una manera de establecer los límites de las respuestas que pueden ofrecer. Se presentan metodologías de diseño de filtros con el fin de obtener las geometrías de la estructura y la topología de los filtros BAW para cumplir con las respuestas prescritas. El diseño del filtro se da a partir de una comprensión clara de sus mecanismos de filtrado de modo que facilita la explotación de sus características inherentes. Las respuestas avanzadas con ceros de transmisión o los filtros de banda de rechazo procedentes de los nuevos dispositivos presentados se sintetizan por medio de las metodologías propuestas. / The speedy growth of wireless telecommunication systems has led to an increasing demand for hand-held devices with more and more stringent requisites for microwave filters including better performance, miniaturization and reduced costs. A new RF filter technology has emerged during the last decade: BAW technology. BAW filters are perfectly suitable as miniaturized high performance filters for high frequency and power applications. Compared to SAW filter technology, BAW filter solutions can provide lower insertion loss, better selectivity, CMOS compatibility, higher power handling and higher operation frequency.A BAW CRF is one of the latest BAW filter topologies to offer a range of new and interesting properties compared to its predecessors. Based on the concept of acoustically coupled resonators, it can provide classical and advanced Chebyshev responses, better bandwidths, more miniaturization and mode conversion. The complexity of a CRF is considerable in terms of design and fabrication due to the quantity of films that it comprises.The design of BAW filters is based on sizing the layers of the physical device. It becomes complicated with this amount of layers, and optimization procedures may not be efficient due to the number of variables involved in the process. A methodology to analyze and synthesize BAW CRFs is presented in this work. The techniques can deal with multilayered structures in a straightforward way.A set of fully electric circuital models that simplify and gather the behavior of CRFs, devices that work both in the electrical and the mechanical domains, are presented. A set of tools to analyze the resonator by means of network theory is established and is the basis for analyzing structures composed of several resonators and multiple thin-film layers. A model for the most basic CRF is developed using network transformations and approximations regarding the frequencies of operation of the BAW devices.A profound analysis of BAW CRFs is presented using the proposed models as an enabling tool to guide the analytical procedure. The analysis of those filters facilitates a better understanding of their performance and a way to establish the limits on the responses that they can provide. Systematic filter design methodologies are presented in order to obtain the structure geometries and topologies of BAW filters to fulfill prescribed responses in such a way that fully time-consuming and sometimes not very controlled optimization-oriented procedures are avoided. The design of the filter from a clear understanding of its performances facilitates the exploitation of its inherent characteristics. Advanced responses with transmission zeros or stopband filters coming from new devices are synthesized by means of the proposed methodologies.

Microwave and millimeter wave switch matrices are essential components in telecommunication systems. These matrices enhance satellite capacity by providing full and flexible interconnectivity between the received and transmitted signals and facilitate optimum utilization of system bandwidth. Waveguide and semiconductor technology are two prominent candidates for the realizing such types of switch matrices. Waveguide switches are dominant in high frequency applications of 100 ? 200 GHz and in high power satellite communication. However, their heavy and bulky profile reinforces the need for a replacement. In some applications, semiconductor switches are an alternative to mechanical waveguide switches and utilize PIN diodes to create the ON and OFF states. Although, these switches are small in size, they exhibit poor RF performance and low power handling. <br /><br /> RF MEMS technology is a good candidate to replace the conventional switches and to realize an entire switch matrix. This technology has a great potential to offer superior RF performance with miniaturized dimensions. Because of the advantages of MEMS technology numerous research studies have been devoted to develop RF MEMS switches. However, they are mostly concentrated on Single-Pole Single-Throw (SPST) configurations and very limited work has been performed on MEMS multi-port switches and switch matrices. Here, this research has been dedicated on developing multi-port RF MEMS switches and amenable interconnect networks for switch matrix applications. To explore the topic, three tasks are considered: planar (2D) multi-port RF MEMS switches, 3D multi-port RF MEMS switches, and RF MEMS switch matrix integration. <br /><br /> One key objective of this thesis is to investigate novel configurations for planar multi-port (SPNT), C-type, and R-type switches. Such switches represent the basic building blocks of switch matrices operating at microwave frequencies. An in house monolithic fabrication process dedicated to electrostatic multi-port RF MEMS switches is developed and fine tuned. The measurement results exhibit an excellent RF performance verifying the concept. Also, thermally actuated multi-port switches for satellite applications are designed and analyzed. The switch performance at room condition as well as at a very low temperature of 77K degrees (to resemble the harsh environment of satellite applications) is measured and discussed in detail. <br /><br /> For the first time, a new category of 3D RF MEMS switches is introduced to the MEMS community. These switches are not only extremely useful for high power applications but also have a great potential for high frequencies and millimetre-waves. The concept is based on the integration of vertically actuated MEMS actuators inside 3D transmission lines such as waveguides and coaxial lines. An SPST and C-type switches based on the integration of rotary thermal and electrostatic actuators are designed and realized. The concept is verified for the frequencies up to 30GHz with measured results. A high power test analysis and measurement data indicates no major change in performance as high as 13W. <br /><br /> The monolithic integration of the RF MEMS switch matrix involves the design and optimization of a unique interconnect network which is amenable to the MEMS fabrication process. While the switches and interconnect lines are fabricated on the front side, taking advantage of the back side patterning provides a high isolation for cross over junctions. Two different techniques are adopted to optimize the interconnect network. They are based on vertical three-via interconnects and electromagnetically coupled junctions. The data illustrates that for a return loss of less than -20dB up to 30GHz, an isolation of better than 40dB is obtained. This technique not only eliminates the need for expensive multilayer manufacturing process such as Low Temperature Co-fired Ceramics (LTCC) but also provides a unique approach to fabricate the entire switch matrix monolithically.

High performance inductors are playing an increasing role in modern communication systems. Despite the superior performance offered by discrete components, parasitic capacitances from bond pads, board traces and packaging leads reduce the high frequency performance and contribute to the urgency of an integrated solution. Embedded inductors have the potential for significant increase in reliability and performance of the IC. Due to the driving force of CMOS integration and low costs of silicon-based IC fabrication, these inductors lie on a low resistivity silicon substrate, which is a major source of energy loss and limits the frequency response. Therefore, the quality factor of inductors fabricated on silicon continues to be low. The research presented in this thesis investigates amorphous Si and porous Si to improve the resistivity of Si substrates and explores amorphous Si as a structural material for low temperature MEMS fabrication. Planar inductors are built-on undoped amorphous Si in a novel application and a 56% increase in quality factor was measured. Planar inductors are also built-on a porous Si and amorphous Si bilayer and showed 47% improvement. Amorphous Si is also proposed as a low temperature alternative to polysilicon for MEMS devices. Tunable RF MEMS inductors and transformers are fabricated based on an amorphous Si and aluminum bimorph coil that is suspended and warps in a controllable manner. The 3-D displacement is accurately predicted by thermomechanical simulations. The tuning of the devices is achieved by applying a DC voltage and due to joule heating the air gap can be adjusted. A tunable inductor with a 32% tuning range from 5.6 to 8.2 nH and a peak Q of 15 was measured. A transformer with a suspended coil demonstrated a 24% tuning range of the mutual coupling between two stacked windings. The main limitation posed by post-CMOS integration is a strict thermal budget which cannot exceed a critical temperature where impurities can diffuse and materials properties can change. The research carried out in this work accommodates this temperature restriction by limiting the RF fabrication processes to 150°C to facilitate system integration on silicon.

In today’s communication devices, the need for high performance inductors is increasing as they are extensively used in RF integrated circuits (RFICs). This need is even more pronounced for variable inductors as they are widely required in tunable filters, voltage controlled amplifiers (VCO) and low noise amplifiers (LNA). For RFICs, the main tuning elements are solid state varactors that are used in conjunction with invariable inductors. However, they have limited linearity, high resistive losses, and low self resonant frequencies. This emphasizes the need for developing another tuning element that can be fabricated monolithically with ICs and can offer high range of tuning. Due to the ease of CMOS integration and low cost silicon based IC fabrication, the inductors currently used are a major source of energy loss, therefore driving the overall quality factor and performance of the chip down. During the last decade there has been an increase in research in RF MicroelectroMechanical Systems (RF MEMS) to develop high quality on chip tunable RF components. MEMS capacitors were initially proposed to substitute the existing varactors, however they can not be easily integrated on top of CMOS circuits. RF MEMS variable inductors have recently attracted attention as a better alternative. The research presented here explores using porous anodic alumina (PAA) in CMOS and MEMS fabrication. Due to its low cost and low temperature processing, PAA is an excellent candidate for silicon system integration. At first, PAA is explored as an isolation layer between the inductor and the lossy silicon substrate. Simulations show that although the dielectric constant of the PAA is tunable, the stress produced by the required thicker layers is problematic. Nevertheless, the use of PAA as a MEMS material shows much more promise. Tunable RF MEMS inductors based on bimorph sandwich layer of aluminum PAA and aluminum are fabricated and tested. A tuning range of 31% is achieved for an inductance variation of 5.8 nH to 7.6 nH at 3 GHz. To further improve the Q, bimorph layers of gold and PAA are fabricated on Alumina substrates. A lower tuning range is produced; however the quality factor performance is greatly improved. A peak Q of over 30 with a demonstrated 3% tuning range is presented. Depending on the need for either high performance or tunability, two types of tunable RF MEMS inductors are presented. Although PAA shows promise as a mechanical material for MEMS, the processing parameters (mainly stress and loss tangent) need to be improved if used as an isolation layer. To our knowledge, this is the first time this material has been proposed and successfully used as a structural material for MEMS devices and CMOS processes.

To obtain the power levels required from high RF power transistors, the size of the chip has often to be made so large that inductance of electrical connections inside the package cannot be neglected. This may have the effect that various parts of the transistor chip are not connected exactly parallel, i.e. drain and gate voltages and currents densities will not be the same on different parts of the chip. This may result in degraded output power and efficiency. The same effect may occur when more than one chip are connected in parallel in a transistor package to obtain even higher output power.Often the connections to the transistor package are approximated as a number of electrical point connections (normally three: gate, drain, source); meaning that each of them can be described by a single electrical potential and current. In reality, they may be large enough that voltage and current distributions have to be considered. These distributions will be affected by different mountings of the transistor and other connected components.In this work, the LDMOS power transistor MRF6S21140HR3 was modeled using the segmentation method in high frequency signal simulation HFSS which is a 3D Full-Wave Electromagnetic Field Simulation, and utilized the advanced design system ADS to find a parameterized lumped model. Both the electromagnetic and lumped models showed consistent results. Non-ideal parallel connection of sub-transistors on chip is very important, but further studies are needed for definite conclusion. It was verified through modeling that non ideal parallel connection of different chips in the package does have an effect; the effect however is quiet small which proves that the signal is slightly non-uniformly distributed between the three chips in the package. External connection to PCB (drain connection is considered in this work) can effectively be taken as a point connection to some approximation. The electrical behavior of the modeled transistor was studied through the design of a class B power amplifier in order to estimate the importance of performance degradation due to non-ideal parallel connections and how these non ideal connections degrade efficiency and output power. The modeled transistor can deliver a maximum output power of 147 watts and efficiency of 65%. We have also studied the current distribution between the three chips in a three stage class B power amplifier. Again, the difference in the current distribution between the three chips turned out to be quiet small. All these results are presented through this work. The final conclusion regarding the current distribution between multichips cannot be made just based on these simulation results. The next step should be aimed at considering other effects, the thermal effect for example, in order to know exactly whether it is uniformly or not uniformly distributed.

The thesis purpose is to be implementing a system where a sweeping signal generator connected to a scalar network analyzer (SNA). The SNA is a less complicated that the VNA and normally much cheaper. Between these two instruments only the cable fro synchronization between then needed. The synchronization signal is simply low frequency saw tooth signal not so sensitive for disturbance as RF signal. Therefore a very simple cable can be used.

In this thesis work, a design of RF down-conversion mixer for WLAN standard, such as Wi-Fi or Bluetooth is presented. The target technology is 0.35um CMOS process. Several mixer topologies are analyzed and simulated at the schematic level using the Cadence Spectre-RF software. The active double balanced mixer is chosen for the ultimate implementation. For this mixer simulation results from schematic level to layout level are presented and discussed in detail. To build an RF front-end, the complete mixer is integrated with an available LNA block. The performance of the front-end is evaluated as well. The obtained simulation results satisfy the specification for Wi-Fi standard. Since the RF front-end is designed for testability, the fault simulation is incorporated as well. So the performance of the front end is also evaluated for so called “spot defects”, typical of CMOS technology. They are modeled using resistive shorts or opens in the circuit.

Microwave and millimeter wave switch matrices are essential components in telecommunication systems. These matrices enhance satellite capacity by providing full and flexible interconnectivity between the received and transmitted signals and facilitate optimum utilization of system bandwidth. Waveguide and semiconductor technology are two prominent candidates for the realizing such types of switch matrices. Waveguide switches are dominant in high frequency applications of 100 ? 200 GHz and in high power satellite communication. However, their heavy and bulky profile reinforces the need for a replacement. In some applications, semiconductor switches are an alternative to mechanical waveguide switches and utilize PIN diodes to create the ON and OFF states. Although, these switches are small in size, they exhibit poor RF performance and low power handling. <br /><br /> RF MEMS technology is a good candidate to replace the conventional switches and to realize an entire switch matrix. This technology has a great potential to offer superior RF performance with miniaturized dimensions. Because of the advantages of MEMS technology numerous research studies have been devoted to develop RF MEMS switches. However, they are mostly concentrated on Single-Pole Single-Throw (SPST) configurations and very limited work has been performed on MEMS multi-port switches and switch matrices. Here, this research has been dedicated on developing multi-port RF MEMS switches and amenable interconnect networks for switch matrix applications. To explore the topic, three tasks are considered: planar (2D) multi-port RF MEMS switches, 3D multi-port RF MEMS switches, and RF MEMS switch matrix integration. <br /><br /> One key objective of this thesis is to investigate novel configurations for planar multi-port (SPNT), C-type, and R-type switches. Such switches represent the basic building blocks of switch matrices operating at microwave frequencies. An in house monolithic fabrication process dedicated to electrostatic multi-port RF MEMS switches is developed and fine tuned. The measurement results exhibit an excellent RF performance verifying the concept. Also, thermally actuated multi-port switches for satellite applications are designed and analyzed. The switch performance at room condition as well as at a very low temperature of 77K degrees (to resemble the harsh environment of satellite applications) is measured and discussed in detail. <br /><br /> For the first time, a new category of 3D RF MEMS switches is introduced to the MEMS community. These switches are not only extremely useful for high power applications but also have a great potential for high frequencies and millimetre-waves. The concept is based on the integration of vertically actuated MEMS actuators inside 3D transmission lines such as waveguides and coaxial lines. An SPST and C-type switches based on the integration of rotary thermal and electrostatic actuators are designed and realized. The concept is verified for the frequencies up to 30GHz with measured results. A high power test analysis and measurement data indicates no major change in performance as high as 13W. <br /><br /> The monolithic integration of the RF MEMS switch matrix involves the design and optimization of a unique interconnect network which is amenable to the MEMS fabrication process. While the switches and interconnect lines are fabricated on the front side, taking advantage of the back side patterning provides a high isolation for cross over junctions. Two different techniques are adopted to optimize the interconnect network. They are based on vertical three-via interconnects and electromagnetically coupled junctions. The data illustrates that for a return loss of less than -20dB up to 30GHz, an isolation of better than 40dB is obtained. This technique not only eliminates the need for expensive multilayer manufacturing process such as Low Temperature Co-fired Ceramics (LTCC) but also provides a unique approach to fabricate the entire switch matrix monolithically.