A new active LO phase shifter was introduced and implemented in a 2x2 wide band MIMO receiver. The chip was designed with STMicroelectronics 90nm technology. The main advantages of the proposed phase shifter over previous works included a wide band range, high resolution and small area. The phase shifter is based on the dependency of the inverter propagation delay on the load capacitance. Simply, by changing the load capacitance of an inverter, a different propagation delay is generated. A number of these controllable delay cells are cascaded to provide the required phase-shift. In order for the delay cells to reduce the required amount of phase-shifting the I&Q swap circuit is introduced. The I&Q swap circuitry reduces the phase-shifting by one fourth of the original range. The wide band phase shifter is suitable for multi-standard radios, since just one phase shifter is needed to support all standards. This capability of the phase shifter could potentially reduce the size of the die and simplify the design. The measurement shows that the phase shifter is able to provide 360˚ of phase-shifting at the output base band signal when the LO is varying from 1.5GHz to 6GHz. A wider range of the phase shifter is achievable by reducing the capacitance load and increasing the number of cascaded delay cells. The proposed phase shifter is capable of achieving a very high resolution. The resolution of the phase shifter is a function of the inverter current capability and the load capacitance. The measurements show the average resolution of the proposed phase shifter is about 1.32ps. Passive components usually take up a large area on the chip. A MOS capacitor is used as the load to reduce the area of the proposed phase shifter. A method is proposed to improve the phase shifter stability over the temperature and process variations. This method is based on the fact that the propagation delay of an inverter is inversely proportional to the power supply. Therefore, the phase shifters’ power supply must be varied to maintain a relatively constant phase shifter resolution over the temperature and process variations.

A new active LO phase shifter was introduced and implemented in a 2x2 wide band MIMO receiver. The chip was designed with STMicroelectronics 90nm technology. The main advantages of the proposed phase shifter over previous works included a wide band range, high resolution and small area. The phase shifter is based on the dependency of the inverter propagation delay on the load capacitance. Simply, by changing the load capacitance of an inverter, a different propagation delay is generated. A number of these controllable delay cells are cascaded to provide the required phase-shift. In order for the delay cells to reduce the required amount of phase-shifting the I&Q swap circuit is introduced. The I&Q swap circuitry reduces the phase-shifting by one fourth of the original range. The wide band phase shifter is suitable for multi-standard radios, since just one phase shifter is needed to support all standards. This capability of the phase shifter could potentially reduce the size of the die and simplify the design. The measurement shows that the phase shifter is able to provide 360˚ of phase-shifting at the output base band signal when the LO is varying from 1.5GHz to 6GHz. A wider range of the phase shifter is achievable by reducing the capacitance load and increasing the number of cascaded delay cells. The proposed phase shifter is capable of achieving a very high resolution. The resolution of the phase shifter is a function of the inverter current capability and the load capacitance. The measurements show the average resolution of the proposed phase shifter is about 1.32ps. Passive components usually take up a large area on the chip. A MOS capacitor is used as the load to reduce the area of the proposed phase shifter. A method is proposed to improve the phase shifter stability over the temperature and process variations. This method is based on the fact that the propagation delay of an inverter is inversely proportional to the power supply. Therefore, the phase shifters’ power supply must be varied to maintain a relatively constant phase shifter resolution over the temperature and process variations.

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This research aims to design and implement GaAs HBT MMICs for the two crucial components in W-CDMA transmitters, quadrature modulator and upconverter, with thorough evaluation of the package and PCB effects. To construct a strong theoretical foundation, the small-signal modeling of HBTs and the EM-characterization of package and PCB interconnects are intensively studied. In this dissertation, a novel extrinsic-inductance independent approach is developed for direct extraction of the intrinsic elements in a hybrid-pi equivalent circuit of HBTs. The interconnects of leadless RFIC packages and test PCBs are investigated using the 3-D EM simulation tools and transformed into the equivalent circuits for co-analysis with the designed HBT MMICs. The first HBT MMIC design is a W-CDMA direct-conversion quadrature modulator incorporating a new 90 degrees phase shifter. Although the proposed 90 degrees phase shifter has a remarkable advantage over the others in implementation loss, it is rather susceptible to the package and PCB effects, resulting in a moderate degradation of EVM. The second HBT MMIC design is a W-CDMA upconverter incorporating a popular micromixer. Although the micromixer-based upconverter consumes much less current at low output powers to achieve the same high linearity when compared to a Gilbert mixer-based design, it is quite susceptible to the package and PCB effects, causing a significant degradation in ACPR. Comparison between theory and measurement shows good agreement in evaluating the influences of package and PCB interconnects on both HBT MMICs.

Recent developments in the area of microfabrication technologies, has enabled the fabrication of many radio frequency/microwave components with better performance and lower cost than possible with semiconductor based fabrication technology. Many of these microfabricated RF components such as switches and phase shifters, popularly known as RF MEMS, are aimed at reducing the insertion loss and improving other performance parameters such as linearity. For these devices size miniaturization is not necessarily important, as in practical subsystems, these components are integrated with RF front-ends on a laminate. This thesis deals with concepts of a low cost passive phase shifter fabricated in-situ on a microwave laminate. The operation of this Mesoscale Electrostatically actuated Phase shifter on microwave Laminate (MEPL) is similar to that of a micromachined distributed MEMS transmission line (DMTL) phase shifter. In spite of advantages of low losses, wide bandwidth, low DC power consumption and high linearity over semiconductor/MMIC technology, microfabricated phase shifters are often not used in field because of issues related to fabrication reliability, packaging and integration. On the other hand, the proposed MEPL will have all the advantages of conventional MEMS phase shifters with additional benefit of lower cost. Furthermore, these are integrable to form a monolithic phased array. A MEPL phase shifter of 50-bridges periodically distributed on the co-planar waveguide (CPW) transmission line is demonstrated in this thesis. MEMS air bridges are electrostatically actuated to vary the capacitance of the transmission line, which changes the phase velocity of the propagation RF signal, consequently phase at the output port. The realized MEPL is characterized for electromagnetic as well as electromechanical performance. The electromechanical characterization of this device is performed using a Laser Doppler Vibrometer (LDV). The measured data showed good agreement with the analytical data.. Major application of a phase shifter is in a phased array antenna system. MEPL is particularly suited for a monolithic phase array antenna. The proposed monolithic phased array antenna system fabrication approach utilizes extremely simple and economical modern printed circuit board technology to pattern the conventional microwave laminate and copper foil. A complete monolithic phased array antenna system is fabricated on a microwave laminate using an embedded phase shifter operating with electrostatic principles. Other components such as DC block and bias tee are integrated into the CPW-microstrip transitions to optimize the space and performance. Integrated phased array antenna is fabricated and tested to demonstrate the beam steering capability. Measured S11 is better than -15dB at the operating frequency of 9.8GHz. The beam steering capability is shown as proof of concept by showing the beam scan angle of 10deg with bias voltage of 125V. The mesoscale phase shifter demonstrated in this thesis has several advantages compared to micromachined phase shifters. The proposed fabrication approach does not use metal deposition/patterning process, which removes the need of high cost clean room and sophisticated films deposition equipments. Secondly, as there are no thin films used, stiction is not expected on phase shifters fabricated with this approach. Since this approach uses thicker metal films, the power handling capability is expected to be significantly higher than micromachined phase shifters. Since conventional phased array antenna system components are fabricated on a microwave laminate, micro machined phase shifters realized on semiconductor substrates are required to be packaged separately before integrating with such phased array circuits. Packaging of the micro-machined RF-MEMS/MEMS devices is still a major issue and contributes to a substantial part of the total cost. Unlike micromachined phase shifters which are required to be packaged and then embedded in phased array applications, device presented in this thesis is packaged in-situ. Compared to similar monolithic phased array antenna reported on silicon substrate which are limited by wafer size, these arrays can be easily extended for larger arrays on microwave laminate as these are available in large size. To summarize, the proposed fabrication approach for phase shifters overcomes many limitations of micromachined components for microwave applications while retaining most of their advantages compared to other existing approaches based on ferrites or semiconductor technologies.

The analysis and design of passive broadband negative group delay (NGD) transmission line phase shifters is presented. By extending the metamaterial transmission line concept to include loss, a NGD unit cell is proposed. Phase shifters are supplemented with NGD unit cells to produce a flattened phase response significantly increasing phase bandwidths. The design methodology of a NGD phase shifter is presented with consideration of nominal phase, frequency, impedance, maximum insertion loss and bandwidth. The relation between gain, bandwidth and group delay signifies a fundamental design limitation and tradeoff. A significant application of NGD phase shifters for removing beam squint in series fed antenna arrays is discussed. Several NGD phase shifters are fabricated and experimentally verified in the UHF band upwards of 1 GHz using planar microstrip transmission lines loaded with passive surface mount RF components with both positive and negative phase shifts.

The analysis and design of passive broadband negative group delay (NGD) transmission line phase shifters is presented. By extending the metamaterial transmission line concept to include loss, a NGD unit cell is proposed. Phase shifters are supplemented with NGD unit cells to produce a flattened phase response significantly increasing phase bandwidths. The design methodology of a NGD phase shifter is presented with consideration of nominal phase, frequency, impedance, maximum insertion loss and bandwidth. The relation between gain, bandwidth and group delay signifies a fundamental design limitation and tradeoff. A significant application of NGD phase shifters for removing beam squint in series fed antenna arrays is discussed. Several NGD phase shifters are fabricated and experimentally verified in the UHF band upwards of 1 GHz using planar microstrip transmission lines loaded with passive surface mount RF components with both positive and negative phase shifts.

This master’s thesis deals with phase-shifting transformers (PST) and coordination of electrically close devices in an interconnected region. Theoretical research is performed in the work, describing methods of power control, function and design of PST, as well as actual methods of PST coordination in the rest of the world. Based on the research there is an optimalisation algorithm designed in MATLAB, which computes recommended tap petting of PST based on the network configuration. In the second part of this thesis there are described components of this algorithm and also presented the results of three demonstrative scenarios. Algorithm is able to solve minor problems in the network; more complex problems are beyond its solving ability. For an improved functionality there is a necessity to further expand this algorithm by a network redispatch solving algorithm.

Phased array antennas, capable of controlling the direction of their radiated beam, are demanded by many conventional as well as modern systems. Applications such as automotive collision avoidance radar, inter-satellite communication links and future man-portable satellite communication on move services require reconfigurable beam systems with stress on mobility and cost effectiveness. Microwave phase shifters are key components of phased antenna arrays. A phase shifter is a device that controls the phase of the signal passing through it. Among the technologies used to realize this device, traditional ferrite waveguide phase shifters offer the best performance. However, they are bulky and difficult to integrate with other system components. Recently, ferrite material has been introduced in Low Temperature Co-fired Ceramic (LTCC) multilayer packaging technology. This enables the integration of ferrite based components with other microwave circuitry in a compact, light-weight and mass producible package. Additionally, the recent concept of Substrate Integrated Waveguide (SIW) allowed realization of synthesized rectangular waveguide-like structures in planar and multilayer substrates. These SIW structures have been shown to maintain the merits of conventional rectangular waveguides such as low loss and high power handling capabilities while being planar and easily integrable with other components. Implementing SIW structures inside a multilayer ferrite LTCC package enables monolithic integration of phase shifters and phased arrays representing a true System on Package (SoP) solution. It is the objective of this thesis to pursue realizing efficient integrated phase shifters and phased arrays combining the above mentioned technologies, namely Ferrite LTCC and SIW. In this work, a novel SIW phase shifter in ferrite LTCC package is designed, fabricated and tested. The device is able to operate reciprocally as well as non-reciprocally. Demonstrating a measured maximum reciprocal phase shift of 132o and maximum non-reciprocal shift of 118o at 12 GHz. Additionally a slotted SIW antenna is designed and integrated with the phase shifter in an array format, demonstrating a beam scanning of ± 15o. The design is highly suitable for mobile automotive radars and satellite communications systems.