ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada / Reconfigurable patch antenna integrated with RF mircoelectromechanical system (MEMS) switches is presented in this paper. The proposed antenna radiates circularly polarized wave at selectable dual frequencies (4.7 GHz and 7.5GHz) of high frequency ratio (1.6:1). The switches are incorporated into the diagonally-fed square patch for controlling the operation frequency, and a rectangular stub attached to the edge of the patch acts as the perturbation to produce the circular polarization. Gain of proposed antenna is 5 - 6dBi, and axial ratio satisfies 3dB criterion at both operating frequencies. The switches are monolithically integrated on quartz substrate. The antenna can be used in applications requiring frequency diversity of remarkable high frequency ratio.

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In this thesis, three radio frequency integrated circuits (RFICs) were digitally assisted for varying signal power, frequency or both. Performance paramters were 'optimized' in the sense of obtaining the best performance improvement possible through the methods used. The digital assist method used a lookup table (LUT) of optimal bias points measured through extensive sweeps and linear interpolation to determine the optimal bias point of the chip between measured points. A Gilbert Cell was fabricated in 0.13 μm CMOS. Transistor gate bias voltages were swept with input power to find the optimal bias voltages for intermodulation distortion (IMD) performance. A power detector was on-chip for the digital assist. Linear interpolation was used to optimize biases for any input power between initially measured points. Whereas distortion generally increases with input power, the digitally assisted device reduced the distortion of large signals. The IIP3 was 2.83 dBm from -3.11 dBm, and the P1dB was -3.33 dBm from -12.06 dBm. The RF bandwidth was measured as 1 to 12 GHz and DC power consumption varied from 2.06 to 3.27 mW. A noise cancelling low noise amplifier (LNA) was designed and fabricated in 0.13 μm CMOS. A feedback capacitor was used to boost the gain of the input transistor for lower DC power and better S11. An on-chip frequency detector was implemented for the digital assist. The gain rolled off gradually from 1 GHz until the 3 dB cutoff at 7 GHz. The average noise figure was 4.1 dB and less than 5 dB across the band. With digital assist, the gain curve was flattened at about 15 dB with to a broader 8 GHz bandwidth without negatively affecting the noise figure. The S11 was below -12 dB. A power amplifier (PA) previously designed in 0.8 μm Gallium Nitride (GaN) used third order IMD cancellation by derivative superposition effective at a fixed frequency and output power. Digital assist eliminated the extreme sensitivity to variations. Digital assist and bilinear interpolation maintained a 10 dB improvement in OIP3 over the entire 1 to 6 GHz band for varying output power between 21 and 24 dBm. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2013-07-30 12:02:50.668

This thesis describes the development of a novel game-like method, the AnimalSeek method, which can be used, along with motion tracking technology, to measure localisation ability of a child under five years of age. For the game-like task to be successful, a high number of responses (in particular correct head turn responses) was required. Previous studies, although not all looking at localisation ability, have used many different techniques to obtain the maximum number of responses from a child. The children were engaged inside a custom-built environment inside an anechoic chamber. Three large video screens onto which backgrounds and animated characters were projected and manipulated and used to engage the child in the game-like task. Behind the video screens were loudspeakers from which the auditory stimulus where presented. A correct response to the auditory stimulus i.e. a head, hand or eye movement towards the target speaker was rewarded with a animated character presented on the screens (incorrect responses were presented with a static character). The location of the reward in relation to the auditory stimulus was a point of interest and was investigated to see how it affected the number of responses. The method shows it was possible to engage the child with the visual environment and obtain responses, however, the results showed generally fewer head turn responses than expected, especially in the younger age groups. Motion tracking technology was used to measure the localisation ability of the children, as well as measuring the responses, the motion tracking data was used and programs developed which could automatically classify the responses the children made to the sounds. The thesis has shown that it is possible to devise a new method which can be used to engage the child in the task and extract and classify their responses to auditory stimuli in order to measure their localisation ability.

The Coastal Batholith of central Chile preserves structures that record the concentration, migration, transportation, and emplacement of magma during the progressive construction of a sheeted dike complex. This sheeted dike complex is divided into three main structural-geographic domains. The northwestern domain contains an abundance of deformed microgranitoid enclaves that host features that facilitated the concentration of melt during crystallization. The formation of interconnected dilational sites produced an array of lecocratic zones that may have formed larger dike networks that facilitated the transportation of melt-rich magma producing new magmatic units of similar mineralogy. The central domain is characterized by the presence of two tonalitic units that contain enclave swarms distinguished by their general packing arrangement and degree of elongation. Di erences in the fabric architecture of these enclave swarms are displayed by two separate three-dimensional fabric analyses using the Rf/ method, which indicates an abrupt transition from low-distortion oblate fabrics to more distorted prolate geometries. These changes are compared to the statistical alignment of feldspar phenocrysts that indicate general attening in both units with a higher degree of alignment within the XZ fabric plane for the younger tonalite. The third (southeastern) domain is distinguished by meter-scale, compositionally and texturally diverse sheeted dikes intercalated with biotite-rich migmatite screens of the host gneiss along the pluton margin. The need to process large quantities of fabric data from central Chile presented the opportunity to establish a comprehensive method for the quanti cation of three-dimensional rock fabrics following the Rf/ and Fry methods. In order to test the utility of this procedure, a three-dimensional synthetic model of known strain shape, magnitude, and orientation was processed. The results of this assessment indicate that the procedure accurately calculated the expected state of strain within a small margin of error. Finally, a natural example is presented to test the method's ability to quantify the fabrics of deformed rocks. This example is a \lineation much greater than foliation" (L>>S) metagranite augen gneiss from the Coastal Batholith of central Chile. This analysis resulted in calculated fabric ellipsoids from both the Rf/ and Fry methods that clearly display signi cantly prolate geometries at moderate distortions. The development of the three-dimensional rock fabric quanti cation procedure highlighted the need to teach analytical strain techniques in three-dimensions. To allow for this application, an interactive R script (FRY3D) was created speci cally to aid in the instruction and visualization of three-dimensional strain calculation at the advanced undergraduate and graduate levels. This tutorial was presented to a structural geology course of 20 students at the undergraduate level with a two part semi-quantitative concept assessment before and after the presentation. The results of this assessment indicate a positive increase in student's understanding of three-dimensional nite strain. Finally, a simple examination of analytical error associated with the Panozzo projection technique for strain analysis is presented and indicates relationships among population size, strain magnitude, and initial fabric. My results suggest that this method is most robust when applied to sections containing greater than approximately 125 lines. Moreover, the magnitude-dependent error indicates that the method may be better suited for rocks deformed at low to moderate strains. I recommend an adaption to the initial conditional assumptions for this method that lines exhibit an initial radial symmetry when recentered to a common point.

Doctor of Philosophy / Department of Electrical and Computer Engineering / William B. Kuhn / Design challenges and solution methods for Watt-level UHF CMOS power amplifiers are presented. Using the methods, a fully-integrated UHF (400MHz) CMOS power amplifier (PA) with more than 1-Watt output is demonstrated for the first time in Silicon on Sapphire (SOS) process. The design techniques are extended for a two-stage five-chip 5-Watt CMOS PA. In the 1-Watt PA, a differential stacked PMOS structure with floating-bias and a 1:3 turns-ratio output transformer are chosen to overcome low breakdown voltage (Vbk) of CMOS and chip area consumption issues at UHF frequencies. The high Q on-chip transformer on sapphire substrate enables the differential PA to drive a single-ended antenna effectively at 400 MHz. The PA is designed for a surface-to-orbit proximity link microtransceiver, used on Mars exploration rovers, aerobots and small networked landers. In a standard package the PA delivers 30 dBm output with 27 % PAE. No performance degradation was observed in continuous wave (CW) operation with various output terminations and the PA was tested to 136 % of its nominal 3.3 V supply without failure. Stability analysis and measurements show that the PA is stable in normal operation. It is also shown that the PA is thermally reliable. In the microtransceiver circuits, the PA works in conjunction with transmit/receive (TR) switch to allow nearly the full 1-Watt to reach the antenna. The 1-Watt PA design is also leveraged to demonstrate a power-combined two-stage five-chip PA. The 1-Watt PA’s output balun is modified for the four-transformer combining. Four identical chips are wire-bonded in the output stage and the fifth identical chip is added as a drive-amplifier. Despite low efficiency due to damaged bias circuits, the PA provides 5-Watt output power (37 dBm) at 480 MHz with 17 % PAE with 17 dB gain. The PA layout is carried out considering full integration on a 7×10mm2 die. It will be the highest output CMOS PA ever reported once the full integration is implemented. The research contributes to state of the art by developing design-techniques for a TR switch and PAs on SOS process. The resonant TR switch technique is applied to a full transceiver and the multi turns-ratio on-chip transformer is used in PA’s output matching network for the first time. The PA design is also extended to the 5-Watt PA, demonstrating the highest output power in CMOS process.

Chalcogenide phase change (PC) materials can be reversibly transformed between the high resistivity (~ 1 Ω∙m) amorphous state (OFF-state) and low resistivity (~ 10-6 Ω∙m) crystalline state (ON-state) thermally, both are stable at the room temperature. This makes them well suited as reconfigurable RF switches and non-volatile memories. This work will present the understandings of two key characteristics of PC materials, the crystallization dynamics and the threshold voltage (Vth), as they determine performance limitations in these applications. Crystallization dynamics describe the correlations of the states, temperature and time; the Vth is the trigger of the threshold switching which leads to the “break down” of PC materials from OFF-state to ON-state. The four-terminal indirectly-heated RF switches with high cut-off frequency (> 5 THz) has advantages over other technologies but its programming power (~ 1.5 W) is yet to be reduced. Measuring the maximum allowed RESET quench time in the crystallization dynamics is critical for designing low power switches. As a major contribution, this work provides a universal methodology for accurate heater thermometry and in-situ crystallization measurements for this study. On the other hand, understanding the Vth is essential for high power handling applications as it determines the maximum power that an OFF-state switch can withstand without being spontaneously turned on. This work will discuss new observations and learnings from Vth measurements including the geometry dependent Vth variations which provide insights into the threshold switching mechanism. Unlike RF switches, faster crystallization is desired for memories to improve the write speed. The non-Arrhenius crystallization needs to be explored to achieve short crystallization time (< 10 ns) at high temperature (> 700 K). As another major contribution, this work will present a nano-scale (~ 100 nm) high-speed (thermal time constant < 5 ns) PC device for assessing the crystallization time in this regime, and provide a comprehensive learning for the crystallization dynamics from 300 K to 1000 K by developing a unified framework based on the fragility model and growth-dominated crystallization. This can be used to accurately simulate the crystallization process for any device geometry and estimate the RF switches power and Vth.

During the thesis, a two-staged analog baseband circuit incorporating a passive analog filter and a wideband voltage amplifier were successfully designed, implemented in an IC mask layout in a 65nm CMOS technology, and joined with a previously designed analog front-end design to form a wideband observation receiver. The baseband circuit is capable of receiving an IF bandwidth up to 990MHz produced by the analog front-end using low-side injection. The final circuit shows high IMD3 of at least 90 dBc. The voltage amplifier delivers a voltage amplification of 15 dB with around 0.08 dB amplitude precision over the bandwidth, while the passive filter is capable of a passband amplitude precision of 0.67 dB over the bandwidth, while effectively suppress signal images created by the mixer with at least 60 dBc. Both stages were realized in an IC mask layout, in addition, the filter layout were simulated using an EM simulator.

Klimatologisch signifikante räumliche Strukturen der Niederschlagsverteilung in der Stadt Berlin und des Umlandes in Brandenburg wurden für den Zeitraum 1951-2000 untersucht, die durch Wirkung des urbanen Raumes verursacht werden. Für die Analyse werden Primärdaten von 247 Niederschlagsmessstationen verwendet, woraus Gebietsmittelwerte für 636 administrative Teilflächen sowie für 12 Teilflächen eines zur mittleren Windrichtung des Niederschlagstages parallelen Analyse-Transekts für jeden der 11848 Niederschlagstage interpoliert werden. Für 17 ausgewählte Kombinationen von acht Atmosphärenparametern wurde der Niederschlagsdatensatz zu klassifizierten Teilmengen gruppiert und als eigenständige geostatistische Experimente ausgewertet. Die Spannweite der in den einzelnen Experimenten verglichenen Gebietsmittelwerte überschreitet in der Regel 10 Prozent der mittleren Niederschlagshöhen nicht. Der dominierende Faktor für die Herausbildung unterscheidbarer räumlicher Niederschlagsverteilungen im Untersuchungsgebiet ist die Windrichtung in der unteren Troposphäre. Während sich der Stadtkörper unter Bedingungen, die kleinräumige Niederschlagsentstehung begünstigen, im Mittel lokal verstärkend auswirkt, kommt es bei großräumig gesteuerter Niederschlagsentstehung über dem Stadtgebiet zu einer Verringerung der Tagessummen des fallenden Niederschlags. Die Experimente angewendet auf den Datensatz weisen darauf hin, dass die urbane Verstärkung durch intensivierte Niederschlagsbildung über der Stadt bedingt wird, während die urbane Verminderung aus der Veränderung des Niederschlagsgeschehens innerhalb der Stadtatmosphäre resultiert. / An analysis of the climatologically significant spatial structures resulting from urban modification of the precipitation distribution was carried out at the sample site Berlin and its surrounding areas in Brandenburg for a period from 1951 to 2000. For the 11848 precipitation days the daily sums of 247 measurement sites are interpolated into mean areal precipitation for 636 administrative sub regions as well as for 12 elements of transects placed parallel to the mean daily wind direction. 17 combinations of eight atmospheric parameters were used to group the precipitation data into classified subsets. These subsets are treated as data resulting from independent geostatistic experiment configurations. The mean range of interpolated precipitations does not exceed 10 percent of the respective mean precipitation height in the particular experiments. The dominant synoptic factor causing the evidence of distinguishable spatial precipitation structures appears to be the wind direction in the lower troposphere. At weather conditions inducing local precipitation genesis the urban body induces predominantly locally intensified precipitation heights. When precipitation is formed mainly by synoptic processes the daily precipitation is being reduced over the city region. The experiment layouts related to these observations indicate that urban precipitation amplification evolves from intensified generation processes while urban reduction results from modified conditions for precipitation falling through the urban atmosphere.