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Modelling of Measurement Equipment for High Frequency Electromagnetic FieldsTigga, Celine January 2015 (has links)
The aim of this thesis was to develop a model of a receiver which could be quickly used to analyze radiated interference levels from data captured at the output of the antenna equipment used to measure radiated energy. Active circuits were mainly used in developing this model for the ease with which the design and simulations could be carried out in OrCAD. The guiding document for the thesis work has been CISPR 16-1-1 (International Special Committee on Radio Interference part 16-1-1) which specifies the characteristics and performance of equipment for the measurement of radiated interference. The testing of this receiver model was carried out as far as possible based on the test setups recommended in CISPR, and all results have been compared with the standards laid down for the model. Using the results, it will be shown that a CISPR EMI receiver can be modeled as a simple EMI receiver consisting of filtering, mixing and detecting circuits built according to specifications.
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Some applications of nuclear orientationNambudripad, Narayanan January 1980 (has links)
This thesis describes Nuclear Orientation and radiofrequency magnetic susceptibility experiments on the enhanced nuclear antiferromagnet holmium vanadate (HoVO<sub>4</sub>) from 1 K down to about 1 mK and in applied fields of up to 2.4 tesla. Adiabatic demagnetisation of single crystals of HoVO<sub>4</sub> allowed a mean nuclear spin temperature of about 1 mK to be reached. R.f. magnetic susceptibility measurements at approximately 2.4 mK and in an applied field of about 1.5 x 10<sup>-2</sup> T identified the spin 'flop' phase of the nuclear anti-ferromagnet HoVO<sub>4</sub>. The Néel temperature T<sub>N</sub> was determined to be 4.0 (2) mK which is in good agreement with the value of 4.8 mK calculated for the dipole-dipole interaction of the enhanced magnetic moments at the Ho site. Gamma-ray anisotropy measurements of <sup>166m</sup>HoVO<sub>4</sub> showed that in low applied fields (B ≮ 0.5 x 10<sup>-2</sup> T) and temperatures of about 1 mK the antiferromagnetic domains were uniformly distributed in the a-a' plane of the tetragonal zircon crystal structure. This was interpreted in terms of pinning of the nuclei due to crystalline imperfections. The spin 'flop' phase was identified in an applied field of 1.2 x 10<sup>-2</sup> T which is in good agreement with the susceptibility measurements. Demagnetisation experiments down to the relatively high residual fields of 4.2 x 10</sup>-2</sup> T and 7.4 x 10</sup>-2</sup> T and temperatures of about 2 mK showed that the effective field at the nucleus was much smaller than the applied field thus indicating that there was some antiferromagnetic ordering even at these relatively high fields. The magnetic dipole moment of <sup>166m</sup>Ho was estimated to be 3.60 (6) μ<sub>N</sub> from gamma-ray anisotropy measurements of some gamma transitions of known NO parameters. This value is in good agreement with the value of 3.69μ<sub>N</sub> calculated for the Nilsson configuration [6337./2]<sub>n</sub> [5237/2]<sub>p</sub> for the extra-core neutron and proton respectively. Mixing ratio (δ) measurements for gamma-ray transitions between the (K<sup>π</sup> = 2<sup>+</sup>) γ-vibrational and (K<sup>π</sup> = 0<sup>+</sup>) ground state rotational bands of the daughter nucleus <sup>166</sup>Er showed that Ml transition probabilities are predominantly via ΔK = 1 band mixing which is in good agreement with systematics for deformed nuclei in this mass region. Nuclear refrigeration experiments on a powdered compressed HoVO<sub>4</sub> - copper pill allowed a lattice temperature of 3.9 (3) mK to be reached. Thermal contact measurements on a similar pill showed that the effective area of contact between the salt particles and copper was only about 30 cm<sup>2</sup> which was a small fraction of the total surface area available. Preliminary work on a HoVO<sub>4</sub> - gold pill enabled a <sup>60</sup>Co ̲C̲o thermometer to be cooled to 6.0 (l) mK.
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Wideband HF power amplifier modelling for linearisationUrmonas, Richard January 2003 (has links)
Existing linearisation methods were examined to establish the requirements for a wideband power amplifier model. A range of memoryless models were investigated, in particular polynomial models. No suitable memoryless models were found. The shortcomings of the models were analysed and directions for future investigations presented. / Thesis (MEng(ElectronicsEngineering))--University of South Australia, 2003
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Wideband HF power amplifier modelling for linearisationUrmonas, Richard January 2003 (has links)
Existing linearisation methods were examined to establish the requirements for a wideband power amplifier model. A range of memoryless models were investigated, in particular polynomial models. No suitable memoryless models were found. The shortcomings of the models were analysed and directions for future investigations presented. / thesis (MEng(ElectronicsEngineering))--University of South Australia, 2003.
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Wideband HF power amplifier modelling for linearisationUrmonas, Richard January 2003 (has links)
Existing linearisation methods were examined to establish the requirements for a wideband power amplifier model. A range of memoryless models were investigated, in particular polynomial models. No suitable memoryless models were found. The shortcomings of the models were analysed and directions for future investigations presented. / Thesis (MEng(ElectronicsEngineering))--University of South Australia, 2003
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Design techniques for first pass silicon in SOC radio transceiversWilson, James Edward, January 2007 (has links)
Thesis (Ph. D.)--Ohio State University, 2007. / Full text release at OhioLINK's ETD Center delayed at author's request
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Cognitive radios spectrum sensing issues /Kataria, Amit, January 2007 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2007. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on March 28, 2008) Includes bibliographical references.
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Steady-state methods for simulation of RF and microwave circuits /Kleiner, Madeline. January 1900 (has links)
Thesis (Ph.D.)--Tufts University, 2002. / Adviser: Mohammed Afsar. Submitted to the Dept. of Electrical Engineering. Includes bibliographical references (leaves 121-128). Access restricted to members of the Tufts University community. Also available via the World Wide Web;
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An RFID-based track-and-trace anti-counterfeiting systemPoon, Chun-hin. January 2007 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2008. / Also available in print.
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RF linearity analysis in nano scale CMOS using harmonic balance device simulationsKopalle, Deepika, Niu, Guofu. January 2005 (has links) (PDF)
Thesis(M.S.)--Auburn University, 2005. / Abstract. Vita. Includes bibliographic references.
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