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Turbo-equalization for QAM constellations /Petit, Paul F. Unknown Date (has links)
While the focus of this work is on turbo equalization, there is also an examination of equalization techniques including MMSE linear and DFE equalizers and Precoding. The losses and capacity associated with the ISI channel are also examined . Iterative decoding of concatenated codes is briefly reviewed and the MAP algorithm is explained. / Thesis (PhDTelecommunications)--University of South Australia, 2002.
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Psychophysical explorations of the illusion underpinning frequency doubling perimetry in glaucomaVallam, Kunjam Unknown Date (has links) (PDF)
The spatial frequency doubling illusion (FDI) occurs when the contrast of a low spatial frequency sinusoidal grating is modulated at high temporal frequencies – its apparent spatial frequency increases. Earlier suggestions were that the FDI is generated by a specific class of retinal ganglion cells, which are preferentially lost in the early stages of glaucoma. Based on this linking theory, frequency doubling perimetry (FDP) was developed and several clinical reports confirmed its high efficiency in diagnosing early glaucomatous vision loss. However, this linking theory is not universally accepted and newer suggestions posit that the illusion arises because of temporal frequency related difficulties in temporal phase encoding ability. This thesis psychophysically examines the spatiotemporal characteristics of both the FDI and temporal phase encoding ability with achromatic and equi-luminant (both red-green (RG) and blue-yellow (BY)) gratings at a range of spatiotemporal parameters including those eliciting the FDI. (For complete abstract open document)
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High-performance RFID systems.Jamali, Behnam January 2006 (has links)
Title page, abstract and table of contents only. The complete thesis in print form is available from the University of Adelaide Library. / In this thesis, I present and analyze two of the most fundamental constraints of Radio Frequency Identification Systems (RFID), power rectification and signaling. These two issues play an important role in the continuing development of RFID systems. A passive RFID tag draws power from the RF field created by an RFID reader and uses it to energize its circuitry. It does this by rectification of the reader's radiated RF field using rectifying circuitry. The power then available to the tag is dependent upon both the available field strength and the efficiency of the rectification process. One option for increasing the operating range of an RFID system without increasing the reader's field strength is to increase the efficiency of the tag's rectification structure. A major component of any rectification circuit is a diode type device and so, the first part of the thesis focuses on the design and implementation of a novel high efficiency Schottky Barrier Diode (SBD) on a standard CMOS process. The forward voltage drop of the SBD diode was investigated and analytic equations formulated considering the Schottky barrier drift region resistance and the contributions from the p⁺ guard-grid. A design procedure to minimize the drift region resistance for any blocking voltage was derived. The fundamental trade-off between the forward voltage and leakage current in the novel SBD concept was determined. Based on the critical review of the Schottky diodes fabricated in the first part, new structures of novel SBD were designed to address most of the open issues related to its reverse break-down voltage and series resistance. Detailed analysis of the important design parameters of the novel Schottky barrier diode were performed using HSPICE with the parameter set used in the calibration process. The novel structure was also compared to an alternative fabrication approach, specifically, a NMOS and PMOS gate-cross-connected bridge. The comparison shows that the novel structure provides a 10% higher figure of merit for power rectification. In the later part of the thesis, an analysis of circuit advantages enabled by the novel SBD is given. The circuit simulation showed that by utilizing the novel SBD the operating frequency of the circuit can be increased to the UHF region while maintaining approximately the same power efficiency as that achievable when using a discrete Schottky diode. This leads to the possibility of dramatic improvements in size, weight and cost of the RFID transponder circuits. Signaling also plays an important role in the development of RFID systems. The choice of signaling methods and protocols determines not only the spectrum bandwidth usage, but also the data throughput. Also with constantly changing standards and regulations, it is important to be able to characterize and optimize these issues. Therefore the second part of this dissertation presents the design, implementation and evaluation of a novel RFID data logging reader architecture based on software radio concepts. The system is designed to overcome the many challenges and exploit the advantages of performing real-time signal processing and data logging in an RFID environment. The proposed concept has a unique multi-band RFID tag reader platform and has been designed to read tags conforming to the Electronic Product Code (EPC ) specifications in both the HF and UHF frequency bands. The hardware architecture consists of a general purpose analogue front end up/down-converter for each band, followed by a software radio based architecture allowing easy adaptation to new frequencies and protocols if required. The last chapter presents the results of investigations conducted to determine the ability of the proposed reader architecture to communicate with tags in typical channel noise and environmental conditions present in an RFID operational environment. Studies of the effects of reader interference in multi-reader environments and the development of an anti-collision protocol signaling to address and mitigate those effects are also presented. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1222149 / Thesis (Ph.D.) -- University of Adelaide, School of Electrical and Electronic Engineering, 2006
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High-performance RFID systems.Jamali, Behnam January 2006 (has links)
Title page, abstract and table of contents only. The complete thesis in print form is available from the University of Adelaide Library. / In this thesis, I present and analyze two of the most fundamental constraints of Radio Frequency Identification Systems (RFID), power rectification and signaling. These two issues play an important role in the continuing development of RFID systems. A passive RFID tag draws power from the RF field created by an RFID reader and uses it to energize its circuitry. It does this by rectification of the reader's radiated RF field using rectifying circuitry. The power then available to the tag is dependent upon both the available field strength and the efficiency of the rectification process. One option for increasing the operating range of an RFID system without increasing the reader's field strength is to increase the efficiency of the tag's rectification structure. A major component of any rectification circuit is a diode type device and so, the first part of the thesis focuses on the design and implementation of a novel high efficiency Schottky Barrier Diode (SBD) on a standard CMOS process. The forward voltage drop of the SBD diode was investigated and analytic equations formulated considering the Schottky barrier drift region resistance and the contributions from the p⁺ guard-grid. A design procedure to minimize the drift region resistance for any blocking voltage was derived. The fundamental trade-off between the forward voltage and leakage current in the novel SBD concept was determined. Based on the critical review of the Schottky diodes fabricated in the first part, new structures of novel SBD were designed to address most of the open issues related to its reverse break-down voltage and series resistance. Detailed analysis of the important design parameters of the novel Schottky barrier diode were performed using HSPICE with the parameter set used in the calibration process. The novel structure was also compared to an alternative fabrication approach, specifically, a NMOS and PMOS gate-cross-connected bridge. The comparison shows that the novel structure provides a 10% higher figure of merit for power rectification. In the later part of the thesis, an analysis of circuit advantages enabled by the novel SBD is given. The circuit simulation showed that by utilizing the novel SBD the operating frequency of the circuit can be increased to the UHF region while maintaining approximately the same power efficiency as that achievable when using a discrete Schottky diode. This leads to the possibility of dramatic improvements in size, weight and cost of the RFID transponder circuits. Signaling also plays an important role in the development of RFID systems. The choice of signaling methods and protocols determines not only the spectrum bandwidth usage, but also the data throughput. Also with constantly changing standards and regulations, it is important to be able to characterize and optimize these issues. Therefore the second part of this dissertation presents the design, implementation and evaluation of a novel RFID data logging reader architecture based on software radio concepts. The system is designed to overcome the many challenges and exploit the advantages of performing real-time signal processing and data logging in an RFID environment. The proposed concept has a unique multi-band RFID tag reader platform and has been designed to read tags conforming to the Electronic Product Code (EPC ) specifications in both the HF and UHF frequency bands. The hardware architecture consists of a general purpose analogue front end up/down-converter for each band, followed by a software radio based architecture allowing easy adaptation to new frequencies and protocols if required. The last chapter presents the results of investigations conducted to determine the ability of the proposed reader architecture to communicate with tags in typical channel noise and environmental conditions present in an RFID operational environment. Studies of the effects of reader interference in multi-reader environments and the development of an anti-collision protocol signaling to address and mitigate those effects are also presented. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1222149 / Thesis (Ph.D.) -- University of Adelaide, School of Electrical and Electronic Engineering, 2006
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A study of the effects of linear networks on FM waves /Johnson, Preston Benton, January 1966 (has links)
Thesis (Ph. D.)--Virginia Polytechnic Institute, 1966. / Vita. Abstract. Includes bibliographical references (leaves 113-116). Also available via the Internet.
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Frequency tracking and its application in speech analysisTotarong, Pian. January 1983 (has links)
Thesis (M.S.)--Ohio University, August, 1983. / Title from PDF t.p.
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Nonlinearities and regime shifts in financial time series /Åsbrink, Stefan E., January 1900 (has links)
Diss. Stockholm : Handelshögsk.
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A new non-linear GARCH model /Hagerud, Gustaf E., January 1900 (has links)
Diss. Stockholm : Handelshögsk.
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Quasi-optimum receivers for analog FM signals over Rayleigh fading channels.Le, Nguyen Huu. January 1977 (has links) (PDF)
Thesis (Ph.D. 1979) from the Department of Electrical Engineering, University of Adelaide.
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The design of an electronic music synthesizer.Bolton, Alan Graham. January 1977 (has links) (PDF)
Thesis (M. App. Sc. 1978) from the Department of Electrical Engineering, University of Adelaide.
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