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EXPERIMENTAL INVESTIGATION TO INFORM OPTIMAL CONFIGURATIONS FOR DYNAMIC NEAR-FIELD PASSIVE UHF RFID SYSTEMSProffitt, Donnie E., II 01 January 2013 (has links)
RFID has been characterized as a “disruptive technology” that has the potential to revolutionize numerous key sectors. A key advantage of passive RFID applications is the ability to wirelessly transmit automatic identification and related information using very little power. This paper presents an experimental investigation to inform the optimal configuration for programming passive ultra-high frequency (UHF) RFID media in dynamic applications. Dynamic programming solutions must be designed around the tag’s functionality, the physical programming configuration and environment. In this investigation, we present a methodology to determine an optimal configuration to maximize the systems programming efficiency for dynamic applications.
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Microwave-energy harvesting at 5.8 GHz for passive devicesValenta, Christopher Ryan 27 August 2014 (has links)
The wireless transfer of power is the enabling technology for realizing a true internet-of-things. Broad sensor networks capable of monitoring environmental pollutants, health-related biological data, and building utility usage are just a small fraction of the myriad of applications which are part of an ever evolving ubiquitous lifestyle. Realizing these systems requires a means of powering their electronics sans batteries. Removing the batteries from the billions or trillions of these envisioned devices not only reduces their size and lowers their cost, but also avoids an ecological catastrophe.
Increasing the efficiency of microwave-to-DC power conversion in energy-harvesting circuits extends the range and reliability of passive sensor networks. Multi-frequency waveforms are one technique that assists in overcoming the energy-harvesting circuit diode voltage threshold which limit the energy-conversion efficiency at low RF input powers typically encountered by sensors at the fringe of their coverage area.
This thesis discusses a systematic optimization approach to the design of energy-conversion circuits along with multi-frequency waveform excitation. Using this methodology, a low-power 5.8 GHz rectenna showed an output power improvement of over 20 dB at -20 dBm input power using a 3-POW (power-optimized waveform) compared to continuous waveforms (CW). The resultant efficiency is the highest reported efficiency for low-power 5.8 GHz energy harvesters. Additionally, new theoretical models help to predict the maximum possible range of the next generation of passive electronics based upon trends in the semiconductor industry. These models predict improvements in diode turn-on power of over 20 dB using modern Schottky diodes. This improvement in turn-on power includes an improvement in output power of hundreds of dB when compared to CW.
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Emittance minimization at the ELBE superconducting electron gunMöller, K., Arnold, A., Lu, P., Murcek, P., Teichert, J., Vennekate, H., Xiang, R. 26 June 2014 (has links) (PDF)
The transverse emittance is one of the most important quantities which characterize the quality of an electron source. For high quality experiments low beam emittance is required. By means of theoretical considerations and simulation calculations we have studied how the emittance of the Rossendorf superconducting radio-frequency photoelectron source (SRF gun) can be minimized. It turned out that neither a solenoid magnet nor the effect of space charge forces is needed to create a pronounced emittance minimum. The minimum appears by just adjusting the starting phase of the electron bunch with respect to the RF phase of the gun in a suitable way. Investigation of various correlations between the properties of the beam particles led to an explanation on how the minimum comes about. It is shown that the basic mechanism of minimization is the fact that the longitudinal properties of the particles (energy) are strongly influenced by the starting phase. Due to the coupling of the longitudinal and transverse degrees of freedom by the relativistic equation of motion the transverse degrees of freedom and thereby the emittance can be strongly influenced by the starting phase as well. The results obtained in this study will be applied to minimize the emittance in the commissioning phase of the SRF gun.
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Low noise RF CMOS receiver integrated circuitsWoo, Sang Hyun 09 February 2012 (has links)
The objective of this research is to design and implement low-noise wideband RFIC components with CMOS technology for the direct-conversion architecture. This research proposes noise reduction techniques to improve the thermal noise and flicker noise contribution of a low noise amplifier (LNA) and a mixer. Of these techniques, the LNA is found to reduce noise, boost gain, and consume a relatively low amount of power without sacrificing the wideband and linearity advantages of a conventional common gate (CG) topology. The research concludes by investigating the proposed mixer topology, which senses and compensates local oscillator (LO) phase mismatches, the dominant cause of flicker noise.
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Evaluation of on-line cell viability and L-lactate measurements in soft sensor for mammalian cell culturesReissig, Alexander January 2014 (has links)
Increasing demand on more effective cell culture reactors has driven optimization works to increase output of products. This has led to development of soft sensors that uses mathematical formulas to increase the available information for the parameters during runs. In the project two parameters was evaluated for use in such a soft sensor, viability by measuring on-line capacitance with Aber probe and L-lactate production using BioSenz apparatus. To determine how well these could be used both were used on batch reactors measuring on a mouse-mouse B cell hybridoma culture which produced IgG1. On-line measurements were performed by probes which measured directly on the cell suspension or withdrew sterile sample from the reactor. Measuring viability gave results with low error, which can be concluded to the variation in reference cell count, but it could not be determined if measuring L-lactate production with BioSenz works in reactors of this size. More work needs to be done on other types of reactors, like fed-batch or perfusion, or lower working volumes.
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Conductive inkjet printed antennas on flexible low-cost paper-based substrates for RFID and WSN applicationsRida, Amin H. 31 March 2009 (has links)
This thesis investigates inkjet-printed flexible antennas fabricated on paper substrates as a system-level solution for ultra-low-cost and mass production of RF structures. These modules are designed for the UHF Radio Frequency Identification (RFID) Tags and Wireless Sensor Nodes (WSN); however the approach could be easily extended to other microwave and wireless applications.
Chapter 1 serves as an introduction to RFID technology and its capabilities while listing the major challenges that could potentially hinder RFID practical implementation.
Chapter 2 discusses the benefits of using paper as a substrate for high-frequency applications, reporting its very good electrical/dielectric performance up to at least 1 GHz. The dielectric properties are studied by using the microstrip ring resonator. Brief discussion on Liquid Crystal Polymer (LCP) is also given in this chapter.
Chapter 3 gives details about the inkjet printing technology, including the characterization of the conductive ink, which consists of nano-silver-particles, while highlighting the importance of this technology as a fast and simple fabrication technique especially on flexible organic (e.g.LCP) or paper-based substrates.
Chapter 4 focuses on antenna designs. Four examples are given to provide: i) matching techniques to complex IC impedance, ii) proof of concept of inkjet printing on paper substrate through measurement results, iii) demonstration of a fully-integrated wireless sensor modules on paper and show a 2D sensor integration with an RFID tag module on paper.
Chapter 5 concludes the thesis by explaining the importance of this work in creating a first step towards an environmentally friendly generation of "green" RF electronics and modules.
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Distortion analysis of CMOS analog integrated circuits operating in the moderate inversion region and implications for RF applications /Toole, William January 1900 (has links)
Thesis (Ph. D.)--Carleton University, 2004. / Includes bibliographical references (p. 217-223). Also available in electronic format on the Internet.
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Using oscillator gain and injection-locking to measure on-chip inductor cupling /Popplewell, Peter Harris Robert, January 1900 (has links)
Thesis (M. App. Sc.)--Carleton University, 2004. / Includes bibliographical references (p. 110-113). Also available in electronic format on the Internet.
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Sensitivity analysis of nonlinear RF circuits using projection based techniques /Pai, Praveen Basty, January 1900 (has links)
Thesis (M. App. Sc.)--Carleton University, 2004. / Includes bibliographical references (p. 112-118). Also available in electronic format on the Internet.
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Automated time domain modeling of linear and nonlinear microwave circuits using recurrent neural networks /Sharma, Hitaish. January 1900 (has links)
Thesis (M.App.Sc.) - Carleton University, 2005. / Includes bibliographical references (p. 79-86). Also available in electronic format on the Internet.
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