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Wireless Power Transfer: Efficiency, Far Field, Directivity, and Phased Array AntennasFinnell, Abigail Jubilee Kragt 08 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / This thesis is an examination of one of the main technologies to be developed on the path to Space Solar Power (SSP): Wireless Power Transfer (WPT), specifically power beaming.
While SSP has been the main motivation for this body of work, other applications of power beaming include ground-to-ground energy transfer, ground to low-flying satellite wireless power transfer, mother-daughter satellite configurations, and even ground-to-car or ground-to-flying-car power transfer.
More broadly, Wireless Power Transfer falls under the category of radio and microwave signals; with that in mind, some of the topics contained within can even be applied to 5G or other RF applications.
The main components of WPT are signal transmission, propagation, and reception.
This thesis focuses on the transmission and propagation of wireless power signals, including beamforming with Phased Array Antennas (PAAs) and evaluations of transmission and propagation efficiency.
Signals used to transmit power long distances must be extremely directive in order to deliver the power at an acceptable efficiency and to prevent excess power from interfering with other RF technology.
Phased array antennas offer one method of increasing the directivity of a transmitted beam through off-axis cancellation from the multi-antenna source.
Besides beamforming, another focus of this work is on the equations used to describe the efficiency and far field distance of transmitting antennas.
Most previously used equations, including the Friis equation and the Goubau equation, are formed by examining singleton antennas, and do not account for the unique properties of antenna arrays.
Updated equations and evaluation methods are presented both for the far field and the efficiency of phased array antennas.
Experimental results corroborate the far field model and efficiency equation presented, and the implications of these results regarding space solar power and other applications are discussed.
The results of this thesis are important to the applications of WPT previously mentioned, and can also be used as a starting point for further WPT and SSP research, especially when looking at the foundations of PAA technology.
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Power Beaming and Receiving Systems for Microwave Power Transmission to Fly Drone / ドローン飛行のためのマイクロ波電力伝送のパワービーミング及び受電システムに関する研究Takabayashi, Nobuyuki 25 July 2022 (has links)
京都大学 / 新制・課程博士 / 博士(工学) / 甲第24147号 / 工博第5034号 / 新制||工||1786(附属図書館) / 京都大学大学院工学研究科電気工学専攻 / (主査)教授 篠原 真毅, 教授 小嶋 浩嗣, 教授 山本 衛 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM
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Reakce ryb při vzorkování vlečnými sítěmi / Fish behaviour in response to a trawl gearSAJDLOVÁ, Zuzana January 2012 (has links)
Předkládaná práce by měla čtenáře blíže seznámit s chováním ryb, které tito živočichové vykazují vůči vlečným sítím během vzorkování pelagiálu vodních těles. Zaměřuje se na oblast v ústí tralu, kde je spektrum reakcí nejširší. Některé specifické rysy chování jsou uvedeny na příkladech z mezinárodních výzkumů v teoretické části. Jsou zde rovněž přiblíženy základní techniky, používané při studiu chování ryb ve vztahu k vlečným sítím. Praktickou částí je dvouletý výzkum (2009 a 2011) chování ryb na českých údolních nádržích Želivka a Římov ve vztahu k tralovým sítím. Chování ryb v ústí pelagického tralu bylo monitorováno prostřednictvím vertikálního sonaru SIMRAD EK 60 o frekvenci 38 kHz. Předmětem výzkumu bylo studium reakcí jednotlivých ryb se zaměřením na vertikální složku jejich pohybu. Zjišťovali jsme rozdíly mezi denní a noční aktivitou ryb, rychlost a sklon ve vodním sloupci, přímočarost trajektorie pohybu, souvislost mezi velikostí ryb a jejich rychlostí, a v neposlední řadě také vliv abiotických faktorů, které únikové chování podstatně ovlivňují. Znalost tohoto typu chování pomůže vypovědět o selektivitě zařízení, kterou je vhodné znát pro efektivní průzkum zdejších nádrží. Stejně tak užitečné jsou nové informace o vlastním chování ryb, které jsou přínosem nejen pro ekologii.
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HIGH INTENSITY LASER POWER BEAMING FOR WIRELESS POWER TRANSMISSIONRaible, Daniel Edward 15 May 2008 (has links)
No description available.
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Wireless Power Transfer: Efficiency, Far Field, Directivity, and Phased Array AntennasAbigail Jubilee Kragt Finnell (10867179) 05 August 2021 (has links)
This thesis is an examination of one of the main technologies to be developed on the
path to Space Solar Power (SSP): Wireless Power Transfer (WPT), specifically power beaming. While SSP has been the main motivation for this body of work, other applications
of power beaming include ground-to-ground energy transfer, ground to low-flying satellite
wireless power transfer, mother-daughter satellite configurations, and even ground-to-car or
ground-to-flying-car power transfer. More broadly, Wireless Power Transfer falls under the
category of radio and microwave signals; with that in mind, some of the topics contained
within can even be applied to 5G or other RF applications. The main components of WPT
are signal transmission, propagation, and reception. This thesis focuses on the transmission
and propagation of wireless power signals, including beamforming with Phased Array Antennas (PAAs) and evaluations of transmission and propagation efficiency. Signals used to
transmit power long distances must be extremely directive in order to deliver the power at an
acceptable efficiency and to prevent excess power from interfering with other RF technology.
Phased array antennas offer one method of increasing the directivity of a transmitted beam
through off-axis cancellation from the multi-antenna source. Besides beamforming, another
focus of this work is on the equations used to describe the efficiency and far field distance
of transmitting antennas. Most previously used equations, including the Friis equation and
the Goubau equation, are formed by examining singleton antennas, and do not account for
the unique properties of antenna arrays. Updated equations and evaluation methods are
presented both for the far field and the efficiency of phased array antennas. Experimental
results corroborate the far field model and efficiency equation presented, and the implications
of these results regarding space solar power and other applications are discussed. The results
of this thesis are important to the applications of WPT previously mentioned, and can also
be used as a starting point for further WPT and SSP research, especially when looking at
the foundations of PAA technology.
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Wireless power transfer: a reconfigurable phased array with novel feeding architectureSzazynski, Mitchel H. 13 April 2018 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / This thesis proposes a reconfigurable phased array of antennas for wireless power transfer.
The array finds use in many applications, from drone destruction (for defense) to wireless
charging of robots and mobile devices. It utilizes a novel feeding architecture to greatly
reduce the number of high cost elements (such as amplifiers and phase shifters) as well as
the quantity of unused resources in the system.
Upon the instruction of the CPU, the array can separate into any number of subarrays,
each of which transmits power to a single receiver, steering its beam as the receiver changes
location. Currently dormant elements in the array can be used to provide position information
about the receivers, either via Radar, or by listening for beacons pulses from the
receiver.
All of this is made possible, with only 4 amplifiers and 3 phase shifters, by the proposed
4-Bus Method. The source signal is divided into four buses, which are respectively phase
shifted by 270 degrees, 180 degrees, 90 degrees, and 0 degrees (no shifter required) and
then amplified. The CPU calculates, based on the number and positions of the receivers
/ targets, what the amplitude and phase excitation must be at each element. Any phase
and amplitude which could be required can be achieved by simply adding together appropriate
quantities of the correct two buses. In order to achieve this, the key piece is the
variable power divider. These differ from Wilkinson dividers in that the dividing ratio can
be changed via an applied DC voltage. Therefore, at each junction, by properly diverting
the power levels on each phase bus to their proper location, complete delocalization of both
amplifiers and phase shifters can be achieved.
A method has also been developed which helps overcome the limitations of each variable
power divider. That is, in certain instances, it may be desirable to pass all the power
to a single output port or the other, which is not a possibility inherently possible with the
device. With the use of a unique combination of RF switches, the nodes achieve much
enhanced flexibility.
Finally, an intensive study is carried out, in an attempt to yield greater understanding,
as well as quick, useful approximations, of the behaviors of both rectangular and hexagonal arrays of various sizes and beam steering angles for wireless power.
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Free Space Optical Communications with High Intensity Laser Power BeamingRaible, Daniel Edward 15 August 2011 (has links)
No description available.
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Wave propagation in nonlinear periodic structuresNarisetti, Raj K. 20 December 2010 (has links)
A periodic structure consists of spatially repeating unit cells. From man-made multi-span bridges to naturally occurring atomic lattices, periodic structures are ubiquitous. The periodicity can be exploited to generate frequency bands within which elastic wave propagation is impeded. A limitation to the linear periodic structure is that the filtering properties depend only on the structural design and periodicity which implies that the dispersion characteristics are fixed unless the overall structure or the periodicity is altered.
The current research focuses on wave propagation in nonlinear periodic structures to explore tunability in filtering properties such as bandgaps, cut-off frequencies and response directionality. The first part of the research documents amplitude-dependent dispersion properties of weakly nonlinear periodic media through a general perturbation approach. The perturbation approach allows closed-form estimation of the effects of weak nonlinearities on wave propagation. Variation in bandstructure and bandgaps lead to tunable filtering and directional behavior. The latter is due to anisotropy in nonlinear interaction that generates low response regions, or "dead zones," within the structure.The general perturbation approach developed has also been applied to evaluate dispersion in a complex nonlinear periodic structure which is discretized using Finite Elements. The second part of the research focuses on wave dispersion in strongly nonlinear periodic structures which includes pre-compressed granular media as an example. Plane wave dispersion is studied through the harmonic balance method and it is shown that the cut-off frequencies and bandgaps vary significantly with wave amplitude. Acoustic wave beaming phenomenon is also observed in pre-compressed two-dimensional hexagonally packed granular media. Numerical simulations of wave propagation in finite lattices also demonstrated amplitude-dependent bandstructures and directional behavior so far observed.
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Development of an Integrated High Energy Density Capture and Storage System for Ultrafast Supply/Extended Energy Consumption ApplicationsDinca, Dragos 22 May 2017 (has links)
No description available.
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