Spelling suggestions: "subject:"RF engineering"" "subject:"RF ingineering""
1 |
Microwave Photonic Applications - From Chip Level to System LevelNeumann, Niels 06 May 2021 (has links)
Die Vermischung von Mikrowellen- und optischen Technologien – Mikrowellenphotonik – ist ein neu aufkommendes Feld mit hohem Potential. Durch die Nutzung der Vorzüge beider Welten hat die Mikrowellenphotonik viele Anwendungsfälle und ist gerade erst am Beginn ihrer Erfolgsgeschichte. Der Weg für neue Konzepte, neue Komponenten und neue Anwendungen wird dadurch geebnet, dass ein höherer Grad an Integration sowie neue Technologien wie Silicon Photonics verfügbar sind. In diesem Werk werden zuerst die notwendigen grundlegenden Basiskomponenten – optische Quelle, elektro-optische Wandlung, Übertragungsmedium und opto-elektrische Wandlung – eingeführt. Mithilfe spezifischer Anwendungsbeispiele, die von Chipebene bis hin zur Systemebene reichen, wird der elektrooptische Codesign-Prozess veranschaulicht. Schließlich werden zukünftige Ausrichtungen wie die Unterstützung von elektrischen Trägern im Millimeterwellen- und THz-Bereich sowie Realisierungsoptionen in integrierter Optik und Nanophotonik diskutiert. / The hybridization between microwave and optical technologies – microwave photonics – is an emerging field with high potential. Benefitting from the best of both worlds, microwave photonics has many use cases and is just at the beginning of its success story. The availability of a higher degree of integration and new technologies such as silicon photonics paves the way for new concepts, new components and new applications. In this work, first, the necessary basic building blocks – optical source, electro-optical conversion, transmission medium and opto-electrical conversion – are introduced. With the help of specific application examples ranging from chip level to system level, the electro-optical co-design process for microwave photonic systems is illustrated. Finally, future directions such as the support of electrical carriers in the millimeter wave and THz range and realization options in integrated optics and nanophotonics are discussed.
|
2 |
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.
|
Page generated in 0.049 seconds