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Electrical and Electronics Commons

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Electrical engineering

Theses/Dissertations

2013

Articles 1 - 4 of 4

Full-Text Articles in Electrical and Electronics

High Performance Rf Control Devices Using Capacitively Coupled Contacts (C3) Over Iii-N Heterostructures, Faisal Jahan Jan 2013

High Performance Rf Control Devices Using Capacitively Coupled Contacts (C3) Over Iii-N Heterostructures, Faisal Jahan

Theses and Dissertations

RF switches, power limiters and other control devices are essential components of modern RF systems. RF switches are important parts of wireless modules of various devices such as laptops, tablets, cell phones etc. and key components of satellites communication systems, radars, multi-band wireless and aerospace communications, phased array antennas. RF Power limiters (PL) are also important components of RF systems protecting linear amplifiers, detectors etc. from high-power stress. Traditionally, RF switches are fabricated using pin diodes or MEMS, Si MOSFETs or GaAs HEMTs. RF PLs are typically implemented using Schottky or pin-diodes. Traditional devices used in RF switch and PLs …


Passive Equalizer Topology Analysis For Signal Integrity Applications, Kuo-Lun Yen Jan 2013

Passive Equalizer Topology Analysis For Signal Integrity Applications, Kuo-Lun Yen

Theses and Dissertations

In high-speed, high density PCB bus systems, high frequency signal losses and crosstalk can have great impacts on signal integrity and digital timing, which can distort transmitted signals, worsen eye diagrams, and attenuate signal amplitudes. Also, these impacts make digital signals and their energy smearing over multiple bit positions as known as jitters, and cause the phenomenon of inter-symbol interference (ISI) in digital signal transmissions.

The main objective of this thesis is to analyze and develop efficient topology circuits for compensating bus system high frequency losses by using equalization techniques. The thesis has focused on study of various practical and …


Ultrawideband (Uwb) And Reconfigurable Antennas - New Concepts For Conformal Load Bearing Antenna Structures (Clas), Nicholas Bishop Jan 2013

Ultrawideband (Uwb) And Reconfigurable Antennas - New Concepts For Conformal Load Bearing Antenna Structures (Clas), Nicholas Bishop

Theses and Dissertations

Conformal antennas have been increasingly playing an important role in a vast number wireless of communication applications. More specifically, Conformal Load Bearing Antenna Structures (CLAS) have drawn a great deal of interest among researchers and engineers because of their advantages of multiple functionality, e.g. antenna and structure both. The objectives of this thesis are to investigate and design innovative conformal Ultrawideband (UWB) endfire antenna arrays and reconfigurable aperture coupled pixel patch antennas both of which are good candidates for CLAS. First, a broadband VHF-UHF end-fire Yagi-Uda array is proposed for possible air vehicle integration and operation within the 240-465 MHz …


Iii-V Nitride Micro- And Nano-Scale Cantilevers For Multimodal Sensing Applications, Ehtesham Bin Quddus Jan 2013

Iii-V Nitride Micro- And Nano-Scale Cantilevers For Multimodal Sensing Applications, Ehtesham Bin Quddus

Theses and Dissertations

Recent research trends in chemical and biological sensing have been geared toward developing molecular sensor devices that are fast, label free, miniaturized and portable. The performance of these devices can be dramatically improved by utilizing multimodal detection techniques, new materials and micro-/nanofabrication technologies. This is especially true for micro-/nanoscale cantilever sensors, which undergo changes in mechanical or electrical properties upon the specific binding of molecules. To develop the sensor devices with the above attributes, we utilized III-V nitride materials: InN nanowires for realizing nanoscale cantilevers and AlGaN/GaN heterostuctures with or without embedded HFETs, for developing microcantilevers. There are mainly two …