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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

A New Design Of Excitation Mechanism To Be Exploited By Modern Rf Excited Co2 Lasers

Kurucu, Salur Riza 01 September 2004 (has links) (PDF)
On this thesis work, design and construction of an up to date complete RF excitation system was intended. This excitation system is mainly based on highly efficient switching power generators and proper coupling of the power to the object plasma. This new excitation system design should answer the demands of today&#039 / s progressed CO2 lasers on various power ranges. Though it could be used by a large variety of applications including RF plasma and RF heating, on the first occasion in order to define design considerations, this system is to be exploited by RF excited fast flow and RF excited slab CO2 laser constructions.
72

Automatic Generation of Geometrically Parameterized Reduced Order Models for Integrated Spiral RF-Inductors

Daniel, Luca, White, Jacob K. 01 1900 (has links)
In this paper we describe an approach to generating low-order models of spiral inductors that accurately capture the dependence on both frequency and geometry (width and spacing) parameters. The approach is based on adapting a multiparameter Krylov-subspace based moment matching method to reducing an integral equation for the three dimensional electromagnetic behavior of the spiral inductor. The approach is demonstrated on a typical on-chip rectangular inductor. / Singapore-MIT Alliance (SMA)
73

Efficient Production Testing of High-Performance RF Modules and Systems using Low-Cost ATE

Srinivasan, Ganesh Parasuram 27 November 2006 (has links)
The proliferation of wireless communication devices in the recent past has increased the pressure on semiconductor manufacturers to produce quality radio frequency (RF) modules and systems at a low cost. This entails reducing their test cost as well, since the cost of testing modern RF devices can be up to 40% of their manufacturing cost. The high test cost of these devices can be mainly attributed to (a) the expensive nature of the RF automated test equipment (ATE) used to perform wafer-level and fully packaged RF functionality tests, (b) limited test point access for the application and capture of test signals, (c) the long test development and application times, and (d) the lack of diagnostic tools to evaluate and improve the performance of loadboards and test resources in high-volume tests. In this thesis, a framework for the efficient production testing of high-performance RF modules and systems using low-cost ATE is presented. This framework uses low-speed, low-resolution test resources to generate reliable tests for complex RF systems. Also, the test resources will be evaluated and improved ahead of high-volume tests to improve test yield and throughput. The components of the proposed framework are: (1) Genetic ATPG for reliable test stimulus generation using low-resolution test resources: A genetic algorithm (GA) based automatic test pattern generator (ATPG) to optimize the alternate test stimulus for reliable testing of complex RF systems using low-resolution, low-cost test resources. These test resources may be on-chip or off-chip. (2) Concurrent voltage/current alternate test methodology: A testing framework for efficiently testing the high-frequency specifications of RF systems using low-frequency spectral and/or transient current signatures. Suitable on-chip and/or off-chip design-for-test (DfT) resources are used to enable the source and capture operations at lower frequencies. (3) Loadboard checker: A checker tool to accurately characterize/diagnose the DfT resources on the RF loadboards used to enable test of RF devices/systems using low-cost ATE. (4) Advanced test signal processing algorithms: The performance of the low-cost ATE resources, in terms of their linearity/resolution, will be evaluated and improved to enable the accurate capture of the test response signals.
74

FLIGHT LINE TEST SET, IRIG TONE GENERATOR AND FLIGHT TERMINATION TRANSMITTER ON A PC CARD

Cirineo, Tony 10 1900 (has links)
International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper describes the development of a PC based IRIG tone generator and flight termination transmitter. The tone generator and flight termination transmitter card are part of a flight line test set. The test set has several PC based cards which include an S-Band telemetry receiver, a bit synchronizer, a decommutator, an encryption support card and the flight termination transmitter card. The test set can perform a complete end to end test of a weapon’s flight termination system prior to loading on an aircraft.
75

Integrated CMOS Doppler Radar : Power Amplifier Mixer

Sjöholm, Olof January 2016 (has links)
This thesis is based on a paper by V. Issakov, presented 2009, where a circuit of a merged power amplifier mixer solution was demonstrated. This work takes that solution and simplifies it for the use at a lower frequency. The implementation target is a Doppler radar application in CMOS that can detect humans in a range of 5 to 15 meters. This could be used as a burglar alarm or an automatic light switch. The report will present the background of Issakov’s work, basic theory used and the implementation of the final design. Simulations will show that the solution presented work, with a 15 dB conversion loss. This design performs well compared to reference mixers. With this report it will be shown that it is possible to make a simple and compact Doppler radar system in CMOS. / Denna avhandling bygger på en artikel av V. Issakov, presenterad 2009, där en lösning för att sammanslå en effektförstärkare med en mixer till en krets visades. Detta arbete tar denna lösning och förenklar det för användning vid en lägre frekvens. Målet är att implementera en dopplerradar i CMOS som kan detektera människor inom ett avstånd på 5 till 15 meter. Denna radar skulle kunna användas som ett inbrottslarm eller en automatisk strömbrytare. Rapporten kommer att presentera bakgrunden från Issakov’s arbete, grundläggande teori som används och genomförandet av det slutliga kretsschemat. Simuleringar visar att den presenterade lösningen fungerar, med en 15 dB konverteringsförlust. Denna konstruktion presterar väl jämfört med referens mixrar. Med denna rapport visas det att det är möjligt att göra ett enkelt och kompakt dopplerradarsystem i CMOS.
76

Exploring Radio Frequency Positioning Methods and Their Use in Determining User Context in Public Spaces

Guercio, Remy 01 January 2016 (has links)
RF positioning methods have various tradeoffs that make them suitable for differing applications. This thesis identifies the most prominent positioning methods and deter-mines their suitability for context aware applications in pub-lic spaces using a number of different factors. This thesis first explores the physical characteristics of GPS, GSM, 802.11 and Bluetooth focusing on coverage and accuracy in both a historical and forward looking context. Next, it explores what it means for an application to be context aware and how that translates into building applications that are used in the context of public places. This thesis then reflects on the intersection of the two and explores some challenges related to practical implementations. In order to further explore these challenges, it assesses a high accuracy use case of merging Bluetooth positioning with augmented reality and virtual reality applications. We find that in the last decade Bluetooth has made rapid advancements in relation to competing technologies, but it is still far from ideal in all situations, especially when the situation requires extremely high accuracy.
77

A VERSATILE PROGRAMMABLE FUNCTION RF ASIC FOR SPACE-BASED RF SYSTEMS

McMahon, Michael, Rhoads, Albert, Winter, Frank, Pierson, Graham 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / A programmable RF ASIC is described which provides most of the RF functions within a next generation S-band transponder for space applications. The unique 18-contact LCC device can be programmed to perform a variety of RF and analog functions. This single space qualified high speed bipolar "function toolbox" is used in 39 locations throughout the transponder to provide a flexible radio architecture. The ASIC design process, internal electrical design, circuit application, space environment performance, and RF testing of the RF ASIC are described. This proprietary part provides a space-qualified solution for RF circuitry that can be applied to a variety of space application products.
78

A TDRSS COMPATIBLE TRANSMITTER WITH AGILE RF ROUTING

Oney, Brad 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / An agile RF routing system has been developed which utilizes phasing techniques to direct signal power to any one of four orthogonally mounted antennae, or either set of two antennae mounted 180° apart on a launch vehicle. The system has been integrated into a telemetry transmitter and has shown superior performance to traditional methods of antennae switching. The unit is self-correcting to maintain maximum RF power at the desired antenna port(s) across a dynamic mission environment. Due to its low loss and high reliability, this method of antennae switching provides a robust RF link.
79

RADIO FREQUENCY PATH CHARACTERIZATION FOR WIDE BAND QUADRATURE AMPLITUDE MODULATION

Bracht, Roger 10 1900 (has links)
International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California / Remote, high speed, high explosive wave front monitoring requires very high bandwidth telemetry to allow transmission of diagnostic data before the explosion destroys the sensor system itself. The main motivation for this study is that no known existing implementation of this sort has been applied to realistic weapons environments. These facts have prompted the research and gathering of data that can be used to extrapolate towards finding the best modulation method for this application. In addition to research of similar existing analysis and testing operations, data was recently captured from a Joint Test Assembly (JTA) Air Launched Cruise Missile (ALCM) flight.
80

The Performance Test of an Initial iNET-Like RF Network Using a Tethered Aerostat in Japan

Tanaka, Toshihisa, Aoyama, Daiki, Ito, Sei 10 1900 (has links)
ITC/USA 2015 Conference Proceedings / The Fifty-First Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2015 / Bally's Hotel & Convention Center, Las Vegas, NV / Through the use of early iNET-prototype IP Transceiver technology, Kawasaki Heavy Industries, Ltd. (KHI) has been able to communicate with flight test vehicles during a recent research program. This technology provides a two-way high-capacity communication that has not been achieved with conventional telemetry and can be used not only for flight testing, but also for rescue work. KHI has been authorized to use S-band IP Transceivers since last year in Japan, and various communication tests have been performed. This paper describes Japan's first simulation of an iNET RF network which incorporated testing that performed data backfill, voice communication and video transmission. A data backfilling test was performed using retransmit of lock-off data (which is lost as the aircraft maneuvers) on command from the ground station. Moreover, a tethered aerostat is considered a very useful communication relay platform in the event of a large-scale disaster which results in the destruction of infrastructure. Also, the silence of an aerostat can be very important for search and rescue work.

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