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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.
11

Software defined radio

Alhasan, Raghda January 2016 (has links)
Software Defined Radio (SDR) technology is used to receive and transmit radio signals. Radio signals can be received using the SDR_sharp software that can be downloaded to a personal computer and combined with the RTL-SDR dongle hardware that is connected to the computer. This report gives a brief explanation of the SDR receiver, the supported software, and some applications that can be implemented with SDR. Moreover, it is shown how to install the SDR_sharp software and the hardware Zadig. After installation, wideband FM (WFM) reception and adjustment of RF gain and frequency error is illustrated. The reception of some national, regional and community/commercial stations that can be received in Växjö Sweden is presented. Keyword: Software defined radio, FM radio.
12

A Low-Cost Software-Defined Telemetry Receiver

Don, Michael L. 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 / The Army Research Laboratories has developed a PCM/FM telemetry receiver using a low-cost commercial software-defined radio (SDR). Whereas traditional radio systems are implemented in hardware, much of the functionality of software-defined radios is defined in software. This gives them the flexibility to accommodate military telemetry standards as well as other specialized functions. After a brief review of telecommunication theory, this paper describes the receiver implementation on a commercial SDR platform. Data rates up to 10 Mbs were obtained through the customization the SDR's field programmable gate array.
13

The Effects of Phase Noise on Trellis FM & SOQPSK Data Links

O'Cull, Douglas C. 10 1900 (has links)
ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, Nevada / Current IRIG standards provide guidelines for system phase noise and several manufactures provide receivers and transmitters that perform within this standard. However, legacy receivers and transmitters that do not meet the current IRIG standards are sometimes still used during a mission. This paper will address how phase noise outside of the current IRIG standard affects the performance of an FM data link when using a trellis demodulator, as well as the performance of an SOQPSK data link in a high phase noise environment. Bit error rate performance and test results at several different rates with various phase noise masks are presented in this paper.
14

A developmental broadcast frequency modulation station

Honnell, Martial Alfred 05 1900 (has links)
No description available.
15

WTMJ-FM, the Milwaukee Journal FM station, 1939-1966

Sterling, Christopher H., January 1967 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1967. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
16

An Experimental and Theoretical Analysis of Nitric Oxide in the Microcirculation

Namin, Shabnam M 27 June 2012 (has links)
Nitric Oxide (NO) is produced in the vascular endothelium where it then diffuses to the adjacent smooth muscle cells (SMC) activating agents known to regulate vascular tone. The close proximity of the site of NO production to the red blood cells (RBC) and its known fast consumption by hemoglobin, suggests that the blood will scavenge most of the NO produced. Therefore, it is unclear how NO is able to play its role in accomplishing vasodilation. Investigation of NO production and consumption rates will allow insight into this paradox. DAF-FM is a sensitive NO fluorescence probe widely used for qualitative assessment of cellular NO production. With the aid of a mathematical model of NO/DAF-FM reaction kinetics, experimental studies were conducted to calibrate the fluorescence signal showing that the slope of fluorescent intensity is proportional to [NO]2 and exhibits a saturation dependence on [DAF-FM]. In addition, experimental data exhibited a Km dependence on [NO]. This finding was incorporated into the model elucidating NO2 as the possible activating agent of DAF-FM. A calibration procedure was formed and applied to agonist stimulated cells, providing an estimated NO release rate of 0.418 ± 0.18 pmol/cm2s. To assess NO consumption by RBCs, measurements of the rate of NO consumption in a gas stream flowing on top of an RBC solution of specified Hematocrit (Hct) was performed. The consumption rate constant (kbl)in porcine RBCs at 25oC and 45% Hct was estimated to be 3500 + 700 s-1. kbl is highly dependent on Hct and can reach up to 9900 + 4000 s-1 for 60% Hct. The nonlinear dependence of kbl on Hct suggests a predominant role for extracellular diffusion in limiting NO uptake. Further simulations showed a linear relationship between varying NO production rates and NO availability in the SMCs utilizing the estimated NO consumption rate. The corresponding SMC [NO] level for the average NO production rate estimated was approximately 15.1 nM. With the aid of experimental and theoretical methods we were able to examine the NO paradox and exhibit that endothelial derived NO is able to escape scavenging by RBCs to diffuse to the SMCs.
17

On the Use of Rapid Prototyping for Designing PCM/FM Demodulators in FPGAS

Rice, Michael, Nelson, Brent, Padilla, Marc, Havican, Jared 10 1900 (has links)
ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, California / This paper describes the use of an efficient FPGA design flow, called Ogre, developed at BYU to design and implement PCM/FM demodulators. Ogre exploits the notion of reuse by taking advantage of a library of specially designed cores parameterized by XML metadata. A judicious choice of library cores, targeted to signal processing functions common to sampled data modulators and demodulators, reduces the design and test cycle time. We demonstrate this by using the tool to construct rapid prototypes of three different versions of FM demodulators and show that the bit error rate performance is comparable to demodulators on the market today.
18

WSMR Telemetry Capabilities: Today's Technology in Telemetry

Aguirre, Zoe, Beltran, Gabe 10 1900 (has links)
ITC/USA 2008 Conference Proceedings / The Forty-Fourth Annual International Telemetering Conference and Technical Exhibition / October 27-30, 2008 / Town and Country Resort & Convention Center, San Diego, California / White Sands Missile Range is the largest overland test range in North America occupying over 3,200 square miles in Southern New Mexico and nearby territory. One of the most critical test elements at White Sand Missile Range is it's capabilities in the telemetry field. Much significant advancement in technology has given WSMR and the entire electronics world the ability to achieve new levels of data acquisition that were not achievable a decade ago. And as attention to our nation's defense is of high priority, White Sands Missile Range provides to highest levels of telemetry competence in the Western Hemisphere.
19

An Enhancement of Existing RF Data Links Using Advanced Diversity Techniques

Melicher, Milos 10 1900 (has links)
ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, California / The theoretical capacity of communication channel in the presence of additive white Gaussian noise (AWGN) as defined by Shannon's channel capacity theorem has been well understood since 1940s. This theorem bounds the bit error rate (BER) of RF data links achievable for a particular noise level. The development in digital technology over the last decade has made it possible not just to design devices that operate close to the Shannon's limit, but also to explore techniques, such as best source and best data selectors, for further improvements in performance of RF data links where frequency, spatial or polar diverse reception is possible. This paper discusses an approach to improving quality of data links using an advanced diversity technique that does not select one source at a time but aligns and combines soft values from each. It shows how the overall bit error rate of RF data link can be improved by combining signals from multiple receivers and/or transmitters. Test results showing practical performance improvements are presented and discussed.
20

Modulation Index and FM Improvement for Analog TV

Baylor, J. Thomas 11 1900 (has links)
International Telemetering Conference Proceedings / October 29-November 02, 1990 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The concepts of modulation index and FM improvement are simple and straightforward when the modulating signals are sinesoidal. For a complex baseband waveform such as analog TV, the FM improvement may be seriously underestimated. A method for computer simulation of video waveforms and the resulting spectra are presented.

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