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PHOTONIC REMOTING OF THE KWAJALEIN MISSILE RANGE POST IMPACT TELEMETRY SYSTEMAbouzahra, Mohamed D., Robey, Frank C., Henion, Scott 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper describes the design, configuration, testing, and performance of a Fiber
Optic Link used to transmit the signals from a remotely located S-band telemetry system
to the main facility at the Kwajalein Missile Range (KMR). This fiber optic system
demonstrates for the first time the feasibility of linking RF data from multiple antennas
via a single fiber and over a nearly 100-km distance. Measured data of key link
parameters such as gain, bit-error-rate, crosstalk, phase and gain stability, dynamic range,
and noise figure are presented.
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RADIO FREQUENCY OVERVIEW OF THE HIGH EXPLOSIVE RADIO TELEMETRY PROJECTBracht, Roger, Dimsdle, Jeff, Rich, Dave, Smith, Frank 10 1900 (has links)
International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California / High explosive radio telemetry (HERT) is a project that is being developed jointly by Los
Alamos National Laboratory and AlliedSignal FM&T. The ultimate goal is to develop a
small, modular telemetry system capable of high-speed detection of explosive events,
with an accuracy on the order of 10 nanoseconds. The reliable telemetry of this data,
from a high-speed missile trajectory, is a very challenging opportunity. All captured data
must be transmitted in less than 20 microseconds of time duration. This requires a high
bits/Hertz microwave telemetry modulation code to insure transmission of the data within
the limited time interval available.
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3-D Ray-Tracing Simulations for 5.7GHz RF Indoor Position Location SystemAnnamraju, Venu, Burns, Thomas 10 1900 (has links)
International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California / The objective of the project is to continuously track a handheld device in an office, with centimeter accuracy in the three dimensions. A 3-D ray-tracing algorithm has been developed to simulate the impulse response of the indoor channel. The algorithm can evaluate the impulse response at multiple receiver locations. Non-linear optimization has been used to eliminate the need for multiple runs of simulation. The optimization program also significantly reduces the number of rays launched. The algorithm incorporates bandwidth effects on multipath resolution of the system.
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LOW-COST TELEMETRY USING FREQUENCY HOPPING AND THE TRF6900™ TRANSCEIVER1Thornér, Carl-Einar I., Iltis, Ronald A. 10 1900 (has links)
International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California / The ISM bands have opened up new opportunities for telemetry using spread-spectrum communications. A low-cost frequency-hopping radio is described here for the 900 MHz ISM band that can be programmed with a wide range of hop and data rates. The ‘C6201 DSP from TI is used to control the frequency and data rate of the TI TRF6900 transceiver chip using a custom interface of the 6201 EVM board to the serial I/O on the 6900 evaluation board.
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BANDWIDTH EFFICIENT MODULATION SCHEMES FOR FUTURE TT&C APPLICATIONSNguyen, Tien M., Nguyen, Hung H., Yoh, James, Sklar, Dean J., Eng, Thomas 10 1900 (has links)
International Telemetering Conference Proceedings / October 22-25, 2001 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper presents initial results of an investigation on bandwidth efficient waveforms for telemetry, tracking and commands (TT&C). Included in the investigation are waveforms that are currently being considered by the International Consultative Committee for Space Data Systems (CCSDS) and American Institute of Aeronautics and Astronautics (AIAA) for standards, advanced waveforms and others that have the potential to become future standards. The goal of this investigation is to recommend a suite of bandwidth efficient modulation schemes for further investigation. This suite of modulation scheme should be suitable for various TT&C applications with data rates ranging from a few hundreds Bit Per Second (bps) to a few hundreds Mega bps (Mbps). First, the philosophy of waveform evaluation is described. The description includes a list of waveform attributes leading to quantitative and qualitative figures of merit for bandwidth efficient waveforms. Then quantitative results for the two most important waveform attributes (bandwidth efficiency and bit error rate performance) are presented. These results will be used by a follow-on study to significantly reduce the number of candidate waveforms, so that all attributes can be more thoroughly evaluated.
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EASTERN RANGE TITAN IV/CENTAUR-TDRSS OPERATIONAL COMPATIBILITY TESTINGBocchino, Chris, Hamilton, William 10 1900 (has links)
International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / The future of range operations in the area of expendable launch vehicle (ELV) support is
unquestionably headed in the direction of space-based rather than land- or air-based assets
for such functions as metric tracking or telemetry data collection. To this end, an effort
was recently completed by the Air Force’s Eastern Range (ER) to certify NASA’s
Tracking and Data Relay Satellite System (TDRSS) as a viable and operational asset to be
used for telemetry coverage during future Titan IV/Centaur launches. The test plan
developed to demonstrate this capability consisted of three parts: 1) a bit error rate test; 2)
a bit-by-bit compare of data recorded via conventional means vice the TDRSS network
while the vehicle was radiating in a fixed position from the pad; and 3) an in-flight
demonstration to ensure positive radio frequency (RF) link and usable data during critical
periods of telemetry collection. The subsequent approval by the Air Force of this approach
allows future launch vehicle contractors a relatively inexpensive and reliable means of
telemetry data collection even when launch trajectories are out of sight of land-based
assets or when land- or aircraft-based assets are not available for support.
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Development of microfluidic packages on multilayer organic substrate for cooling and tuning RF circuitsLemtiri Chlieh, Outmane 07 January 2016 (has links)
The objective of this PhD research was to design and implement novel microfluidic radio-frequency (RF) structures on multilayer organic substrates for cooling and tuning purposes. The different designs were implemented to target applications up to C-band (4 GHz – 8 GHz) frequencies. The system-on-package (SoP) solution adopted throughout this work is well adapted for such designs where there is a need to integrate the functionality of different sub-components into a single hybrid fully packaged system. The first part of the thesis is dedicated to the study of a specific liquid cooling scheme using integrated microchannels on organics placed beneath different types of heat sources. A 1 W gallium nitride (GaN) die was cooled using this method and an analysis is presented regarding the cases where the coolant is static or dynamic inside the microchannel. The second part of the thesis deals with microfluidically reconfigurable microstrip RF circuits, mainly bandpass filters and power amplifiers (PAs). The microfluidic tuning technique is based on the change in the effective dielectric constant that the RF signal “sees” when traveling above two microchannels with different fluids. This technique was used to shift the frequency response of an L-band microstrip bandpass filter by replacing DI water with acetone inside a 60 mil micro-machined cavity. This technique was also used to design reconfigurable matching networks which constitute the main part of the proposed tunable GaN-based PA for S- and C-band applications. The final part of the thesis expands the previous results by combining both cooling and tuning in a single RF design. To prove the concept, cooling and tuning microchannels were integrated into a single package to cool a GaN-based PA and tune its frequency response at the same time from 2.4 GHz to 5.8 GHz and vice versa.
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RF/microwave absorbing nanoparticles and hyperthermiaCook, Jason Ray 31 August 2010 (has links)
The primary purpose of this work was to evaluate the capability of nanoparticles to transform electromagnetic energy at microwave frequencies into therapeutic heating. Targeted nanoparticles, in conjunction with microwave irradiation, can increase the temperatures of the targeted area over the peripheral region. Therefore, to become clinically viable, microwave absorbing nanoparticles must first be identified, and a system to monitor the treatment must be developed.
In this study, ultrasound temperature imaging was used to monitor the temperature of deep lying structures. First, a material-dependent quantity to correlate the temperature induced changes in ultrasound images (i.e. apparent time shifts) to differential temperatures was gathered for a tissue-mimicking phantom, porcine longissimus dorsi muscle, and porcine fat. Then microwave nanoabsorbers were identified using an infrared radiometer. The determined nanoabsorbers were then injected into ex-vivo porcine longissimus dorsi muscle tissue. Ultrasound imaging frames were gathered during microwave treatment of the inoculated tissue. Finally, the ultrasound frames were analyzed using the correlation between temperature and apparent shifts in ultrasound for porcine muscle tissue. The outcome was depth-resolved temperature profiles of the ex-vivo porcine muscle during treatment.
The results of this study show that magnetite is a microwave nanoabsorber that increases the targeted temperature of microwave hyperthermia treatments. Overall, there is clinical potential to use microwave nanoabsorbers to increase the efficiency of microwave hyperthermia treatments. / text
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Ferroelectric Na0.5K0.5NbO3 as an electro-optic materialBlomqvist, Mats January 2002 (has links)
<p>Ferroelectrics are a group of advanced electronic materialswith a wide variety of properties useful in applications suchas memory devices, resonators and filters, infrared sensors,microelectromechanical systems, and optical waveguides andmodulators. Among the oxide perovskite-structured ferroelectricthin film materials sodium potassium niobate or Na0.5K0.5NbO3(NKN) has recently emerged as one of the most promisingmaterials in microwave applications due to high dielectrictunability and low dielectric loss. This licentiate thesispresents results on growth and structural, optical, andelectrical characterization of Na0.5K0.5NbO3 thin films. Thefilms were deposited by rf-magnetron sputtering of astoichiometric, high density, ceramic Na0.5K0.5NbO3 target ontosingle crystal LaAlO3 and Al2O3, and polycrystalline Pt80Ir20substrates. By x-ray diffractometry, NKN films on c-axisoriented LaAlO3 substrates were found to grow epitaxially,whereas films on hexagonal sapphire and polycrystallinePt80Ir20 substrates were found to be preferentially (00l)oriented. Optical and waveguiding properties of theNa0.5K0.5NbO3/Al2O3 heterostructure were characterized using aprism-coupling technique. Sharp and distinguishable transversemagnetic (TM) and electric (TE) propagation modes wereobserved. The extraordinary and ordinary refractive indiceswere calculated to ne = 2.216±0.003 and no =2.247±0.002 for a 2.0 μm thick film at λ = 632.8nm. This implies a birefringence Δn = ne - no =-0.031±0.003 in the film. The ferroelectric state inNKN/Pt80Ir20 films at room temperature was indicated by apolarization loop with polarization as high as 33.4 μC/cm2at 700 kV/cm, remnant polarization of 9.9 μC/cm2 andcoercive field of 91 kV/cm. Current-voltage characteristics ofvertical Au/NKN/Pt80Ir20 capacitive cells and planar Au/NKN/LaAlO3 interdigital capacitors (IDCs) showed very goodinsulating properties, with the leakage current density for anNKN IDC on the order of 30 nA/cm2 at 400 kV/cm. Rf dielectricspectroscopy demonstrated low loss, low frequency dispersion,and high voltage tunability. At 1 MHz NKN/LaAlO3 showed adissipation factor tan δ of 0.010 and a tunability of 16.5% at 200 kV/cm. For the same structure the frequencydispersion, Δεr, between 1 kHz and 1 MHz was 8.5%.</p><p><b>Key words:</b>ferroelectrics, sodium potassium niobates,thin films, rf-magnetron sputtering, waveguiding, refractiveindex, prism coupling, dielectric tunability</p>
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An investigation of dusty plasmasTomme, Edward B. January 2000 (has links)
No description available.
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