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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

Strategies for estimating atmospheric water vapour using ground-based GPS receivers in Australia

Agustan, January 2004 (has links)
The Global Positioning System (GPS) of navigation satellites was first developed for global navigation and position determination purposes. Signals from satellites are delayed by the Earths neutral atmosphere on propagating to ground-based receivers, termed the tropospheric delay. Although an unwanted term for precise positioning, the tropospheric delay may be converted to atmospheric water vapour, which is a vital parameter for weather forecasting.This research investigates the optimum GPS processing strategy to estimate atmospheric water vapour derived from ground-based GPS receivers particularly in the Australian region. For this purpose, GPS data observations from GPS permanent stations across Australia, mainly from the Australian Regional GPS Network, will be processed using scientific GPS software in post-processed mode and near real-time mode.This research shows that by applying high accuracy GPS data processing, the tropospheric delay could be estimated precisely. The quality of GPS data processing is indicated by the station coordinates repeatability since the coordinates can gauge at least a coarse assessment of the ability of the processing method to estimate the tropospheric delay.The precipitable water can be estimated from the wet component after separating the tropospheric delay into dry and wet components. High accuracy GPS data processing is dependent on the best choice of processing strategies, and the correct application of error-correction models and a priori constraints. This research finds that the GPS- PW estimation agrees with Radiosonde-PW estimation with an average of standard deviation at 2.5mm level for post-processed strategy and 2.8mm for near real-time strategy. The standard deviation of tropospheric parameter estimates is 1.1mm for post-processed strategy and 1.5mm for near real-time strategy.
12

AIR-GROUND TELEMETRY SYSTEMS FOR RESEARCH HELICOPTERS

Kasper, Eugene F., Leong, Gary 10 1900 (has links)
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper describes the development of a compact mobile telemetry system using commercial-off-the-shelf components. The personal computer-based systems support microwave pulse code modulation and serial spread-spectrum radio modem telemetry. The mobile ground station provides data display and archiving of test activities, air-ground communications between experimenters and the flight test crew, and acts as a flight test Differential Global Positioning System base station. The success of the systems indicates that functional telemetry capabilities can be established for small flight test programs at modest cost.
13

Current Status of Integrating GPS and Flight Termination Capabilities into a Missile Telemetry Section

Kujiraoka, Scott R., Fielder, Russell G. 10 1900 (has links)
ITC/USA 2006 Conference Proceedings / The Forty-Second Annual International Telemetering Conference and Technical Exhibition / October 23-26, 2006 / Town and Country Resort & Convention Center, San Diego, California / Last year (2005), a paper discussed the efforts of integrating Joint Advanced Missile Instrumentation (JAMI) Program components (JAMI TSPI Unit - JTU, and the Flight Termination Safe & Arm device - FTS&A), commercial off the shelf parts (Flight Termination Receivers, Telemetry Transmitter, Encryptor and Thermal Batteries) and in-house developed devices (PCM Encoder and Tri-band Antenna with integrated Limiter, Filter, & Amplifier) into a five-inch diameter Missile Telemetry (TM) Section. This retrofitted missile would be captive-carried on a F/A-18 jet. This paper is a continuation of that one presented at the 2005 International Telemetry Conference (ITC) Symposium. It annotates the latest status of the JAMI Effort, as well as the Follow-On Effort to qualify the Missile TM Section for an actual missile firing. This would include the developmental and flight qualification efforts for the Explosive Train (Detonation Cord-to-Cutter Ring Assembly) and Thermal Batteries.
14

TELEMETRY GROUND STATION CONFIGURATION FOR THE JOINT ADVANCED MISSILE INSTRUMENTATION (JAMI) TIME SPACE POSITION INFORMATION (TSPI) UNIT (JTU)

Meyer, Steven J. 10 1900 (has links)
ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada / The Joint Advance Missile Instrumentation (JAMI) program has developed a Time Space Position Information (TSPI) unit (JTU). The JTU employs a novel use of GPS technology and inertial measurement units (IMU) to provide a real time trajectory for high dynamic missile systems. The GPS system can function during high g maneuvers that an air-to-air missile might encounter. The IMU is decoupled from the GPS sensor. The IMU data is a secondary navigation source for the JTU and will provide platform attitude. The GPS data and IMU data are sent to the ground in a telemetry packet called TUMS (TSPI Unit Message Structure). The TUMS packet is sent to a computer that hosts the JAMI Data Processing (JDP) software, which performs a Kalmam filter on the GPS and IMU data to provide a real-time TSPI solution to the range displays. This paper focuses on the equipment and software needed at a telemetry ground station to display the real time TPSI solution on the range displays. It includes an overview of the system data flow. This overview should help a potential user of the system understand what is involved in running the JAMI system. The post mission tools to provide an accurate trajectory and end-game scoring will not be discussed in this paper.
15

TEST AND EVALUATION OF GPS/DR APPLICATION FOR CAR NAVIGATION SYSTEM

Dongkai, Yang, Yanhong, Kou, Zhi, Chen, Qishan, Zhang, Aigong, Xu 10 1900 (has links)
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Global Positioning System (GPS) was analyzed in terms of its repeatable accuracy, UTM projection for 2D plane coordinate system, satellite visibility performance and the horizontal dilution of positioning (HDOP). The principle of Dead Reckoning together with body coordinate system transformation was introduced. The complementary performance of GPS and DR, and GPS/DR integration using gyroscope and accelerometer were given. Test results were demonstrated that the repeatable accuracy of GPS alone is about 10 meters in open air, and DR can provide continuous positioning output within sufficient accuracy when GPS signal is outage.
16

Adding Flight Termination Capability to a Missile Telemetry Section

Kujiraoka, Scott R., Fielder, Russell G., Sandberg, Alvia D. 10 1900 (has links)
ITC/USA 2009 Conference Proceedings / The Forty-Fifth Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2009 / Riviera Hotel & Convention Center, Las Vegas, Nevada / Past presented papers [1,2] have discussed the integration efforts of incorporating Central Test & Evaluation Investment Program (CTEIP) sponsored Joint Advanced Missile Instrumentation (JAMI) components (namely the JAMI TSPI Unit-JTU), Commercial off the Shelf (COTS) parts (e.g. ARTM Tier I SO-QPSK Transmitter, Encryptor and Thermal Battery), and in-house developed devices (such as PCM Encoder and Dual Band Antenna) into a five-inch diameter Missile Telemetry (TM) Section. A prototype of this TM Section has been built up and integrated into an All Up Round (AUR) Missile and twice flown as a Captive Carried Test Missile (CTM) on an F/A-18 jet with great success. This TM Section has passed all flight qualification testing (including environmental and electro-magnetic interference-EMI tests). This paper will detail the current efforts to incorporate Flight Termination System (FTS) capabilities into this TM section. In addition, the effort to upgrade some Navy and Air Force Test Ranges (with JAMI Ground Stations and Decommutators/Demodulators) to track and gather data from this Missile containing the new TM section will be discussed.
17

Current Status of Adding GPS Tracking Capability to a Missile Telemetry Section

Kujiroaoka, Scott R., Fielder, Russell G., Sandberg, Alvia D. 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 / Past presented papers have discussed the integration efforts of incorporating Central Test & Evaluation Investment Program (CTEIP) sponsored Joint Advanced Missile Instrumentation (JAMI) components (namely the JAMI TSPI Unit-JTU), Commercial off the Shelf (COTS) parts (e.g. ARTM Tier I SO-QPSK Transmitter, Encryptor and Thermal Battery), and in-house developed devices (such as PCM Encoder and Dual Band Antenna) into a five-inch diameter Missile Telemetry (TM) Section. A prototype of this TM Section has been built up and integrated into an All Up Round (AUR) Missile and twice flown as a Captive Carried Test Missile (CTM) on an F/A-18 jet with great success. This TM Section is in the process of undergoing flight qualification testing (including environmental and electro-magnetic interference-EMI tests). After which it will be ready for mass production. This paper will detail these current efforts. In addition, the effort to upgrade some Navy and Air Force Test Ranges (with JAMI Ground Stations and Decommutators/Demodulators) to track and gather data from this Missile containing the new TM section will be discussed. Future plans to incorporate Flight Termination System (FTS) capabilities into the TM section will be covered as well.
18

GPS Receiver Testing on the Supersonic Naval Ordnance Research Track (SNORT)

Meyer, Steven J. 10 1900 (has links)
International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada / There is an interest in using Global Positioning System (GPS) receivers to find: Time Space Position Information (TSPI), miss distances between a missile and target, and using the data real time as an independent tracking aid for range safety. Ashtech, Inc. has several standalone GPS receivers they believe can work at high g levels. This paper investigates how the Ashtech GPS receivers work under high g loading in one axis. The telemetry system used to collect data from the receivers and the reconstruction of the data will also be discussed. The test was done at SNORT (Supersonic Naval Ordnance Research Track) located at NAWS, China Lake, CA. The g level obtained was about +23 g’s with a deceleration of -15 g’s. The velocity reached was about Mach 2.0. A summary of the errors is included.
19

INTELLIGENT VEHICLE NAVIGATION SYSTEM CONNECTED WITH INTERNET

Bingxin, Yi, Qishan, Zhang, Shengxi, Ding 10 1900 (has links)
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The intelligent vehicle navigation system is a multifunctional and complex integrated system that uses autonomous vehicle navigation, geography information, database system, computer technology, multimedia technology and wireless communication. In this paper, an autonomous navigation system based on embedded hardware and embedded operation system that is Linux is proposed. The system has advantages of low cost, small mass, multifunction and high stability, especially connecting with Internet.
20

GPS: THE LOGICAL TOOL FOR PRECISION TRACKING IN SPACE

Hoefener, Carl E. 11 1900 (has links)
International Telemetering Conference Proceedings / November 04-07, 1991 / Riviera Hotel and Convention Center, Las Vegas, Nevada / As we develop more space vehicles, a pressing requirement emerges to provide precision tracking information. This need for exact time and space-position information (TSPI) persists whether developing and testing space weapons or locating the precise position of intelligence-gathering satellites. Because this is a worldwide tracking requirement, the use of conventional tracking techniques such as radar is precluded. Fortunately the Global Positioning System (GPS) is now in place and can provide the tracking information required. GPS offers two techniques for tracking space vehicles. A GPS receiver can be installed on the vehicle to determine the position that is then relayed to a ground terminal, or a GPS frequency translator can be used to compute the vehicle position at the master groundsite. Since both techniques have been proven satisfactory, the specific tracking requirement determines the method selected. For the flight tests of the Exoatmospheric Reentry-Vehicle Interceptor Subsystem (ERIS), the GPS frequency translator technique is used. A GPS frequency translator is installed on the target (a reentry-vehicle launched on a Minuteman from Vandenberg), and a translator is also installed on the ERIS, which is launched from Meck Island in the Kwajalein Atoll. The GPS frequency translator approach was chosen for these tests for a variety of reasons, the most important of which were the limited instrumentation space on the target and interceptor, the extreme dynamics of the interceptor, the tracking accuracy required, and the range at which the operation must be tracked. For the tracking of orbiting satellites, a GPS receiver can be flown on the satellite with its derived position information continuously stored. This data can then be dumped as the satellite passes over a selected groundsite.

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