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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.
21

A software defined GPS signal simulator design

Pan, Zhenhe 17 March 2014 (has links)
The Global Positioning System (GPS) signal simulator plays a critical role in developing and testing GPS receivers. Unfortunately, very few commercial GPS signal simulators are user-friendly for security researchers because they fail to generate abnormal GPS signals, which are fundamentally important. In this thesis, we develop a cost efficient software defined GPS signal simulator. To reduce the design complexity, we make some reasonable assumptions about the GPS system. This simulator is able to generate clean GPS signals, as well as polluted GPS signals by jamming, multi-path, and spoofing interferences. In addition to simulating GPS signals for a single stand alone antenna, our simulator is also able to simulate GPS signals for multiple antennas, simultaneously. These features of the simulator will immensely help the security researchers in the GPS community. / Master of Science
22

SIGNAL TDOA BASED HIGH RESOLUTION TSPI

Humpherys, Brian 10 1900 (has links)
International Telemetering Conference Proceedings / October 17-20, 1994 / Town & Country Hotel and Conference Center, San Diego, California / This paper describes a method for determining high resolution time, space, and position information for a test range flight vehicle using four tracking receivers. Equipped with GPS time systems, each receiver records the exact time at which a time marker embedded in the transmitted TM data stream is received. With this information, the time difference of arrival for the time markers at three of the receivers can be calculated referenced to the fourth. Using this time difference, the position of the transmitter can be determined. The accuracy with which the received signal time delay can be calculated depends on the accuracy of the GPS time system at each receiver. The effect of time accuracy on positional resolution is evaluated.
23

A STATUS REPORT OF THE JOINT ADVANCED MISSILE INSTRUMENTATION PROGRAM AN OFFICE OF THE SECRETARY OF DEFENSE CENTRAL TEST AND EVALUATION INVESTMENT PROGRAM INITIATIVE

Scofield, Don, Powell, Dave 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / Joint Advanced Missile Instrumentation (JAMI), a 1997 new-start multi-year Central Test and Evaluation Investment Program (CTEIP), is developing advanced telemetry system components that can be used in an integrated instrumentation package for tri-service small missile test and training applications. JAMI will provide telemetry, Time-Space-Position Information (TSPI), flight termination and end-game vector scoring in a low cost, modular package that will allow world-wide test and training- eliminating, in most cases, the need for range-specific (or multi-system) facilities. JAMI will incorporate Global Positioning System (GPS)-based technology as the TSPI and vector scoring engine, and is completing the development of a solid state programmable safe and arm device for flight safety applications. The JAMI program has progressed into Phase 2 and full-scale development of advanced GPS technologies. This paper discusses the progress of the program during the past year and the efforts planned for fiscal year 2000. Testing of GPS receivers and problems encountered in programming GPS simulator for missile flight profiles are discussed.
24

EVALUATION OF GPS RECEIVER PERFORMANCE UNDER HIGH DYNAMIC CONDITIONS

Cunningham, James P., Khoe, Paula K., Hermann, Bruce R., Evans, Alan G., Merts, John H. 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / Global Positioning System (GPS) sensors have the potential to provide precise position, velocity, and timing information in high dynamic applications. Missile flight-testing is one such application where accurate relative positions are important. GPS instrumentation can provide the high accuracy while offering both significant cost savings and improved confidence in the test results when compared to existing methods. To date, the use of GPS in missile flight-testing has been limited due to a lack of demonstrated GPS receiver tracking capability in high dynamics. This paper evaluates several currently available GPS receivers for both their tracking capability and their measurement accuracy in high dynamic environments.
25

A STATUS REPORT OF THE JOINT ADVANCED MISSILE INSTRUMENTATION PROGRAM AN OFFICE OF THE SECRETARY OF DEFENSE CENTRAL TEST AND EVALUATION INVESTMENT PROGRAM INITIATIVE

Scofield, Don, Powell, Dave 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Joint Advanced Missile Instrumentation (JAMI), a 1997 new-start multi-year Central Test and Evaluation Investment Program (CTEIP), is developing advanced telemetry system components that can be used in an integrated instrumentation package for tri-service small missile test and training applications. JAMI will provide telemetry, Time-Space-Position Information (TSPI), flight termination and end-game vector scoring in a low cost, modular package that will allow world-wide test and training- eliminating, in most cases, the need for range-specific (or multi-system) facilities. JAMI will incorporate Global Positioning System (GPS)-based technology as the TSPI and vector scoring engine, and address the feasibility of a solid state programmable safe and arm. This paper discusses the progress of the program during the Test Technology Development and Demonstration (TTD&D) phase and the efforts planned for fiscal year 1999. Preliminary testing of GPS receivers and conformal GPS antennas on missile platforms are discussed.
26

A STATUS REPORT OF THE JOINT ADVANCED MISSILE INSTRUMENTATION PROJECT HIGH DYNAMIC GPS- WE FINALLY GOT IT

Powell, Dave, Scofield, Don 10 1900 (has links)
International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California / Joint Advanced Missile Instrumentation (JAMI), a Central Test and Evaluation Investment Program (CTEIP) initiative, is developing advanced telemetry system components that can be used in an integrated instrumentation package for tri-service small missile test and training applications. JAMI demonstrated significant improvement in the performance of low-cost Global Positioning System (GPS) based Time-Space-Position Information (TSPI) tracking hardware that can be used for world-wide test and training. Acquisition times of less than 3 seconds from a cold start and tracking dynamics to over 60 Gs were demonstrated. The design of a programmable Flight Termination Safe and Arm device has been completed. This paper discusses the progress of the program during the past year and the efforts planned for fiscal year 2002. High dynamic testing results of GPS and Inertial measurement Unit (IMU) devices and problems encountered are discussed.
27

A STATUS REPORT OF THE JOINT ADVANCED MISSILE INSTRUMENTATION PROGRAM AN OFFICE OF THE SECRETARY OF DEFENSE CENTRAL TEST AND EVALUATION INVESTMENT PROGRAM INITIATIVE

Powell, Dave, Scofield, Don 10 1900 (has links)
International Telemetering Conference Proceedings / October 22-25, 2001 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Joint Advanced Missile Instrumentation (JAMI), a Central Test and Evaluation Investment Program (CTEIP) initiative, is developing advanced telemetry system components that can be used in an integrated instrumentation package for tri-service small missile test and training applications. JAMI has made significant progress in the development of Global Positioning System (GPS) based Time-Space- Position Information (TSPI) tracking hardware, flight termination equipment and end-game vector scoring technology in low cost, modular packages that will allow world-wide test and training. The JAMI program is in full-scale development of advanced GPS technologies to reduce the cold start Time- To-First-Fix (TTFF) to less than 3 seconds. This paper discusses the progress of the program during the past year and the efforts planned for fiscal year 2001. Testing results of GPS receivers to levels of over 50 Gs and problems encountered in programming GPS simulator for missile flight profiles are discussed.
28

Utveckling av GIS-applikation för effektivisering av planeringsarbeten för infrastruktur

Andersson, Fredrik January 2015 (has links)
Planeringsarbeten för infrastruktur sker ofta med hjälp av speciella programvaror som CAD för att skapa ritningar på kartor över områden där tänkta infrastrukturer skall utvecklas. Som en effektivisering för dessa arbeten handlar denna studie om implementering av en GIS-applikation för att motivera fördelar med GIS och sättet för hantering samt visualisering av geografisk information. En webbapplikation som hanterar baskartor samt överliggande vektorlager för infrastruktur utvecklas, samt även att samma kartdata över infrastrukturen kopplas till en mobilapplikation för att effektivisera eventuella inventeringsarbeten av infrastrukur med hjälp av GPS för att kunna positionera infrastruktur på ett bra sätt. Tekniken bakom utvecklingen bygger på HTML, CSS och JavaScript samt molntjänstlagrin av infrastruktursdata i en geodatabas . GIS-applikationen sammanställer svar på frågor som bevisar hur GIS på ett tillfredställande sätt mycket väl skulle kunna implementeras och användas praktiskt i ett utvecklingsarbete för infrastruktur i dagens morderna samhälle.
29

Variation in prescribing in general practice

Carthy, Patricia Ann January 2000 (has links)
No description available.
30

Evaluation of Welsh drug information services

Adams, Paul Richard January 1992 (has links)
No description available.

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