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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.
151

GPS HIGH DYNAMIC RECEIVER TRACKING DEMONSTRATION RESULTS

Hurd, William J., Statman, Joseph I., Vilnrotter, Victor A. 10 1900 (has links)
International Telemetering Conference Proceedings / October 28-31, 1985 / Riviera Hotel, Las Vegas, Nevada / Demonstration results are presented for a high dynamic GPS receiver. The receiver tested is a breadboard unit capable of tracking one simulated satellite signal in pseudorange and range rate. The receiver makes approximate maximum likelihood estimates of pseudorange and range rate each 20 ms, and tracks these observables using a third order filter with a time constant of 0.14 s. Carrier phase is not tracked, which eliminates the typical failure mode of loss of carrier lock associated with PLLs at high dynamics. The receiver tracks with pseudorange lag errors of under 0.06 m when subjected to simulated 50 g turns with 40 g/s peak jerk. Pseudorange errors due to receiver noise alone are approximately 0.6 m rms at a carrier power to noise spectral density ratio of 34 dB-Hz. The tracking threshold SNR is approximately 28 dB-Hz, which provides 12 dB margin relative to the 40 dB-Hz that occurs with minimum specified satellite signal strength, 3.5 dB system noise figure, and 0 dBi antenna gain.
152

HIGH DYNAMIC GPS UNAIDED PSEUDORANGE TRACKING DEMONSTRATION

Hurd, William J., Statman, Joseph I. 10 1900 (has links)
International Telemetering Conference Proceedings / October 22-25, 1984 / Riviera Hotel, Las Vegas, Nevada / A breadboard high dynamic GPS receiver capable of pseudorange tracking with accelerations of 50 g or higher without inertial aiding is presented. The receiver uses cross correlation followed by fast Fourier transformation to approximate maximum likelihood estimation of pseudorange and range rate, with no phase or delay locked loops. The breadboard system consists of a one channel receiver and a high dynamics signal simulator. A planned demonstration of the receiver is described and anticipated results are presented showing pseudorange lag errors of under 10 m with acceleration of 50 g.
153

Distributed Interactive Simulation: The Answer to Interoperable Test and Training Instrumentation

Kassan, Mark W. 10 1900 (has links)
International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / This paper discusses Global Positioning System (GPS) Range Applications Joint Program Office (RAJPO) efforts to foster interoperability between airborne instrumentation, virtual simulators, and constructive simulations using Distributed Interactive Simulation (DIS). In the past, the testing and training communities developed separate airborne instrumentation systems primarily because available technology couldn't encompass both communities' requirements. As budgets get smaller, as requirements merge, and as technology advances, the separate systems can be used interoperably and possibly merged to meet common requirements. Using DIS to bridge the gap between the RAJPO test instrumentation system and the Air Combat Maneuvering Instrumentation (ACMI) training systems provides a defacto system-level interoperable interface while giving both communities the added benefits of interaction with the modeling and simulation world. The RAJPO leads the test community in using DIS. RAJPO instrumentation has already supported training exercises such as Roving Sands 95, Warfighter 95, and Combat Synthetic Test, Training, and Assessment Range (STTAR) and major tests such as the Joint Advanced Distributed Simulation (JADS) Joint Test and Evaluation (JT&E) program. Future efforts may include support of Warrior Flag 97 and upgrading the Nellis No-Drop Bomb Scoring Ranges. These exercises, combining the use of DIS and RAJPO instrumentation to date, demonstrate how a single airborne system can be used successfully to support both test and training requirements. The Air Combat Training System (ACTS) Program plans to build interoperability through DIS into existing and future ACMI systems. The RAJPO is committed to fostering interoperable airborne instrumentation systems as well as interfaces to virtual and constructive systems in the modeling and simulation world. This interoperability will provide a highly realistic combat training and test synthetic environment enhancing the military's ability to train its warfighters and test its advanced weapon systems.
154

THE APPLICATION OF MAP MATCHING METHOD IN GPS/INS INTEGRATED NAVIGATION SYSTEM

Fei, Peng, Qishan, Zhang, Zhongkan, Liu 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / Map matching method plays an important role in vehicle location and navigation systems. It employs the information in a digital map to compensate the positioning error. This paper presents a fuzzy-logic-based probabilistic map-matching algorithm used in GPS/INS integrated navigation systems, in which the reliability degree of map matching resolution is given explicitly as the decision basis in selecting matching road segment by utilizing the fuzzy comprehensive judgement. The results of experimental simulations have shown that the system performance gained significant enhancement by introducing this algorithm.
155

GPS RECEIVER SELECTION AND TESTING FOR LAUNCH AND ORBITAL VEHICLES

Schrock, Ken, Freestone, Todd, Bell, Leon 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / NASA Marshall Space Flight Center’s Bantam Robust Guidance Navigation & Control Project is investigating off the shelf navigation sensors that may be inexpensively combined into Kalman filters specifically tuned for launch and orbital vehicles. For this purpose, Marshall has purchased several GPS receivers and is evaluating them for these applications. The paper will discuss the receiver selection criteria and the test equipment used for evaluation. An overview of the analysis will be presented including the evaluation used to determine their success or failure. It will conclude with goals of the program and a recommendation for all GPS users.
156

COMBINING GPS AND PACKETIZED TELEMETRY CONCEPTS TO FORM A WIDE AREA DATA MULTIPLEX SYSTEM

Grebe, David L. 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / As testing requirements on the ranges require ever more sophisticated cross correlation of data from multiple data acquisition sources, it becomes increasingly advantageous to collect and disseminate this information in a more network oriented fashion. This allows any of the data collected at physically separated sites to be used simultaneously at multiple mission control or data reduction centers. This paper presents an approach that maximizes the use of legacy communication paths and data reduction systems to support an evolutionary migration toward the day when testing can take full advantage of commercial communication protocols and equipment such as OC-3, ATM, etc. One key element of this approach is the packetizing of data at each reception point to provide virtual circuit switching using packet routing. Based on the newly adopted IRIG/RCC 107-98 standard, the system may even be expanded all the way back to the actual sensors. The second key element is the use of the readily available time and timing pulses based on GPS to establish a uniform sampling interval that will allow the cross correlation of data received at different points spread over a wide area.
157

STUDY ON OEM-BASED DIFFERENTIAL GPS

Shengxi, Ding, Qishan, Zhang, Xianliang, Li 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Two kinds of differential GPS (DGPS) technology on position differential GPS and pseudo-range differential GPS are studied and compared in this paper. Positioning tests by single GPS receiver, position DGPS and pseudo-range DGPS systems based on GPSOEM board are done. Experiment result indicates that position error is about 30 - 100 meters on single GPS receiver and position error is reduced to 3 - 10 meters on DGPS. Furthermore, Developed DGPS system which is based on GPS-OEM has the advantages of low cost, utility and flexibility, etc.
158

VEHICLE MONITORING SYSTEM FOR PUBLIC TRAFFIC IN BEIJING

Dongkai, Yang, Xin, Bai, Qishan, Zhang 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / With the rapid development of urban economy, there are bus increasing, route extending, and shuttle frequency increasing etc. At the same time, road construction is subject to land surface, so traffic jam often occurs. It is a big trouble for life of citizens and problem for economy development. So it needs to be improved as fast as possible. Vehicle monitoring system for public traffic in Beijing can expediently monitor the state of each controlled bus, thereby making perfect management. With the integration of GPS, analog trunked communication and digital map, the old, blinding manage system of public traffic would be changed into advanced, visualized management mode, and several routes are dispatched in one dispatch center at the same time. The system frame and its components are introduced in this paper.
159

KEY TECHNOLOGIES IN DEVISING AUTONOMOUS VEHICLE LOCATION AND NAVIGATION SYSTEM

Fei, Peng, Pingfang, Zheng, Qishan, Zhang, Zhongkan, Liu 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / In this paper, a devising scheme of Autonomous Vehicle Location and Navigation System is introduced firstly. Then, several key technologies used in the devising scheme are presented, which includes a data fusion method based on extended decentralized kalman filter technology, a map-matching method used to compensate the positioning error, and a digital map data processing method used to realize route planning algorithm. By this time, a sample machine based on the devising scheme introduced in this paper has already been worked out successfully. The availability and the advantages of these technologies have been demonstrated.
160

DESIGN AND REALIZATION OF DELAY MAPPING RECEIVER BASED ON GPS FOR SEA SURFACE WIND MEASUREMENT

Ronglei, Hu, Dongkai, Yang, Qishan, Zhang, Yiqiang, Zhang 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 Delay Mapping Receiver (DMR) is used for receiving and processing the reflected GPS signal to get the information of sea surface wind by recording and matching the data with the theoretical model. The hardware architecture and software design are described in detail in this paper. The test results at near sea of Tianjin of China are provided, which prove that the design of DMR is successful and the collected data are useful for the sea surface wind measurement.

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