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Full-Text Articles in Engineering
Real-Time Gps-Alternative Navigation Using Commodity Hardware, Jordon L. Fletcher
Real-Time Gps-Alternative Navigation Using Commodity Hardware, Jordon L. Fletcher
Theses and Dissertations
Modern navigation systems can use the Global Positioning System (GPS) to accurately determine position with precision in some cases bordering on millimeters. Unfortunately, GPS technology is susceptible to jamming, interception, and unavailability indoors or underground. There are several navigation techniques that can be used to navigate during times of GPS unavailability, but there are very few that result in GPS-level precision. One method of achieving high precision navigation without GPS is to fuse data obtained from multiple sensors. This thesis explores the fusion of imaging and inertial sensors and implements them in a real-time system that mimics human navigation. In …
Use Of Two-Way Time Transfer Measurements To Improve Geostationary Satellite Navigation, Benjamin G. Dainty
Use Of Two-Way Time Transfer Measurements To Improve Geostationary Satellite Navigation, Benjamin G. Dainty
Theses and Dissertations
An emerging use of GPS is to provide accurate navigation information for satellites in orbit. The GPS satellites are designed to provide service to terrestrial users, so the antenna array points directly towards the Earth and uses a narrow primary beamwidth. Because GEO altitudes are well above the GPS constellation, the Earth occludes most of the GPS signals to the satellite. Decreased satellite visibility is debilitating, as GPS navigation requires at least four visible satellites to determine position. To assist with the visibility problem, the receiver can look at the GPS satellite transmit antenna side lobes, but this does not …