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Fusion Of Imaging And Inertial Sensors For Navigation, Michael J. Veth
Fusion Of Imaging And Inertial Sensors For Navigation, Michael J. Veth
Theses and Dissertations
The motivation of this research is to address the limitations of satellite-based navigation by fusing imaging and inertial systems. The research begins by rigorously describing the imaging and navigation problem and developing practical models of the sensors, then presenting a transformation technique to detect features within an image. Given a set of features, a statistical feature projection technique is developed which utilizes inertial measurements to predict vectors in the feature space between images. This coupling of the imaging and inertial sensors at a deep level is then used to aid the statistical feature matching function. The feature matches and inertial …
Characterizing The Impact Of Precision Time And Range Measurements From Two-Way Time Transfer Systems On Network Differential Gps Position Solutions, Kendra L. B. Cook
Characterizing The Impact Of Precision Time And Range Measurements From Two-Way Time Transfer Systems On Network Differential Gps Position Solutions, Kendra L. B. Cook
Theses and Dissertations
Precise positioning plays an important role for both military and civilian users, from cell phones and OnStar to precision munitions and swarms of UAVs. Many applications require precise relative positioning of a network of vehicles (such as aircraft, tanks, troops, etc). Currently, the primary means for performing precise positioning is by using the Global Positioning System (GPS), and although GPS has become commonplace in today’s society, there are still limitations affecting the system. Recent advances in dynamic Two-Way Time Transfer (TWTT) have potentially provided a means to improve precise relative positioning accuracy over differential GPS (DGPS)-only approaches. TWTT is a …
A Climatological Study Of Equatorial Gps Data And The Effects On Ionospheric Scintillation, Katharine A. Wicker
A Climatological Study Of Equatorial Gps Data And The Effects On Ionospheric Scintillation, Katharine A. Wicker
Theses and Dissertations
Ionospheric scintillation is detrimental to radio signals, especially those from the global positioning system. Such scintillation is caused when a signal permeates the ionosphere through plasma bubbles. The signal’s phase and amplitude can be altered, and a receiver on the ground can lose lock on the GPS signal. Measured using a zero to one index known as S4, scintillation severity is based upon season, solar cycle, time of day, location and frequency. The most severe scintillation occurs at the equatorial anomaly, or fifteen degrees north and south of the equator. Seven years of data from fifteen different locations around the …