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Generalized Residual Multiple Model Adaptive Estimation Of Parameters And States, Charles D. Ormsby
Generalized Residual Multiple Model Adaptive Estimation Of Parameters And States, Charles D. Ormsby
Theses and Dissertations
This dissertation develops a modification to the standard Multiple Model Adaptive Estimator (MMAE) which allows the use of a new "generalized residual" in the hypothesis conditional probability calculation. The generalized residual is a linear combination of traditional Kalman filter residuals and "post-fit" Kalman filter residuals which are calculated after measurement incorporation. This modified MMAE is termed a Generalized Residual Multiple Model Adaptive Estimator (GRMMAE). The dissertation provides a derivation of the hypothesis conditional probability formula which the GRMMAE uses to calculate probabilities that each elemental filter in the GRMMAE contains the correct parameter value. Through appropriate choice of a single …
Development And Simulation Of A Pseudolite-Based Flight Reference System, Terry J. Bouska
Development And Simulation Of A Pseudolite-Based Flight Reference System, Terry J. Bouska
Theses and Dissertations
Current flight reference systems are vulnerable to GPS jamming and also lack the accuracy required to test new systems. Pseudolites can augment flight reference systems by improving accuracy, especially in the presence of GPS jamming. This thesis evaluates a pseudolite-based flight reference system which applies and adapts carrier-phase differential GPS techniques. The algorithm developed in this thesis utilizes an extended Kalman filter along with carrier-phase ambiguity resolution techniques. A simulation of the pseudolite-based positioning system realistically models measurement noise, multipath, pseudolite position errors, and tropospheric delay. A comparative evaluation of the algorithms performance for single and widelane frequency measurements is …
Tightly-Coupled Image-Aided Inertial Navigation System Via A Kalman Filter, Michael G. Giebner
Tightly-Coupled Image-Aided Inertial Navigation System Via A Kalman Filter, Michael G. Giebner
Theses and Dissertations
Inertial navigation systems and GPS systems have revolutionized the world of navigation. Inertial systems are incapable of being jammed and are the backbone of most navigation systems. GPS is highly accurate over long periods of time, and it is an excellent aid to inertial navigation systems. However, as a military force we must be prepared to deal with the denial of the GPS signal. This thesis seeks to determine it, via simulation, it is viable to aid an INS with visual measurements.
Ins Aiding Using Passive, Bearings-Only Measurements Of An Unknown Stationary Ground Object, Alec E. Porter
Ins Aiding Using Passive, Bearings-Only Measurements Of An Unknown Stationary Ground Object, Alec E. Porter
Theses and Dissertations
The theory for Inertial Navigation System (INS) aiding using passive, bearings only measurements of an unknown stationary ground object, in the vein of optical flow measurement, is developed. Stand-alone bearings-only measurements over time of an unknown, but stationary, ground object are shown to yield estimates of the aircraft’s aerodynamic angles, viz., the angle of attack and sideslip angle. Two new equations containing the aircraft’s angular navigation variables ψ, θ, φ, γ, H, and the aerodynamic angles are derived. This allows an update of the aircraft’s attitude, thus making INS aiding using passive, bearings-only measurements possible. Moreover, the use of stadiametry, …
A Three-Dimensional Heads-Up Primary Navigation Reference Display For Paratroopers Performing High Altitude High Open Jumps, Brian A. Balazs
A Three-Dimensional Heads-Up Primary Navigation Reference Display For Paratroopers Performing High Altitude High Open Jumps, Brian A. Balazs
Theses and Dissertations
The Department of Defense (DoD) relies on the para-dropping of resources to meet different objectives in order to accomplish missions during peace-time, war-time, or military operations other than war. The resources dropped to the ground via parachute range from supplies and equipment to the most valued asset, people. Tactics have been developed to increase the safety of troops parachuting into areas of conflict. These tactics include high-altitude high-opening (HAHO) jumping and night jumping. HAHO jumping allows paratroopers to travel large distances in the air away from the path of the delivering aircraft. While night jumping, done with the aid of …
The Effects Of Gps M-Code On Radar Detection, Jae K. Yang
The Effects Of Gps M-Code On Radar Detection, Jae K. Yang
Theses and Dissertations
The GPS system is undergoing a modernization effort which will add several new signals to be placed at the L1, L2, and L5 frequency bands. One of the signals to be placed on L2 is a new military code (M-code) which may be transmitted at a higher power level than current GPS signals. Other users of the L2 frequency band are concerned with the potential interference that may be caused by the increase in power of the GPS signal. One particular use of the 1215-1400 MHz frequency band is Air Traffic Control (ATC) radar applications.