Date of Award


Document Type


Degree Name

Master of Science


Department of Electrical and Computer Engineering

First Advisor

Robert N. Riggins, PhD


An Inertial Navigation System (INS), the Global Positioning System (GPS), and a ground based transponder system (RRS) can all be used to provide the user with a navigation solution. Yet by integrating these three navigation systems with an extended Kalman filter (EKF), a navigation solution is attained that benefits from the information of all three subsystems. This research develops a multiple model EKF failure detection, isolation, and recovery (FDIR) algorithm using a Chi-Square failure test to provide robust navigation solution to measurement failures. The algorithm specifically counters failures in the GPS and RRS range measurements. Analysis is conducted using a Kalman filter development package known as the Multimode Simulation for Optimal Filter Evaluation (MSOFE). Both a large order truth model for the navigation system (in which a full 24 satellite constellations is modeled) and a reduced- order Kalman filter are developed. Results suggest that the multiple model algorithm can correct for all single measurement failures.

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The author's Vita page is omitted.