Date of Award


Document Type


Degree Name

Master of Science in Electrical Engineering


Department of Electrical and Computer Engineering

First Advisor

Robert Riggins, PhD


An extended Kalman filter (EKF) is used to combine the information obtained from a Global Positioning System (GPS) receiver and an Inertial Navigation System (INS) to provide a navigation solution. This research compares the results of an actual tightly-coupled GPS-INS integrated system with those obtained in computer simulation. Differences between the simulation and actual hardware results, such as navigation solutions and tuning values, are shown in the research. An analysis of various GPS models was studied to determine the best representation for a system truth model. Measurement updates and their effects upon position accuracies was considered and preliminary research was conducted to determine when a feedback implementation was advantageous over a feedforward approach. The results suggest that the computer simulations being used at the Air Force Institute of Technology (AFIT) produce better navigation solutions than are actually possible with real hardware. Alternate system truth models were found which would estimate the errors of an actual system more accurately with less computational loading.

AFIT Designator


DTIC Accession Number



The author's Vita page is omitted.