Date of Award


Document Type


Degree Name

Master of Science in Electrical Engineering


Department of Electrical and Computer Engineering

First Advisor

Robert N. Riggins, PhD


In order to quantify the performance and accuracy of existing navigation systems, the U.S. Air Force has been using the Completely Integrated Reference Instrumentation System (CIRIS) as a baseline. CIRIS combines information from an inertial navigation unit, a barometric altimeter, and a range/range-rate system of ground transponders to obtain a navigation solution. This research explores the possibilities of enhancing CIRIS by adding measurements obtained from the Global Position System (GPS). Pure pseudorange measurement updates to the CIRIS Extended Kalman Filter form the basis of the Navigation Reference System (NRS). Applying differential corrections to the pseudorange measurements forms the basis of the Enhanced Navigation Reference System (ENRS). The addition of Carrier-Phase GPS measurements to the ENRS forms the basis of the Precision Navigation Reference System (PNRS). Analysis of these three systems is performed using a software package known as Multimode Simulation for Optimal Filter Evaluation (MSOFE). The performance of the three filters are compared as well as the PNRS's performance when subjected to cycle slips. Results of the simulations indicate that the PNRS can provide an improved navigation solution over CIRIS, the NRS, and the ENRS and the filter is stable for large cycle slips and small cycle slips are negligible.

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DTIC Accession Number



The author's Vita page is omitted.