COMPARING TIME - BASED AND HYBRID TIME - BASED / FREQUENCY BASED MULTI - PLATFORM GEO - LOCATION SYSTEMS Andrew

THESIS Approved for public release; distribution is unlimited. While time difference of arrival (TDOA) information is sufficient to passively solve for the location of a radio frequency transmitter, frequency difference of arrival (FDOA) information may be added to the TDOA information to solve for both the position and velocity of the transmitter. This analysis implements a stochastic discrete event simulation, written in Java, to compare and stochastically describe, under a variety of conditions, the differences between a mixed TDOA/FDOA Multi-platform Global Positioning System (GPS) Assisted Geo-location System and that of the same system which uses TDOA information only. The presented analysis compares both solution types for two-and three-dimensional fixes across: various measurement error distributions and correlation values, sensor network geometry, and sensor platform selection. The simulation results show first order stochastic dominance in the accuracy of the TDOA/FDOA solution in the two-dimensional scenarios. In the three-dimensional scenarios, sensor network to target geometry dominates both solutions' accuracy. While solution accuracy is used as the primary method of effectiveness, the distribution of each solution's uncertainty is also compared. Finally, the simulation itself remains a useful tool for further system design experimentation, performance indication, and as a means to describe system capabilities to the war fighter. Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instruction, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden, to Washington headquarters The views expressed in this thesis are those of the author and do not reflect the official policy or position of the Department of Defense or the U.S. Government. 13. ABSTRACT (maximum 200 words) While time difference of arrival (TDOA) information is sufficient to passively solve for the location of a radio frequency transmitter, frequency difference of arrival (FDOA) information may be added to the TDOA information to solve for both the position and velocity of the transmitter. This analysis implements a stochastic discrete event simulation, written in Java, to compare and stochastically describe, under a variety of conditions, the differences between a mixed TDOA/FDOA Multi-platform Global Positioning System (GPS) Assisted Geo-location System and that of the same system which uses TDOA information only. The presented analysis compares both solution types for two-and …