Improved Geo-Spatial Resolution Using a Modified Approach to the Complex Ambiguity Function (CAF)

Abstract : The purpose of this thesis is to implement the CAF-Map method of geolocation in MATLAB. This method is a modification to the traditional Cross Ambiguity Function (CAF) based TDOA, FDOA geolocation where TDOA and FDOA are determined by locating the peak in the CAF plane and then the peak's information is fed to a Least Squares like geolocation tool to determine the emitters geolocation. This method omits the step in which the geolocation is determined with the "post processed" CAF peak information and instead maps the CAF surface directly to the earth's surface. In this thesis, the traditional CAF based geolocation is explained and the limitations are discussed. After this, the development of the CAF-Map method is explained and the algorithm is presented. This thesis explores the use of the CAF-Map method as a geolocation alternative to the traditional TDOA, FDOA methods and demonstrates its ability to geolocate co-channel emitters.

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