Global positioning system processing methods for GPS passive coherent location

Abstract

This study addresses processing methods for the use of the global positioning system (GPS) as a signal of opportunity in a multistatic passive coherent location (PCL) system. The signal properties of the GPS signal are designed for position estimation, which makes it particularly suited for GPS PCL applications. The signal specifications are examined and the potential limitations of a proposed system are explored. Conventional GPS processing techniques are implemented in the framework of multistatic GPS PCL. GPS specific methods are developed for target position estimation of a multistatic PCL system in a three‐dimensional plane. The PCL system has comparable performance metrics to conventional GPS positioning. Two methods are developed utilising measurements available in a conventional GPS system. The first involves a short time scale, which is in the order of milliseconds. The second involves a long time scale method, which is on the order of seconds. Simulation and analysis are performed to verify the methods. Experimental validation was also conducted using a hardware in the loop approach, as well as, an active radar calibrator.