ECM RESISTANT GLOBAL POSITIONING SYSTEM (GPS) RECEIVER

GPS IS PLANNED TO BE USED BY THE U.S. ARMY IN A VARIETY OF TACTICAL SCENARIOS. FIRE CONTROL APPLICATIONS ARE CURRENTLY BEING INVESTIGATED WHERE GPS WOULD BE USED TO TRACK REGISTRATION ROUNDS AND LOCATE RADIOSONDES. SINCE GPS IS A RADIONAVIGATION SYSTEM, ITS EFFECTIVENESS IN A TACTICAL ENVIRONMENT IS LIMITED BY ITS SUSCEPTIBILITY TO ELECTRONIC COUNTERMEASURES (ECM). IT IS PARTICULARLY DIFFICULT TO TRACK A HIGH-DYNAMIC PLATFORM, SUCH AS A REGISTRATION ROUND OR FIGHTER AIRCRAFT, IN THE PRESENCE OF A JAMMER DUE TO THE LARGE SIGNAL PROCESSING BANDWIDTH REQUIRED TO ACCOMMODATE THE SIGNAL DOPPLER SHIFT. THIS PROPOSAL DESCRIBE THE DEVELOPMENT OF DIGITAL SIGNAL PROCESSING (DSP) ALGORITHMS THAT WILL ENHANCE THE ECM RESISTANCE OF A TACTICAL GPS RECEIVER. AN INNOVATIVE "SOFTWARE" RECEIVER ARCHITECTURE IS DESCRIBED THAT WILL BE USED TO IMPLEMENT THESE ALGORITHMS IN PHASE II. THE SOFTWARE RECEIVER TAKES ADVANTAGE OF THE DEVELOPMENT OF HIGH-SPEED DSP MICROPROCESSORS WHICH ARE CAPABLE OF PERFORMING REAL-TIME CODE AND CARRIER TRACKING ON THE 20 MHZ SAMPLED P-CODE SIGNALS. THIS APPROACH WILL ALLOW MAXIMUM FLEXIBILITY IN DEVELOPING A PROOF-OF-CONCEPT ECM RESISTANT RECEIVER UNDER PHASE II AS WELL AS PROVIDING A VIABLE RECEIVER DESIGN FOR FUTURE PRODUCTION. THE ECM RESISTANT RECEIVER WILL BE CAPABLE OF TRACKING HIGH-DYNAMIC PLATFORMS UNDER HIGH JAMMING CONDITIONS. THE RECEIVER WILL ALSO BE SUITABLE FOR INTEGRATION INTO A TRANSLATOR PROCESSING SYSTEM FOR TRACKING GPS TRANSLATOR ON REGISTRATION ROUNDS.