ADVANCED ANTENNA WINDOW TECHNOLOGY, SNYTHETIC-APERTURE-RADAR REENTRY APPLICATIONS

THE USE OF SYNTHETIC-APERTURE-RADAR (SAR) SENSORS TO AID IN NAVIGATION ON THE NEW HIGH PERFORMANCE MANEUVERING LIFTING REENTRY VEHICLES (HP-MARV) DURING THE LONG LEVEL GLIDE PORTION OF THE TRAJECTORY HAS GOOD POTENTIAL. SAR SENSORS ARE AN INTERESTING ALTERNATIVE TO THE HIGH POWER SCANNED PENCIL BEAM TERMINAL FIX SENSORS OF THE PAST BECAUSE THE ANTENNA SUB-SYSTEM IS TYPICALLY A FIXED NON-SCANNED SIDE LOOKING ARRAY WHICH IS MORE EASILY IMPLEMENTED, AND THE AVERAGE TRANSIT POWER IS LOW. THE LIMITING FACTORS OF SAR SENSORS ARE COMPUTER RESOURCES AND LONG TIME COHERENT SIGNAL COLLECTION AND PROCESSING. THIS PROPOSED STUDY WILL INVESTIGATE THE VARIOUS ASPECTS OF APPLYING SAR TECHNOLOGY TO THE NEW HIGH PERFORMANCE MANEUVERING REENTRY VEHICLES SUCH AS HP-MARV. THE PHASE I RESEARCH WILL DETERMINE SAR FEASIBILITY, PERFORMANCE, AND TRADE-OFFS INCLUDING THE EFFECTS OF TRAJECTORY, AEROTHERMAL HEATING/ABLATION, PLASMA SHEATHING, UNCERTAINTIES IN MOTION COMPENSATION, SENSOR FREQUENCY, PRF, TRANSMITTER POWER, SAR SIGNAL PROCESSING, SAR IMAGE RESOLUTION, ANTENNA SIZE, AND ANTENNA WINDOW CONFIGURATION. IN ADDITION, THE STUDY WILL DEMONSTRATE ALL OF THE MODELING CAPABILITIES, DETERMINE THE SOFTWARE ARCHITECTURE, AND SOFTWARE SPECIFICATIONS TO COUPLE THE SAR ANALYSIS INTO AN END-TO-END REENTRY 6DOF SENSOR SIMULATION. THE RESULTS FROM THIS STUDY WOULD PROVIDE VALUABLE DATA AND ANALYSIS TOOLS TO VARIOUS DOD AGENCIES TO EVALUATE ADVANCED MANEUVERING HYPERSONIC VEHICLE CONCEPTS WITH RADAR SENSORS SUCH AS MARV, HP-MARV, AND NATIONAL-AERO-SPACE PLANS.