Study On Key Techniques Of SAR-GMTI For Airborne Radar

Synthetic Aperture Radar (SAR) imaging and Moving Target Indicating (MTI) are hot topics in radar research and application with the development of digital micro electronics. The combination of synthetic aperture imaging and MTI technologies can provide ground real time information in a clear, correct and direct way and will be widely used for sea monitoring, geologic disasters and civil area. Synthetic aperture imaging and MTI have been successfully used in military battlefield surveillance and acquisition of enemy military information. Unfortunately, wide gap on the above technologies still exists between china and America or other western countries, that's why airborne synthetic aperture radar (SAR) and ground moving target indicating (GMTI) technology is selected for study in this paper.Synthetic aperture imaging technology is introduced above all with emphases on Range Doppler Algorithm (RDA) and Polar Format Algorithm (PFA),which are main imaging algorithms in SAR-GMTI. Range migration, rotation compensation, front wave curve correction and interpolation technologies are analyzed in details. Simulation and real data demonstration are done for these two classical algorithms, which are mainly used for SAR-GMTI both in China and oversea.Three typical approaches for multi-channel ground moving target indication are presented afterward in the paper: Displaced Phase Center Antenna (DPCA), Along-Track Interferometry (ATI) and Space-Time Adaptive Processing (STAP). Feasibility of these approaches has been demonstrated with computer simulation. Three-channel ATI technology has been researched for project application, and its effeteness has been validated with real recordeded data.At last, This has been pointed out , which STAP is a important direction of study on SAR-GMTI.