Research On Azimuth Digital Superresolution Based On Synthetic Aperture Radar

Being able to work around the clock is a unique advantage of radar remote sensing compared to other remote sensing systems.On this basis,synthetic aperture radar can also have better multi-dimensional resolution and obtain more information.It has a wide range of needs and applications in military fields such as reconnaissance,detection,monitoring,and disaster warning,geological exploration,surveying,and mapping,as well as in civil scenarios such as agriculture.With the continuous deepening of applications,the problems and challenges faced continue to increase.One of them is the need to obtain higher resolution images.However,traditional methods that simply and directly improve resolution through hardware and physical means cannot meet the resolution requirements under various conditions.Therefore,the research on super resolution has been proposed,and improvements in software level of data processing can effectively solve this problem.It is also an important component of the research on improving SAR resolution.Currently,there are various focuses and inconclusive conclusions on the research of super resolution imaging.The following studies have been conducted in this article,mainly including:(1)Aiming at the theoretical resolution limitations of current SAR imaging,a super resolution optimization method based on frequency domain imaging algorithms is proposed,which can be applied to most SAR imaging scenarios,maintaining high imaging efficiency,while obtaining images with better accuracy and theoretical resolution.(2)Considering the problems and limitations of the application of hyperoscillation theory in the imaging field,by reviewing and summarizing relevant research content,analyzing the focusing models and the focusing process of SAR echo signals in existing studies,a more suitable hyperoscillation optimization method for SAR imaging was selected,and the optimization method was applied to the focusing model of SAR.A set of optimization parameters that can achieve superresolution imaging were derived and solved.(3)The super resolution design method based on super oscillation is applied to focus the echo signal,forming a SAR super resolution imaging algorithm based on super oscillation optimization.The feasibility and correctness of the algorithm are verified through point target simulation,and the simulation results are compared with those of existing frequency domain imaging algorithms.The applicability of the algorithm was verified through open source real image data,and the effectiveness and shortcomings of the optimization methods in this article were analyzed.