Step Continuous Wave Synthetic Aperture Radar Experiment System Design

Synthetic Aperture Radar (SAR) is a type of radar imaging system that radar moves while imaged target keeps still. Small aperture antenna is used in SAR system to transmit and receive wide-band microwave signal, large antenna aperture is synthesized by spatial diversity, and high range and cross-range resolution can be achieved. As active radar, SAR can work under all weather and in all time, and will not be affected by the illumination and the weather. It can also detect the target penetrating through the earth's surface and vegetation.Supported by a project of "2110" laboratory construction, this thesis is focused on the study of ground-based SAR system and its application. The main contributions are as follows,(1) A set of synthetic aperture microwave imaging system is designed and implemented in X band. The high range resolution is achieved by using stepped frequency continuous wave, while the high azimuth resolution is formed by spatial diversity.(2) The system software on host computer in the SAR system is accomplished. The object-oriented programming theory is applied to solve the problem of complex mapping process from analysis and designing to software modules, so that the flexibility and reuse of the software is greatly enhanced. MFC is used to provide a friendly interactive interface. The mixed programming technique between C + + and Matlab is used, so that the imaging results can be displayed in a familiar way. Some other advanced programming techniques are applied to make the software more user-friendly and more flexible.(3) Test and measurement of the designed SAR system are accomplished. The measured results validate the correction of the designed software and hardware. The range and cross range resolution of the system is better than 0.3 meters * 0.3 meters for the targets 50 meters away.