Abstract: The operation and processing for an azimuth scan mode patch-mapping synthetic aperture radar (SAR) system are studied, which serves for moderate fine-resolution mapping of medium-sized terrain patches. First, the geometry of the scan mode is depicted, and the scan angular velocity and scan angular scope are determined according to the desired imagery patch size and cross-range resolution respectively. Then, the geometric relation between the mapped area and the flight path of the antenna is determined. The signal processing approaches are discussed in the following. The linear range Doppler and polar format algorithms are employed in image formation, and simulation is conducted to get the point target response. Finally, the experimental result of the test campaign with the described system is also presented to verify the proposed scheme.

Key words: synthetic aperture radar (SAR), beam scan, patch-mapping, scan angular velocity, scan angular scope