LINEAR-SAR VERSES CIRCULAR-SAR FOR FLIGHT-LINE RCS MEASUREMENTS

摘要

Over the past few years several flight-line RCS measurement systems have been developed. Some of these systems use a linear rail to collect aspect angle data and other systems use no rails or "free-path" circular collections. A comparison of these two different collection methods have never been publicly presented.rnIn this paper, a discussion of the differences between the Linear-SAR and Circular-SAR collection methodologies will be presented. Specifically, issues associated with field quality, nearfieid effects, and processing requirements will be covered in the discussion. Linear-SAR has the advantage of being more easily controlled and therefore not requiring motion compensation. Linear-SAR systems generally do not have mechanisms to point the antenna toward the target, thus limiting the angle extent of the collection aperture. In contrast, the Circular-SAR can theoretically collect data 360 degrees around the target at a constant range. However, the free-path Circular-SAR requires some form of motion compensation of the data for image formation processing.