Microwave motion induced synthetic aperture radiometer using sparse array

Abstract

Several studies have been performed on microwave aperture synthesis carried out from a moving platform, in order to achieve high spatial resolution with a small number of antennas. In this paper, the limitations of previous developed Motion Induced Synthetic Aperture Radiometer systems are discussed, and an improved observation model, imaging method, and antenna array configuration are presented. An observation model and an imaging method suitable for imaging extended sources are developed, which is a more practical consideration than a point source. It is found that the antenna array configuration used in previous studies causes significant degradation of imaging performance. To improve this, the use of a sparse array is proposed. The sparse T‐shaped array is designed and discussed based on the analysis of spatial frequency coverage. The proposed sparse T‐shaped array can cover a spatial frequency plane efficiently, resulting in a better imaging performance than that of previously developed aperture synthesis systems that used moving platform. The improvement in performance is demonstrated by simulating the point source response, which shows the reduced sidelobes.