Digital Calibration For Hrws Sar

In this paper, we present the development activity of digital calibration in the frame of the "High-Resolution Wide-Swath (HRWS) demonstrator" project. The goal of this work is to develop an effective digital calibration scheme for the performance optimization of the HRWS instrument, composed of independent digital receive channels both in elevation and azimuth. For the elevation channels, a real-time on-board calibration scheme is required and for the azimuth channels, on-ground calibration is possible. Our activity focuses on calibration scheme in elevation. The calibration scheme estimates imbalance between elevation channels by using sophisticate internal calibration signals and compensates it based on digital signal processing. This paper introduces the principle of digital calibration algorithm as well as possible implementation of it.