Method for calibrating the antenna alignment of an SAR sensor

Abstract

The invention relates to a method for calibrating the antenna alignment of an SAR sensor with one or more transmission antennas and one or more receiving antennas. Each receiving antenna is connected to an analog-to-digital converter for digitizing the SAR signal received by the receiving antenna in order to form SAR raw data. The plurality of digitized echoes, which are transmitted and received using a specific antenna combination, constitute an SAR raw data channel. According to the method, correction parameters are determined for the viewing direction of a plurality of antennas of at least one group of antennas of the SAR sensor. The method for calibrating the antenna alignment of the SAR sensor has the following steps: in step a), a reference target analysis is carried out in which the signature of a plurality of reference targets in the SAR raw data are compared with modeled signatures, and a residual response of the signatures is determined for each reference target and for each SAR raw data channel; in step b), the residual responses for each reference target in the SAR raw data channels of the group of antennas are fused, whereby a fused residual response is obtained for each reference target; and in step c), the correction parameters for the viewing direction of a plurality of antennas of at least one group of antennas of the SAR sensor are determined from the fused residual response.

Images