Adaptive Optimized Sidelobe Weighting to Spaceborne DBF SAR System in Elevation

Abstract

Spaceborne Synthetic Aperture Radar (SAR) is a powerful remote sensing tool for large scale Earth observation. The combination of Scan-On-Receive (SCORE) mode and digital beamforming (DBF) has been proposed to improve signal-to-noise ratio and attenuate the range ambiguities. Although advantageous, the shape of the narrow receive beam may affect the chirp signal spectrum and introduce pulse extension loss. Considering that the pulse extent on the ground varies from the near range to the far range, this paper proposes a novel real-time operation mode based on optimized sidelobe weighting to the receive channels, which reduces the pulse extension loss and the range ambiguity, particularly at large incidence angle.