Digital beamforming: A paradigm shift for spaceborne SAR

Spaceborne Synthetic Aperture Radar (SAR) provides high-resolution, day-and-night and weather-independent images for a multitude of applications ranging from geoscience and climate change research, environmental monitoring, global 2-D and 3-D mapping, change detection, 4-D mapping (space and time), security-related applications up to planetary exploration. By means of the development of new digital beamforming and waveform diversity technologies in combination with large reflector antennas, future SAR systems will outperform the imaging capacity of current systems by two orders of magnitude. This paper provides an overview of the state of the art in spaceborne SAR and describes the technological developments that will open the door to a future global remote sensing system for the continuous observation of dynamic processes over the Earth surface.