'Concept and Performance of Internal Instrument Calibration for Multi-Channel SAR'

The increased complexity of multi-channel SAR sensors and the real-time on-board phase/amplitude correction requirement poses new challenges for the calibration, which cannot rely on current calibration techniques. On the other hand, the digital hardware utilized in multi-channel SAR systems, offer entirely new opportunities for the calibration such as on-board error correction and digital calibration. An internal calibration strategy for future digital beamforming SAR instruments is detailed and its performance analyzed using a dedicated calibration simulator

An Analytical Error Model for Spaceborne SAR Multichannel Azimuth Reconstruction

In the context of spaceborne synthetic aperture radar (SAR) for remote sensing, multichannel system architectures coupled with digital beamforming techniques are deemed a necessary technological advancement to fulfil the requirements for near future radar missions. Calibration of such systems is an important topic, since channel imbalances may lead to considerable degradation of performance. This paper analyses the impact of residual errors in a SAR system with multiple channels in azimuth and derives an analytical model for the resulting performance degradation, which may be used in system design as an aid to establish requirements in an error budget analysis