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 fulfill the requirements for near-future spaceborne radar missions. Calibration of such systems is an important topic, since channel imbalances may lead to considerable degradation of their performance. This letter analyzes 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.