Imaging with Synthetic Aperture Radar

A Theoretical Emergency Kit for SAR Imagery


The propagation and polarization of electromagnetic waves


The electromagnetic radiation of microwave antennas


Interaction between waves and natural surfaces


Elements of signal processing






SAR Processing: At the Heart of the SAR Technique


Introduction


General principles of Synthetic Aperture Radar


Frequency representation


SAR Synthesis algorithms


System constraints


Geometry characteristics


An introduction to super-resolution


Radar processing and geometric specificity of bistatic data



From SAR Design to Image Quality


Introduction


Radar equation, Radar Cross Section (RCS) of a point target


Radar signature for extended targets - the backscatter


Signal to noise ratio (SNR) of the radar-target link before SAR synthesis


Modifying the SNR during SAR synthesis


Instrument Noise Equivalent σ0(NEσ0inst)


Impact of image ambiguities on the NEσ0inst - total


Volume of data generated onboard


Telemetry data rate


Calibration and corresponding image quality requirements


Speckle noise and image statistics


The impulse response (IR)


Radiometric elements of Image Quality


Geometric elements of image quality


Radar image interpretation






SAR Interferometry: Towards the Ultimate Ranging Accuracy


Principles and limitations of radar interferometry


Implementing interferometry processing


Application for topography


Application for displacement measurement


How slope effects limit interferometry


Interpreting the results


Availability and mission perspectives


Comparison of interferometry with other methods


Robustness of coherent processing when faced with ambiguities


Permanent reflectors






SAR Polarimetry: Towards the Ultimate Characterization of Targets


Introduction


Radar polarimetry: operating principle


The scattering matrix


Standard forms of backscatter


Polarization synthesis


Characteristic polarization and Euler parameters


Coherent decomposition of the polarimetric measurement


Taking depolarization into account


Covariance matrix - coherence matrix


Incoherent decomposition of polarimetric measurements


Practical cases of polarimetric analysis


Synoptic representation of polarimetric information


Future compact polarimetric systems


Merging polarimetry and interferometry: PolInSAR


Conclusion