Estimating Signal-to-Clutter Ratio of InSAR Corner Reflectors From SAR Time Series

Estimating Signal-to-Clutter Ratio of InSAR Corner Reflectors From SAR Time Series

Czikhardt, Richard (Slovak University of Technology in Bratislava)
van der Marel, H. (TU Delft Mathematical Geodesy and Positioning)
van Leijen, F.J. (TU Delft Mathematical Geodesy and Positioning)
Hanssen, R.F. (TU Delft Mathematical Geodesy and Positioning)

2021

The estimation of Signal-to-Clutter Ratio (SCR) of a radar point target, such as a corner reflector, is an essential step for synthetic aperture radar (SAR) interferometry and positioning, as it influences the phase measurement variance as well as the absolute positioning precision. The standard method to estimate the SCR of a point target relies on the debatable assumption of spatial ergodicity, using the clutter of the surrounding as representative of the clutter at the point target. Here, we estimate the SCR of a corner reflector using a time series of SAR measurements, i.e.,\ assuming temporal ergodicity. This assumption is often more realistic, particularly in a complex environment, in the presence of other point scatterers, and for small-sized reflectors. Empirical results on a corner reflector network, using Sentinel-1 SAR measurements, show that the temporal method yields a less biased and more precise estimate of the average SCR. A second experiment shows that the InSAR phase variance as well as positioning precision, predicted using SCR estimated by the temporal estimation method, is closer to the truth.

Corner reflector (CR)
InSAR phase variance
SAR interferometry (InSAR)
SAR positioning
radar-cross-section (RCS)
signal-to-clutter ratio (SCR)
synthetic aperture radar (SAR)

http://resolver.tudelft.nl/uuid:25d16aca-5b82-4fdd-a153-b9e2629df26e

https://doi.org/10.1109/LGRS.2021.3070045

1545-598X

IEEE Geoscience and Remote Sensing Letters, 19

Institutional Repository

journal article

© 2021 Richard Czikhardt, H. van der Marel, F.J. van Leijen, R.F. Hanssen