Phase calibration of TanDEM-X ATI-SAR data for sea surface velocity measurements
Paper in proceedings, 2017

It has been demonstrated that Along Track Interferometric (ATI) SAR is a useful tool to retrieve ocean surface currents. The ATI SAR provides an interferometric phase (hereafter called phase) which is directly related to the Line-Of-Sight (LOS) component of the surface velocity. The accuracy of ocean currents retrieval is highly dependent on the phase processing. For instance, a properly processed phase must equal zero over static targets. The measured TanDEM-X phase rarely (if ever) satisfies this condition which indicates a phase offset independent of the surface properties. The offset can be either due to a phase synchronization issue or to using inaccurate orbital and attitude information in the processing. The objective of phase calibration is the estimation and the removal of the offset and possible trends from the measured phase. In this paper, the topographic phase is simulated using a Digital Elevation Model (DEM) and baseline information. The calibration is carried out by estimating the average of the phase over land, after topography correction, and subtracting the estimated value from the measured phase. Finally, the residual phase trend is removed using a second order polynomial fitting.

synthetic aperture radar

oceanography

ocean surface currents

TanDEM-X

radar interferometry

Author

Anis Elyouncha

Microwave and Optical Remote Sensing

Leif Eriksson

Microwave and Optical Remote Sensing

Roland Romeiser

Lars Ulander

Microwave and Optical Remote Sensing

IEEE International Geoscience and Remote Sensing Symposium (IGARSS)

2153-7003 (eISSN)

922-925

Roots

Basic sciences

Subject Categories

Electrical Engineering, Electronic Engineering, Information Engineering

Oceanography, Hydrology, Water Resources

DOI

10.1109/IGARSS.2017.8127103

ISBN

9781509049516

More information

Latest update

3/27/2018