Along Track Interferometry on Rhone River

The Along Track Interferometry technique has been experimented on a RAMSES X band radar dataset. The concept behind ATI is to compare the phase of SAR images obtained from two receive antennas, separated in the along-track direction. This phase difference is coding the velocity of targets moving towards or away from the radar, within a mono-pass acquisition. Potential applications are numerous, nevertheless in this work we applied ATI technique to estimate river surface currents. The study areas were over the Rhone river at two locations, first one is near Beaucaire where the Rhone river has a large annual discharge rate and the second one is the Rhone estuary. This paper describes the RAMSES radar dataset that has been acquired in a dedicated fight and results obtained applying ATI technique. The surface velocity maps and profiles computed are promising, and are consistent with ground measurements that have been done simultaneously to the RAMSES radar data acquisitions. Such velocity maps could then constitute a support for hydrologists to drive numerical models and contribute to river discharge monitoring.