Observation Strategies for TanDEM-X and Tandem-L

Abstract:
TanDEM-X is a unique mission to derive Digital Elevation Models (DEMs) with two SAR satellites in orbit since 2007 and 2010. The acquisition of the first global DEM was performed until 2014. After a first science phase was performed between 2014 and 2017, an update of the global DEM, called “Change DEM”, was acquired between 2017 and 2020. Currently, a second science phase is carried out concentrating on permafrost areas, forests and the major cities of the world. DLR is also pushing for the time after TanDEM-X with Tandem-L, a proposal for a sophisticated satellite-duo operating in L-band, serving a variety of applications. The paper describes the acquisition concepts for both missions which are of crucial importance for delivering high-quality DEM data to scientific and commercial users.