Temporal Decorrelation impacts on repeat pass tomography in a tropical forest

The objective of this paper is to provide a better understanding of the impact of temporal decorrelation on the tomography phase of the P-band Synthetic Aperture Radar (SAR) BIOMASS mission, 7-th Earth Explorer of the European Space Agency. In this context, in the framework of the Phase A studies of the BIOMASS mission, the airborne TropiSAR 2009 and ground-based TropiScat 2011 experiments were conducted over the site of the tropical forest Paracou, French Guiana. The P-band SAR tomographic data acquired during TropiSAR campaign allowed us to reconstruct 3-D high resolution data, whereas TropiScat experiment provided vertical temporal coherence of the vegetation. These data therefore allow us to generate a BIOMASS P-band SAR data stack that accounts for both the 6 MHz bandwidth limit and temporal decorrelation. To do this, we developed a tomo-graphic simulator, which can combine 3-D high resolution data from TropiSAR and the temporal decorrelation from TropiScat data-sets, to provide the most realistic temporal BIOMASS tomographic data. The resulting tomograms and forest heights were observed to change acceptably as long as the revisit time is 4 days or less. Therefore, the revisit time for the BIOMASS tomographic phase at 3-4 days as proposed should be feasible.