THEMIS

The THEMIS project aims to validate a UAV-based ground reflectance retrieval protocol. An artificial target is designed and manufactured, tuned to replicate the reflective behaviour of natural surfaces such as vegetation. The thorough knowledge of the geometrical and optical characterization of the target makes it possible to simulate its actual reflectance (“black sky”) with Eradiate. This target is then measured by a drone during a sunny day. The recorded reflectance (“blue sky”) is inverted using the CISAR algorithm, which retrieves the black sky reflectance from the experimental measurements, and the retrieved reflectance is compared to reference reflectance data simulated with Eradiate.