Refining a hyperspectral and multiangle measurement concept for vegetation structure assessment

The concept of combining multiangle and hyperspectral remote sensing has been developed and utilized in the compact high-resolution imaging spectrometer (CHRIS) satellite observation system onboard the project for on-board autonomy (PROBA) platform developed by the European Space Agency (ESA). Recent studies show that this technology is useful for extracting crop and soil information, and it is very promising for deriving forest structural and biochemical parameters. However, hyperspectral measurements at multiple angles appear to have much redundancy. Therefore, we attempt to refine this measurement concept by testing a new system that acquires hyperspectral signals only in the nadir direction but measures in two additional directions in two spectral bands, namely red and near-infrared (NIR). According to our recent research, we propose that the best two view angles are (i) the hotspot, where the Sun and view directions coincide; and (ii) the darkspot, where the sensor sees the maximum amount of vegetati...