PORTABLE HYPERSPECTRAL TUNABLE IMAGING SYSTEM (PHyTIS) FOR PRECISION AGRICULTURE

Hyperspectral remote sensing can provide contiguous spectra of scenes made up of dozens to hundreds of narrow wavebands, across the visible and near-infrared portions of the spectrum. This emerging technology provides spatial and spectral information that can be acquired simultaneously. Presented here for use in agricultural research is the Portable Hyperspectral Tunable Imaging System (PHyTIS). It is a computer-controlled, liquid-crystal tunable filter, digital imaging system designed to extract spectra of typical agronomic scene components (endmembers) such as sunlit and shaded leaves and soil for spectral mixture analysis. Results from a scene acquired in a cotton (Gossypium hirsutum L.) field showed that scene components could be successfully unmixed and area of each quantified. Image processing and hyperspectral remote sensing can identify endmembers to quantify crop biophysical parameters, to derive fractional cover maps, and could be used as inputs to plant, soil, and evapotranspiration models.