Hyperspectral Remote Sensing Technology (HRST) program

The Office of Naval Research (ONR) and the Naval Research Laboratory (NRL) are currently in the design phase of a program called the Hyperspectral Remote Sensing Technology (HRST) program. HRST will demonstrate the utility of a hyperspectral earth-imaging system to support Naval needs for characterization of the littoral regions of the world. One key component of the HRST program is the development of the Navy EarthMap Observer (NEMO) satellite system to provide a large hyperspectral data base. NEMO will provide images of littoral regions with 210 spectral bands over a bandpass of 0.4 to 2.5 mu m. Since ocean environments have reflectances typically less than 5%, this system requires a very high signal-to-noise ratio (SNR). The NEMO Hyperspectral Imager (HSI) will sample over a 30 km swath width with a 60 m Ground Sample Distance (GSD) with the ability to go to a 30 m GSD by utilizing the systems attitude control system to "nod" (i.e., use image motion compensation/ground motion compensation to slow down the ground track of the field of view). Also included in the payload is a co-registered 5 m panchromatic imager to provide simultaneous high spatial resolution imagery. A sun-synchronous circular orbit of 605 km allows continuous repeat coverage of the whole earth. A unique aspect of the system is the use of a feature extraction and data compression software package developed by NRL called the Optical Real-Time Spectral Identification System (ORASIS). ORASIS employs a parallel, adaptive hyperspectral method for real time scene characterization, data reduction, background suppression, and target recognition. The use of ORASIS is essential for management of the massive amounts of data expected from the NEMO HSI system, and for developing Naval products under HRST.