In-scene wavelength calibration of the airborne hyperspectral imaging sensor MAHI

We describe an in-scene technique for accurate wavelength calibration of our airborne MAHI (Mid-infrared Airborne Hyperspectral Imager) sensor using modelled atmospheric spectral features. MAHI operates in the 3.3 to 5.4 μm region with a spectral sampling of 3.3 nm. The new technique significantly improves the accuracy over a lab technique using plastic film spectral features. We demonstrate the technique’s performance against: poorly known spectral response function; error in the initial wavelength grid guess; and deviation of the measured pixel spectra from the reference atmospheric spectrum. Performance of the new calibration technique for a recent airborne campaign in the Los Angeles area is demonstrated.