Predictive Polarimetry Atmospherics Closure System (PPACS)

AFRL/VSSS is the lead Air Force group for providing the DoD community with physics-based predictive models critical to assessing the utility of optical spectro-polarimetric sensing (SPS) for aerospace reconnaissance and target cueing. AFRL/VSSS ispresently upgrading the government-standard MODTRAN atmospheric radiance code to properly handle polarization. However, there is currently no means of deducing the model inputs to properly represent aerosol composition variability, which has strong impacton target polarized signatures . Even for identical optical haze (thickness) levels, the unknown aerosol type can vary the sky degree-of-polarization by a factor of 2. The absence of a facility to gauge in-field aerosol properties to enable modelcomparisons to field measurements consequently threatens to obstruct development and maturation of spectro-polarimetric predictive models.To remedy this situation, Aerodyne Research, Inc (ARI) proposes a multi-firm team (ATA, SSI, Professor Aragon/SFSU) to design, implement, test, and deliver the Predictive Polarimetry Atmospherics Closure System, or PPACS, a facility which includes both themeans of gauging the aerosol conditions during field measurements, and of rendering this information into suitable form for MODTRAN4-P. The Predictive Polarimetry Atmospherics Closure System, or PPACS, will serve a need that will grow in scope andrecognition as MODTRAN4-P and spectropolarimetric sensing are increasingly employed across the remote sensing and reconnaissance communities. The target market consists of government defense (e.g. DoD) and civilian (e.g. NASA) test ranges, EO/IR systemtest contractors, and research institutions engaged in spectropolarimetric field measurements and modeling.