Development and Validation of a Polarimetric-MCScene 3D Atmospheric Radiation Model

Thermal infrared and solar regime multi- and hyper-spectral imaging is an invaluable tool for detecting the proliferation of weapons of mass destruction, but it does require that signatures from effluent gases or surface contaminants generated in processing of nuclear materials be distinguished from the ambient background. Contrast is increased and the extraction process enhanced, especially for man-made objects and perturbed backgrounds, by analyzing the polarimetric components of imaged spectral data. Unfortunately, there are no radiative transfer models that efficiently and accurately predict spectral channel polarized signal radiances, i.e., the Stokes parameters, within complex 3- dimensional environments. In response to this void, a validated, polarimetric 3- dimensional simulation capability will be developed by generalizing the Monte Carlo-based synthetic scene simulation model, P-MCScene, to include calculation of all 4 Stokes components. P-MCScene polarimetric optical databases will be generated by the government- standard band model algorithm MODTRAN6, which itself will be converted to a polarimetric model by integrating the newly revised and validated vector discrete ordinate, VDISORT2, model. Phase I is designed to set the groundwork for polarizing MODTRAN6 and MCScene, demonstrating a clear pathway to the Phase II goal of fully validated polarimetric models. The Phase I effort will focus on gathering relevant polarimetric databases and on initiating development of polarimetric MODTRAN6. A design and implementation plan for polarimetric MCScene will be generated. Validation field measurements will be planned.

Technical, economic, social, and national security benefits will arise from the successful completion of the proposed Phase II development and subsequent Phase III product commercialization. The technical benefit pertains to the development of greatly improved physics-based models and software tools to support the design and development of polarimetric optical sensors and their associated analysis algorithms for remote sensing applications. The economic benefit pertains to the potential time and cost savings that can be realized when sensor requirements and candidate designs can be rapidly and accurately evaluated using sensor/scenario simulation tools. The social benefit pertains to an improved capability to identify and monitor potential weapons of mass destruction production facilities. Tools developed under this program will enable design of improved sensors for weapons of mass destruction facilities monitoring. This in turn will provide our national decision makers and military commanders with more accurate and timely assessments of the status of our adversaries weapons of mass destruction programs.