A simulation is describe which determines in detail the response of visible through infrared focal plane devices, used in space-based electro-optical imaging sensors, to proton irradiation from the natural space environment, as a function of the choice of orbit around the earth. The quantitative description of the natural environment (protons) is based on the NASA code AP-8 and/or the CRRES database. Simplified shielding models and other models are then used to obtain the impinging proton environment, including the proton: flux, energy distributions, and trajectories, just above the surface of the focal plane in question. The interaction of a single proton with the focal plane is modeled based on the focal plane semiconductor material, the 3D pixel geometry, and the focal plane layout. This model is then exercised in a Monte-Carlo simulation to build up the aggregate focal plane response effects due to the variety of protons encountered under appropriate orbital and shielding conditions. The output of this simulation is statistically analyzed and used to construct a database to enable system planners and architects, algorithm developers, and sensor data users to mitigate the unwanted effects of this radiation.
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