Maj David M. Strong (Air Force Institute of Technology)
Keywords: Imaging
Abstract:
The intent of this paper is to extend a previously developed statistical model of a polarimetric sensor to include atmospheric effects on the spatial frequency bound. Initial estimates of the spatial frequency resolution are attained through calculation of the Cramer-Rao lower bound for a two-channel polarimeter in a vacuum. The definition of maximum spatial frequency resolution for this research is when the highest spatial frequencies observed just meet the noise floor. Previous results for the model in a vacuum showed that the spatial resolution bound is lowered as the degree of polarization in the image is varied from 0 to 1. Before pursuing a blind deconvolution algorithm for a polarimeter it is important to understand the impact of atmospheric effects on the spatial frequency bound. The model used for the polarimeter imaging system is an ideal two-channel polarimeter with an output of two images of orthogonal polarizations. Models of the atmosphere with various amounts of turbulence are then added to the polarimeter imaging system model to determine the impact on the spatial frequency bound. The number of Zernike coefficients used to model the atmospheric distortions and their impact on the spatial frequency bound is also explored. Additionally, the impact on the bound through the use of a simulated adaptive optic system to reduce the atmospheric turbulence effect on the polarimeter images is shown. The data produced by the developed models is then used to determine the potential for developing new algorithms to improve existing polarimeter imaging capabilities.
Date of Conference: September 10-14, 2006
Track: Imaging