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Stephen Cain

Publications and source records attributed to Stephen Cain.

2 recordsLinked to original sources

Flash light detection and ranging range accuracy limits for returns from single opaque surfaces via Cramer-Rao bounds.

A Cramer-Rao lower bound on the range accuracy obtainable by a Flash light detection and ranging (LADAR) system receiving a return from a single surface in the instantaneous field of view of each detector is developed and verified with experimental data. The bound is compared to the performance of a new algorithm and that of a matched filter receiver by using both simulated and measured LADAR data. The simulated data are used to show that the estimator is nearly unbiased and efficient for systems that match the negative paraboloid model used in its derivation. It is found that the achievable range accuracy for the LADAR system and for the target geometry used to collect the measured data is of the order of 2.5 in. while the bound predicts a range accuracy limit of approximately 0.6 in.

Journal Article↗

Optimized phase screen modeling for optical turbulence.

An alternative method for statistical interpolation is formalized. A new theorem is proved, providing theoretical basis for optimizing statistical accuracy in successively conditioned rendering applications. The theorem is empirically validated by two simulations, each comparing two different statistical interpolators. The interpolators are used to model high-resolution phase fluctuations over finite apertures. The theorem correctly predicts which interpolator is more optimal, based on empirical trials with greater than 99.9% certainty. The theorem is suitable as a quick alternative to the Monte Carlo optimization techniques used previously.

Journal Article↗