5 September 1989 Maximum Likelihood Approach To Gamma Circumvention
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A critical element in the Time Dependent Processing chain for scanning infrared sensors is electronic gamma circumvention. The most successful approach to gamma circumvention to date is a two stage algorithm, Spike Adaptive Time Delay and Integration (SATDI). This heuristic approach makes no assumptions about gamma-induced noise except that it is an additive corruption of the true signal. If, however, one can model the form of the gamma-induced noise distribution, it is possible to design a maximum likelihood estimation model which explicitly utilizes the parametric form of the noise. Such a model will, in general, be more efficient than a heuristic one, since it contains more information about the noise process. The parametric form studied in this paper is an exponential distribution, λe-λr, where r is the received signal. This distribution is a reasonable approximation to the observed gamma spectrum in infrared detectors. A maximum likelihood estimation equation corresponding to this noise distribution is derived, and its performance is compared to SATDI. It is found that, for a bright gamma background, either much better detection for a fixed false alarm rate, or many fewer false alarms for a fixed detection probability, may be achieved using the maximum likelihood estimator as compared to SATDI.
© (1989) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
P. C. Trepagnier, "Maximum Likelihood Approach To Gamma Circumvention", Proc. SPIE 1096, Signal and Data Processing of Small Targets 1989, (5 September 1989); doi: 10.1117/12.960346; https://doi.org/10.1117/12.960346

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