Effect of Earth Albedo Variation on the Performance of a Spatial Acquisition Subsystem Aboard a Planetary Spacecraft
نویسنده
چکیده
The effect of Earth albedo variation on the pointing and tracking subsystem of a planetaly optical communication package is analyzed. By studying the Cramer-Rao bound of the tracking error variance, it is shown that, when the Earth albedo is precisely known, the variance in spatial tracking error is inversely proportional to the total signal count. In contrast, a small uncertainty in the Earth albedo can result in an irreducible error in the tracking subsystem.
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تاریخ انتشار 2003