Comparative analysis of information capacity for space surveillance systems in 3- to 5- and 8- to 14-um spectral ranges

摘要

Abstract: The information capacities of infrared optoelectronic systems are not identical in the middlewave (3 - 5 $mu@m) and longwave (8 - 14 $mu@m) ranges of spectrum. The analysis of the so-called quality factor, rendering the preference to range 8 - 14 $mu@m at underlaying surface temperature below 40, does not take into consideration the system spatial resolution, which depends upon a fundamental factor - the wavelength, and therefore can not serve as a decisive argument in choosing a photodetector and a spectral range for an IR surveillance system. The paper is concerned with informational characteristics of a specific system depending upon a spectral range. It is shown that, despite more low resolution of optical system, the spectral range 8 - 14 $mu@m nevertheless, in a basic interval of informational frequencies (nearly up to Nyquist frequency) has the advantage in comparison with the range 3 - 5 $mu@m as on temperature, as on spatial resolution.!4