Download or read book Atmospheric Propagation in the Middle-Infrared and at 8-14 Micrometers written by J. Stacey and published by . This book was released on 1973 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study considers the problems of propagation through the lower troposphere in the middle-infrared and in the 8 to 14 micrometer regions of the spectrum. The atmospheric constituents that scatter and absorb energy at these wavelengths are identified and the losses are calculated for several air-to-ground transmission paths. Examples of the atmospheric transmission losses are calculated for several passive sensor bandpasses and for a radar at 10.59 micrometers. In these examples, the atmospheric constituents that contribute to the total propagation loss over the sensor bandpass are individually identified and the accumulated losses are separately reported as a function of slant range. The performance for active and passive sensors is calculated and plotted for a host of weather conditions. Variations in rain rates, fog densities, and haze visibilities are introduced to demonstrate the relative degradation to the S/N for the sensor system. Aircraft measurements of atmospheric constituents are examined to determine if an empirical relationship exists between haze visibility and slant-path transmittance. Empirical expressions for haze attenuation are derived for selected wavelengths in the middle-infrared region and at 10.59 micrometers. Attenuation from common chemical smokes is estimated.