Calculation of the Attenuation Coefficients of 0.6-14 Micrometer Waves Passing Through Fog
Abstract
Precise and approximate equations are derived for use in determining the coefficient of attenuation alpha 1/km of electromagnetic waves in mists and fogs. The simplified equations are given in unabsorbed polydispersed aerosols and absorbed polydispersed aerosols. Comparative calculations were made for several laser wavelengths in the spectral windows of atmospheric transparency. The optical properties of the water drops used as sols, droplet sizes used, and the mean droplet radii were given. Results obtained in a given calculation using a M-20 electronic computer and those obtained in using given equations are tabulated. They indicate that the use of these approximate equations results in errors which are only about 18 percent larger than those derived from precise and tedious equations. Electromagnetic waves in the 10-12 mu spectra passed through fogs with minimal attenuation. In heavy, optically dense fogs (for short wavelengths) the coefficient of attenuation was not selective.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 08, 1970
- Accession Number
- AD0714786
Entities
People
- E. R. Milyutin
- I. L. Zelmanovich
- L. M. Lobkova
Organizations
- National Air and Space Intelligence Center