Electrical and Computer Engineering ETDs

Publication Date

5-5-1972

Abstract

This study presents an investigation of the polarization of infrared waves due to propagation through the atmosphere. Cumulus cloud and Haze M particle size distributions are considered for various optical depths at wavelengths of 4.0 and 10.0µ. Results at these wavelengths are compared to results at a wavelength of 0.5µ for the same physical atmosphere. Initially the radiative transfer integral equations are derived which include the Stokes polarization vector. From these integral equations a Monte Carlo simulation technique is used to simulate photon histories through the atmosphere. The effects of multiple scattering on the polarization state of the scattered intensity is included. A diffuse scattering ground which causes complete depolarization of the incident intensity is included in the simulation model. Numerical results are obtained for cloudy and hazy atmospheres. It is shown that the degree of depolarization is a function of atmospheric particle density and wavelength, thereby leading to the conclusion that in a linear, homogeneous, isotropic scattering medium, depolarization is a result of multiple scattering. Significant depolarization at wavelengths of 0.5 and 4.0µ is shown to occur for cumulus clouds and optical depths of 3.0 when the cloud is 1km in height. Polarization factors are obtained with and without ground reflections, with ground albedos playing a significant part in the polarization of the backscatter intensity. Detectors are judiciously placed below and above the cloud layer so that forward and backscatter are measured.

Document Type

Dissertation

Language

English

Degree Name

Electrical Engineering

Level of Degree

Doctoral

Department Name

Electrical and Computer Engineering

First Committee Member (Chair)

Ahmed Erteza

Second Committee Member

Arnold Herman Koschmann

Third Committee Member

Martin D. Bradshaw

Download

Share

COinS