Investigation of Extensions to the Distorted Born Approximation in Strong Fluctuation Theory

• Main Author: Stogryn, A.
• Other Authors: AEROJET ELECTROSYSTEMS CO AZUSA CA
• Format: Text
• Language: English
• Published: 1988
• Subjects: Snow; Ice and Permafrost; Active & Passive Radar Detection & Equipment; *SNOW COVER; *SEA ICE; *RADAR CROSS SECTIONS; *ELECTROMAGNETIC SCATTERING; MOMENTS; TEMPERATURE; INCOHERENT SCATTERING; DIELECTRIC PROPERTIES; BRIGHTNESS; CORRELATION; EMISSIVITY; ICE; ANISOTROPY; SYMMETRY; FUNCTIONS(MATHEMATICS); SCALAR FUNCTIONS; NUMERICAL METHODS AND PROCEDURES; SCATTERING CROSS SECTIONS; LAYERS; COMPUTATIONS; ELECTRIC FIELDS; Ice; permafrost; Sea ice
• Online Access: http://www.dtic.mil/docs/citations/ADA203698; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA203698

This study, considers some scattering problems relevant to the analysis of brightness temperatures and scattering cross sections of sea ice and its snow cover. The work reported here to examines how the heretofore neglected contribution of the incoherent field to the emissivity and scattering cross sections of a random medium may be taken into account. Two main technical problems which are solved. Strong fluctuation theory equations are derived for the second moments of the electric field in an anisotropic medium. A derived equation is the basis for a detailed reduction of the second moment equation to a form which is practical for numerical computation. The problem of a layered medium with a spherically symmetric correlation function is considered. The spherical symmetry of the correlation function implies that a scalar description of the dielectric properties of the medium is valid and results in the elimination of several technical problems which would arise had an anisotropic correlation function been assumed. Thus, the theory is applicable to snow cover on sea ice as well as old sea ice (provided that the correlation functions describing brine pockets in the ice is spherically symmetric as is suggested by some studies) but will not be directly applicable to young and first year ice which are anisotropic.