Accession Number : ADP006392

Title :   Polarimetric Techniques and Measurements at 95 and 225 GHz,

Corporate Author : MASSACHUSETTS UNIV AMHERST MICROWAVE REMOTE SENSING LAB

Personal Author(s) : Mead, James ; McIntosh, Robert ; Langlois, Phillip ; Chang, Paul

Report Date : SEP 1991

Pagination or Media Count : 10

Abstract : The University of Massachusetts has developed two high-power portable polarimetric radars operating at 95 and 225 GHz. The 95 GHz coherent polarimeter is configured to measure the complex scattering matrix of a target by transmitting a pair of orthogonally polarized pulses in rapid succession. We have also developed a noncoherent 225 GHz polarimetric radar which directly characterizes the target Mueller matrix by transmitting a sequence of four or six polarization states. In addition to reviewing the radar design and calibration, this paper summarizes measurements of natural and man-made objects made to date. These measurements include several varieties of trees, terrain, and snowcover. A model which approximates the Mueller matrix with a single parameter is introduced for a restricted class of clutter and is found to accurately predict the polarimetric behavior of vegetation and terrain at low incidence angles. We also present a two parameter approximation of the Mueller matrix that accurately models scattering from snowcover at large incidence angles.

Descriptors :   *RADAR, *POLARIMETRY, *TARGET DETECTION, *RADAR ANTENNAS, ADDITION, ANGLES, BEHAVIOR, CALIBRATION, CLUTTER, HIGH POWER, MODELS, PARAMETERS, POLARIMETERS, POLARIZATION, POWER, PULSES, SCATTERING, SEQUENCES, TARGETS, TERRAIN, TRANSMITTING, TREES, VEGETATION, GROUND CLUTTER, MILITARY EQUIPMENT, SNOW COVER, AMPLIFIERS.

Subject Categories : Active & Passive Radar Detection & Equipment
      Optics

Distribution Statement : APPROVED FOR PUBLIC RELEASE