Radar clutter under non-standard RF propagation. The surface-based duct creates increased sea clutter, formation of clutter rings, and increased radar range for low altitude targets.A large portion of the work done in ESL such as remote sensing, satellite systems, GPS, wireless communications, scattering, and radar systems requires an accurate understanding of the propagation in various parts of the atmosphere.
Some of these include multipath environments such as urban areas, groundwaves, ionospheric propagation, non-standard propagation such as atmospheric ducting, terrain diffraction, tropospheric scattering, rain and clouds.
At ESL we work on a broad spectrum of RF propagation topics spanning scattering, reflection, refraction, diffraction, polarization, and absorption that significantly affect RF propagation.
Effects of inhomogeneous atmospheric refractivity on RF propagation. Vertical variation of index of refraction due to an evaporation duct at the ocean surface and a surface-based duct formed due to marine boundary layer. The coverage diagram obtained by parabolic equation model and sea clutter vs. range.
Faculty/Researcher Contacts: Dr. Robert Burkholder, Prof. Joel Johnson, Dr. Caglar Yardim
Propagation loss vs. range for a TV station off the coast of Norfolk, VA measured by Research Vessel (R/V) Knorr during Trident Warrior 2013 Experiment. Large difference between standard atmospheric conditions and measured RF loss, especially at beyond line-of-sight due to tropospheric scattering.