Spaceborne Radar Sensing of Precipitation above an Ocean Surface: Polarization Contrast Study

Abstract This feasibility study explores the potential benefits of polarization adjustment for spaceborne radar sensing of precipitation. More specifically, the role of the wave polarization in separating or “distinguishing” ocean surface return from the hydrometeor echoes of a “chirped” signal is examined. To that end, experimental as well as computational data for the polarization scattering matrices of hydrometeors and ocean surfaces are obtained and used to calculate ocean and precipitation “response” to the transmitted pulse for various rain rates and incidence angles. The analysis is restricted to X and C bands, but simulations are performed for several signal-to-noise ratios, rain rates, and ocean surfaces. The problem is further restricted to the monostatic case (same polarizations for transmitter and receiver). Even when the ocean and hydrometeor echoes are mixed throughout the entire radar resolution volume, the results appear promising. It is found that polarization, which provides the best con...