Statistical Properties of the Dual-Polarization Differential Reflectivity (ZDR) Radar Signal

Abstract

The statistical characteristics of three estimators of the differential reflectivity (ZDR) radar signal are examined theoretically and compared with pulse-to-pulse measurements of reflectivity at horizontal and vertical polarizations. The square-law and log-ratio estimators provide satisfactory means for measuring ZDR while the log-ratio estimator does not. In addition, the theory is consistent with radar data, clearly showing that ZDR could be measured accurately from a sequence of alternately polarized waves.