Sensitivity of Polarimetric Weather Radars

The ability to reliably detect and process weak returns is an important performance aspect of meteorological radars. This paper reviews the theory, requirements, and design considerations supporting weak signal detection for polarimetric weather radars. The original requirements for the WSR-88D included an ambitious specification for sensitivity resulting in excellent clear air detection performance. Modern receiver hardware and advanced signal processing provide adequate detection of signal returns to support today’s polarimetric radars that divide transmitter power between two channels. Wavelength considerations are included along with important hardware and signal processing features such as noise estimation and mitigation. This paper presents an assessment of the sensitivity performance of the polarimetric WSR-88D and addresses sensitivity as an important aspect of forecast and warning operations.