The Imperfect Phase Pattern of Real Parabolic Radar Antenna and Data Quality

Abstract

Although antennas have well-known power patterns that are commonly used to understand the quality of measurements, they also have phase patterns that are difficult to obtain and are seldom discussed in the radar meteorological community. This study presents the characteristics of the antenna phase pattern of the McGill S-band radar. Phase variations in azimuth and elevation with respect to the main beam axis are obtained using high-resolution scans of an isolated ground target and of an emission source. The two-way phase pattern is relatively constant within the radar main beam, but it changes rapidly at the power minima between the main beam and the first sidelobe. The effects of this phase pattern on ground and weather targets were evaluated and were found to be much more pronounced for point targets than for distributed targets. Nevertheless, proper knowledge of the phase pattern of the radar antenna would enhance the ability to better select ground targets for radar refractivity retrieval and to estimate the quality of radar data.

Impact of Assimilating Radar Data with 3D Thermodynamic Fields in an Ensemble Kalman Filter: Proof of Concept and Feasibility

“…The potential impact of assimilating both radar data and retrieved thermodynamic information remains unclear, and most studies have focused on areas of strong convection. Themens and Fabry (2014) described the potential benefit of providing temperature and humidity information over 3D domains for mesoscale forecasting, and high-density thermodynamic information has been successfully retrieved from radar data Feng and Fabry 2016;Ellis and Vivekanandan 2011) despite some concerns related to accuracy and bias.…”