Effects of Horus Antenna Patterns on the Copolar Correlation of Weather Returns

The effects of phased array antenna patterns on copolar correlation coefficient of polarimetric radar are analyzed. Analytic expressions are derived and used to quantify biases in the copolar correlation coefficient caused by mismatch of beam widths for horizontal and vertical polarizations. Misalignment in the beams’ pointing direction is also considered. Measurements are made on an
$8\times 8$
panel of a polarimetric phased array radar (PPAR) under development by the Advanced Radar Research Center at the University of Oklahoma in collaboration with NOAA’s National Severe Storms Laboratory. The all-digital radar is called Horus and some measurements on a partially populated antenna are presented.