南昌双偏振天气雷达地物杂波抑制效果分析

为评估南昌CINRAD/SAD双偏振天气雷达对地物杂波的抑制效果，使用2019年6—10月南昌单偏振雷达基数据和2022年同期南昌双偏振雷达基数据，对比分析了不同仰角和晴、雨条件下单、双偏振天气雷达反射率频率。结果表明：单、双偏振雷达在0.5°仰角因周边山区地形、建筑物遮挡的影响，在西北方向和东南方向存在明显的数据缺失。升级为双偏振雷达后，在各个仰角上周围反射率高频区的范围明显减小，雷达能有效消除雷达站点周边杂波的影响。晴天时，双偏振雷达对晴空杂波的过滤效果极佳；雨天时，双偏振雷达对南昌周边及梅岭山区的回波进行了弱化处理，可以有效减少地形回波、非气象回波的干扰。双偏振天气雷达产品差分相移率和相关系数能较清楚地辨别出虚假回波，可更好地用于确定降水粒子的信息。

Analysis of ground clutter suppression effect of Nanchang dual polarization weather radar

To evaluate the suppression effect on ground clutter of Nanchang CINRAD/SAD dual polarization weather radar, the base data of Nanchang single polarization radar from June to October 2019 and Nanchang dual polarization radar during the same period in 2022 were used, comparative analysis of single and dual polarization weather radar reflectivity frequencies under different elevation angles, sunny and rainy conditions. The results indicate that due to the influence of surrounding mountainous terrain and building obstruction in Nanchang, both the single and dual polarization radar had obvious data missing in the northwest and southeast directions at 0.5° elevation angle. After upgrading to dual polarization radar, the range of the high frequency area of surrounding reflectivity was significantly reduced at each angle, the radar can effectively eliminate the interference of surrounding clutter. In sunny days, the dual polarization radar exhibited an excellent filtering effect on clear sky clutter. In rainy days, the dual polarization radar weakened the echoes around Nanchang and Meiling Mountain area, and can reduce the interference of terrain echoes and non meteorological echoes, and the dual polarization products differential phase shift rate and correlation coefficient can distinguish false echoes clearly, and can be better used to determine the informations of precipitation particles.