气象学报2022，Vol.80Issue(5)：791-805,15.DOI:10.11676/qxxb2022.059
适用S波段多普勒天气雷达的径向速度自动退模糊方法
Automatic radial velocity dealiasing algorithm for S-band Doppler weather radar
摘要
Abstract
Radial velocity ambiguity limits the application of radar velocity data. To address the issues of the ambiguity of isolated echo or echo isolated by distance ambiguity and clutter interference as well as the problem in traditional method that takes radial straight line as initial reference in velocity dealiasing algorithm, a new automated Doppler radar velocity dealiasing algorithm is proposed. (1) Two zero velocity curves are obtained by finding the zero velocity junction point to roughly partition positive and negative velocity regions. After the positive and negative zoning, the clutter interference area and non clutter interference area are identified. For the clutter interference area, whether it meets multiple conditions with ambiguity characteristics is determined point by point. For the non clutter interference area, the ambiguity boundary is determined to delineate the ambiguity area block for dealiasing, which is conducted at the remaining points. (2) If the zero velocity curves cannot be determined, either the zero velocity curves information recorded in the upper layer is used or the qualified radial linear zero velocity line is searched. (3) If the zero speed line still cannot be determined, whether it meets multiple conditions with ambiguity characteristics will then be determined point by point. The algorithm is verified by using 3407 velocity ambiguity volume scan data of 11 cases such as squall lines, hails and strong typhoons observed by S-band radar, and the overall accuracy is higher than 98%. Using the zero velocity curves to determine the positive and negative zones, identifying the ambiguity area blocks and considering the extended neighborhood search in point by point judgment are conducive to the dealiasing processing of isolated echoes and echoes isolated by distance ambiguity. This method is more effective than the operational method. For the hail case that occurred on 4 March 2018, the accuracy is 10%higher than that by the operational method. Using the method of determining whether it meets multiple ambiguity feature conditions point by point for the clutter interference area, the ambiguity points can be successfully removed without being affected by the clutter. Comprehensive consideration of the upper zero velocity line and relevant information in the image that is helpful to determine the zero velocity curves and strict examination and test can ensure the accuracy of the zero velocity curve, which is conducive to the successful processing of velocity dealiasing.关键词
多普勒天气雷达/速度退模糊/径向速度/质量控制/0速线Key words
Doppler weather Radar/Velocity dealiasing/Radial velocity/Quality control/Zero velocity line分类
天文与地球科学引用本文复制引用
韩颂雨,刘永生,骆阳,杨明,罗昌荣..适用S波段多普勒天气雷达的径向速度自动退模糊方法[J].气象学报,2022,80(5):791-805,15.基金项目
浙江省气象科技计划项目（2021QN20、2020ZD16）、浙江省气象局智能网格预报重点创新团队。 （）
