一种简易的多普勒天气雷达速度退模糊方法

A simple method of velocity dealiasing for doppler radar

多普勒天气雷达提供的径向风场资料,是气象预报的重要判据之一.由于所探测到的风场信息存在着噪声、缺测和速度模糊等方面的问题,因此,多普勒天气雷达的速度退模糊技术也相应的受到越来越多的关注.文章根据多普勒天气雷达风场资料的特点,结合实际业务,提出了一种简易的速度退模糊方法.该方法在等距离圈切向和径线方向上进行速度退模糊.在等距离圈切向退模糊中,首先进行圈上的数据分段,然后检测段内和段间的速度模糊,再进行速度扩展退模糊.在径线方向退模糊中,从径线中点向外和向内检测速度模糊,然后进行速度扩展退模糊.进行了实例退模糊实验,证明了该方法的正确性和实用性.

Wind profile from Doppler radar is an important evidence for weather forecast. In the wind in- formation detected by Doppler radar, there exist problems such as noise, data missing and velocity alias- ing, therefore,velocity dealiasing is paid more and more attentions. In this paper, a simple method for velocity dealiasing is proposed according to the characteristics of wind profile and practical requirements. In the method, the velocities are dealiased in the tangent directions along the equally distant circles and in the radial directions along the radiations of the radar waves. In the tangent direction dealiasing, first, the velocity data are segmented. Next, the velocity aliasing within a segment and between segments are detected. Then, the aliased velocities are corrected by velocity unwrapping. In the radial direction dealiasing, the velocity aliasing is detected forward and backward from the center of a radiation. Then, the aliased velocities are corrected by velocity unwrapping. Practical dealiasing experiments have been done and show that the method is correct and applicable.