随机相位编码在多普勒天气雷达中的应用

Application of Random Phase Code in Doppler Weather Radar

利用多普勒天气雷达观测中小尺度强对流天气系统时,为了避免产生速度模糊,往往需要采用比较高的重复频率,这时远距离回波就会产生折叠,且与正常回波混叠在一起,使数据质量大为下降。文中介绍了距离折叠产生的机制,阐述了使用随机相位编码退距离折叠的原理,并结合某型X波段多普勒天气雷达对该技术进行了成功的应用。实际探测结果表明,使用随机相位编码技术可以有效解决多普勒天气雷达的距离折叠问题,但也会在一定程度上使真实回波有所减弱,并消去边缘的弱回波。

In the doppler weather radar, especially when observing middle-little scale system of strong convection weather, in order to avoid velocity ambiguity, high PRF is usually adopted. Thus, the far echo will be ambiguous and fixed together with the normal echo. The quality of the radar data will be decreased. The mechanization of range ambiguity and how to use random phase code to mitigate range ambiguity is introduced in detail. Then, this technology is used in one X-Band doppler weather radar. The detecting result shows that using random phase code can efficiently solve the problem of range ambiguity in the doppler weather radar. At the same time, the real echo will be crippled in some extent and the weak echo at the side will be removed.