提高多普勒天气雷达晴空探测能力的一种方法

资助项目: 本文得到国家重点基础研究项目“我国重大天气灾害的形成机理和预测理论研究”的资助

A METHOD FOR IMPROVING THE PROBING ABILITY OF DOPPLER WEATHER RADAR IN THE CLEAR AIR

摘要: 该文通过对晴空大气返回信号特性的分析, 提出采用相干累积技术, 有可能提高多普勒天气雷达探测晴空大气的能力, 具体测算了提高探测能力的限度, 并对雷达信号处理器适应晴空探测进行了改进设计.
- 多普勒天气雷达;
- 相干累积;
- 晴空大气
Abstract:
By analyzing the characteristics of echo signal in the clear air, a coherent integral method is presented, which can improve the probing ability of Doppler weather radar in the clear air, and the limit of the improved ability is calculated. Based on the study, the design of the radar signal processor is improved to be applicable to the detection in the clear air.
- Doppler weather radar;
- Coherent integral;
- Clear air

图 1 改进后的雷达信号处理器原理框图

(虚线部分为用于晴空探测的增加部分)

下载: 全尺寸图片幻灯片

表 1 大气中C_n²值与其对应的等效反射率因子Z_eT

表 2 各种型号的新一代天气雷达的主要参数

表 3 新一代天气雷达最小可测等效反射率因子Z_emin (dBz) 随距离 (km) 的变化

表 4 S波段、C波段可进行相干累积的次数

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