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摘要: 针对双极化气象雷达中非气象回波的滤除问题,该文提出一种基于詹森-香农散度原理的自适应移动谱去极化比(AMsDR)滤波方法。该方法根据不同方位向回波的谱去极化比分布情况,利用气象回波和杂波在距离-多普勒图上的特征差异实现气象回波的保留和杂波的滤除。与现有固定阈值的移动谱去极化比滤波器相比,AMsDR滤波方法可根据不同方位向降雨和杂波的回波差异自适应地选择滤波阈值,提高杂波抑制与降雨保留性能。Abstract: This paper proposes an adaptive filtering method called the Adaptive Moving spectral Depolarization Ratio (AMsDR) filter to mitigate the clutter for dual-polarization weather radar based on Jensen-Shannon divergence principle. Specifically, the spectral depolarization ratio in the range-Doppler domain is the main variable distinguishing precipitation from clutter. The AMsDR filter can remove the clutter and noise and retain precipitation based on the difference of the spectral polarization feature and the spectral continuity of precipitation and clutter. The AMsDR filter can adaptively select the filter threshold depending on the echo difference between precipitation and clutter in different azimuths. Thus, the performance of the proposed filter is better than that of the current methods.
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表 1 IDRA雷达参数
Table 1. IDRA radar specifications
参数 数值或属性 类型 线性FMCW 发射机类型 固态 极化类型 ATSR模式 中心频率 9.475 GHz 发射功率 20 W 扫描时间 409.6 μs 带宽 5 MHz 天线宽度 1.8° 扫描角 俯仰角0.5°
方位角0°~360°扫描周期 1圈/min -
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