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The Method to Determine the Noise Power of Wind Profile Radar
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摘要: 风廓线雷达以测风为主要目的设计，没有充分考虑强度的定量测量。如果能够实现强度定量测量将大大扩展风廓线雷达的应用范围。首要的扩展应用就是可以获取雨滴谱分布、解决降水定量测量准确性问题。若实现强度定量测量，需要解决的一个关键技术问题是如何由其功率谱数据准确计算噪声功率。该文根据风廓线雷达功率谱估计方法、依据噪声频域统计特性，提出了一种计算风廓线雷达功率谱噪声功率的方法，并利用风廓线雷达实测功率谱数据进行检验。检验结果表明：即便在有降水或存在地物时，该方法仍可以准确、快速分辨出噪声功率谱, 且客观有效。Abstract: The main intention of designing wind profile radar is to obtain wind information of the atmosphere. However, it does not take full account of the function of intensity measurement. The applications of the wind profile radar will be greatly expanded, if the function of intensity measurement is implemented. A very important extension is to measure the process of precipitation and to get raindrop size distribution which can fundamentally improve the quality of quantitative measurement of precipitation. To achieve the intensity quantitative measurement, the key technical issue that must be solved is how to calculate the noise power accurately from power spectral density. Based on the power spectral density estimation method of wind profile radar adopted and the noise frequency domain statistical characteristics, a method to calculate noise power of wind profile radar is proposed and the validation of the method is done by using of wind profile radar measured power spectral density data. Results show that the method performs well. The power spectral density of noise can be separated accurately even in complex echo situation such as precipitation or strong surface clutter. The method is established on solid theory foundation. The calculation of noise power is accurately, quickly and efficiently, which looks forward to becoming a practical technology of wind profile radar.
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Key words:
- wind profile radar;
- power spectrum;
- noise power
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图 1 降水天气时确定噪声功率密度门限实例
(a) 实测功率谱，(b) 噪声功率谱，(c) 判别因子R随迭代次数变化
Fig. 1 Example of determining the threshold of noise power density on precipitation weather
(a) curve of power spectral density, (b) curve of noise power spectral density, (c) variation of discriminate factor R with iterations
图 2 强地物信号时确定噪声功率密度门限实例
(a) 实测功率谱，(b) 噪声功率谱，(c) 判别因子R随迭代次数变化
Fig. 2 Example of determining the threshold of noise power density in clutter environment
(a) curve of power spectral density, (b) curve of noise power spectral density, (c) variation of discriminate factor R with iterations
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[1] 张培昌, 王振会.大气微波遥感基础.北京:气象出版社, 1995. http://www.cnki.com.cn/Article/CJFDTOTAL-SYQY201603027.htm [2] 葛润生, 朱晓燕, 姜海燕.提高多普勒天气雷达晴空探测能力的一种方法.应用气象学报, 2000, 11(3):249-263. http://qikan.camscma.cn/jams/ch/reader/view_abstract.aspx?file_no=20000340&flag=1 [3] 何平, 朱小燕, 阮征, 等.风廓线雷达探测降水过程的初步研究.应用气象学报, 2009, 20(4):465-470. doi: 10.11898/1001-7313.200904011 [4] 黄伟, 张沛源, 葛润生.风廓线雷达估测雨滴谱参数.气象科技, 2002, 13(6):334-337. http://www.cnki.com.cn/Article/CJFDTOTAL-QXKJ200206002.htm [5] 尹忠海, 张沛源.利用卡尔曼滤波校准方法估算区域降水量.应用气象学报, 2005, 16(2):213-219. doi: 10.11898/1001-7313.20050226 [6] 胡明宝.风廓线雷达数据处理与应用研究.南京:南京信息工程大学, 2012. [7] 惠建新, 吴蕾, 高玉春, 等.基于极大似然算法的风廓线雷达谱矩估计.气象科技, 2012, 40(1):9-14. http://www.cnki.com.cn/Article/CJFDTOTAL-QXKJ201201003.htm [8] 何平.相控阵风廓线雷达.北京:气象出版社, 2006. http://www.cnki.com.cn/Article/CJFDTOTAL-SYQY201603027.htm [9] 李广柱, 陈少应, 高仲辉, 等.风廓线雷达噪声水平的估计研究.空军雷达学院学报, 2011(3):157-163. http://www.cnki.com.cn/Article/CJFDTOTAL-KLDX201103002.htm [10] 杨俊, 吕伟涛, 马颖, 等.基于自适应阈值的地基云自动检测方法.应用气象学报, 2009, 20(6):713-721. doi: 10.11898/1001-7313.20090609 [11] 陈豫英, 刘还珠, 陈楠, 等.基于聚类天气分型的KNN方法在风预报中的应用.应用气象学报, 2008, 19(5):564-572. doi: 10.11898/1001-7313.20080507 [12] 陈明轩, 俞小鼎, 谭晓光, 等.对流天气临近预报技术的发展与研究进展, 应用气象学报, 2004, 15(6):754-766. http://qikan.camscma.cn/jams/ch/reader/view_abstract.aspx?file_no=20040693&flag=1 [13] 陈明轩, 王迎春, 俞小鼎.交叉相关外推算法的改进及其在对流临近预报中的应用.应用气象学报, 2007, 18(5):690-701. doi: 10.11898/1001-7313.20070505 [14] 陆光华.随机信号处理.西安:西安电子科技大学出版社, 2002. http://www.cnki.com.cn/Article/CJFDTOTAL-SYQY201603027.htm [15] 胡广书.数字信号处理.北京:清华大学出版社, 2003. http://www.cnki.com.cn/Article/CJFDTOTAL-SYQY201603027.htm [16] 张贤达.现代信号处理.北京:清华大学出版社, 2002. http://www.cnki.com.cn/Article/CJFDTOTAL-SYQY201603027.htm [17] 赵树杰.信号检测与估计理论.北京:清华大学出版社, 2005. http://www.cnki.com.cn/Article/CJFDTOTAL-SYQY201603027.htm -
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