基于频移迭代的微波多普勒谱中心频率估计算法  

Estimation of mean frequency for microwave Doppler spectrum based on frequency offset iteration

作　　者：陈泽宗[1,2] 钟建波[1] 张龙刚[1] 陈曦[1] 

机构地区：[1]武汉大学电子信息学院,湖北武汉430072 [2]武汉大学地球空间信息技术协同创新中心,湖北武汉430072

出　　处：《华中科技大学学报（自然科学版）》2016年第2期70-74,共5页Journal of Huazhong University of Science and Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(41376182);海洋公益性行业科研专项资助项目(201205032);湖北省科技支撑计划资助项目(2014BEC057);国家海洋局数字海洋科学技术重点实验室2014年度开放基金资助项目(KLD021401);中央高校基本科研费专项资金资助项目(204214kf0028)

摘　　要：为了准确估计回波多普勒谱的中心频率,提出了一种基于频移迭代的中心频率估计方法.该方法以谱矩法估计频移为初值,逐次改变积分区间,在每次迭代中都利用谱矩法估计其频移,直至估计的频移结果收敛,并将该结果作为中心频率.仿真结果表明:相比于目前常用的谱矩法和最小二乘多项式拟合法,频移迭代法估计中心频率效果更佳,其平均绝对误差和均方根误差均更小,且该方法估计精度不受频率分辨率约束.将该方法应用于微波多普勒测波雷达中,并得到了海浪参数.实验结果证实:利用频移迭代法估计中心频率,可以探测得到更准确的有效浪高和平均浪周期.How to estimate mean frequency of the echo Doppler spectrum is a crucial issue for coherent microwave radar in detecting the wave parameters directly .To solve this problem ,a method of esti‐mating mean frequency based on frequency offset iteration （FOI） was considered in this paper .The initial frequency offset which was applied to FOI was obtained by using spectral moment （SM） meth‐od .Furthermore ,FOI method changed the integral range gradually to estimate frequency offset until the result move towards to convergence .This result was regarded as the final mean frequency .Com‐pared with the commonly SM and least square method based on polynomial fitting ,this method can obtain better simulated results ,and the mean absolute error （M AE） and the root of mean square error （RMSE） are lower by FOI .Especially the precision of FOI is not bound by the frequency resolution . The result which comes from FOI was applied to calculate wave parameters for microwave Doppler ra‐dar .The experiment results prove that more accurate results of significant wave height and average wave period can be obtained by using FOI .

关 键 词：微波多普勒雷达 多普勒谱 中心频率估计 频移迭代法 估计方法 

分 类 号：TN958.95[电子电信—信号与信息处理]