基于中值滤波的中频雷达延迟相关参数估计算法

      Estimation algorithm of delay correlation parameters for medium frequency radar based on median filtering

      • 摘要: 中频雷达可探测中高层大气风场,全相关分析(full correlation analysis, FCA)法是风场反演的常用方法之一。客观存在的大气环境干扰及雷达系统内部干扰可等效为接收机加性噪声,噪声可导致相关函数的形状畸变进而影响风速估计的准确性,回波降噪是中频雷达重要的信号处理步骤。本文将图像处理降噪方法引入中频雷达,提出基于中值滤波的延迟相关参数(median filtering based delay correlation parameters, MF-DCP)估计算法。为评价算法性能,提出风速估计加权均方误差指标,并将其分解为延迟相关参数均方误差的加权求和。通过理论分析、仿真实例及实测数据三方面证明,与现有广泛采用的拟合法相比,MF-DCP算法在低信噪比区域内能够获得更好的估计性能,同时还给出滤波窗口宽度的选取对估计性能及计算复杂度的影响,为MF-DCP算法在中频雷达工程实践中落地提供参考。

         

        Abstract: Medium frequency radar can detect the wind field in the middle and upper atmosphere, and the full correlation analysis method is one of the common methods for wind field inversion. The objective atmospheric environment interference and the internal interference of the radar system can be equivalent to the additive noise of the receiver, which can lead to the distortion of the shape of the correlation function and affect the accuracy of wind speed estimation, and echo noise reduction is an important signal processing step of medium frequency radar. In this paper, the image processing noise reduction method is introduced into the medium frequency radar, and median filtering based delay correlation parameters (MF-DCP) estimation algorithm. In order to evaluate the performance of the algorithm, the weighted mean square error index of wind speed estimation is proposed, and it is decomposed into the weighted sum of the mean square error of delay correlation parameters. Theoretical analysis and simulation examples show that compared with the existing widely used fitting method, the MF-DCP algorithm can obtain better estimation performance in the low signal-to-noise ratio region, and the influence of the selection of filter window width and hysteresis points on the estimation performance is also given, which provides a reference for the implementation of the MF-DCP algorithm in the engineering practice of medium frequency radar.

         

      /

      返回文章
      返回