一种Alpha稳定分布噪声下的体积目标长度估计方法

Estimation of Volume Target Length in Alpha Distribution Noise

为了解决Alpha稳定分布噪声环境下运动舰船目标的长度估计问题,该文借鉴非线性变换抑制脉冲噪声以及多普勒目标运动特性估计思想,提出基于广义时频分析(G-TFA)和最小二乘估计的运动目标长度估计方法。该方法首先利用G-TFA获取Alpha稳定分布噪声环境下运动目标的多普勒频率,然后利用最小二乘方法估计出目标航速和不同位置的横正时刻,最后利用上述估计结果计算目标长度。以广义Winger-Ville分布(G-WVD)为例,从理论上推导了G-TFA在Alpha稳定分布噪声环境下具有提取目标多普勒特征的能力,并通过仿真实验验证了该算法在中低混合信噪比下的稳健性。与现有算法相比,该文所提算法不需要估计噪声特征指数,算法性能优于基于传统时频分析的估计方法。

In order to estimate the length of moving ship targets in Alpha stable distribution noise,a moving target length estimation method based on Generalized Time-Frequency Analysis(G-TFA)and least squares estimation is proposed,which utilizes nonlinear transform to suppress impulsive noise and Doppler effect to estimate target motion characteristics.The method uses G-TFA to obtain the Doppler frequency of moving targets in a stable distributed noise environment.Then,the least squares method is used to estimate the target speed and the closest point of approach time of different positions.Finally,the target length is calculated using the above estimation results.Taking Generalized Winger-Ville Distribution(G-WVD)as an example,the ability of G-TFA to extract Doppler features in Alpha stable distributed noise is theoretically derived.The robustness of the proposed method under low-to-medium mixed signal-to-noise ratio is verified by simulation experiments.Compared with the existing methods,the proposed method does not need to estimate the noise characteristic index,and the performance is better than the methods based on the traditional time-frequency analysis.