基于频谱Sevcik维数的目标运动速度估计*

在声目标无源估计应用中,目标与接收器存在相对运动时,接收的目标辐射的噪声信号存在多普勒频移。多普勒频移中包含目标的运动参数信息。针对线谱信号多普勒频移目标运动参数获取问题,提出一种基于频谱Sevcik维数的目标运动速度获取方法。首先利用Doppler-warping变换对接收信号进行重采样,然后对重采样后的频谱信号求Sevcik维数,最后通过寻找Sevcik最小值来实现速度估计。仿真证实了所提方法的有效性,在相同仿真条件下,所提方法相较于频谱求熵算法,速度搜索结果不仅具有更窄的主瓣宽度,而且可提高抗噪性5dB左右。两组实验数据的速度估计误差小于5%,证明了本文算法的有效性。

Estimation of target velocity based on Sevcik dimension of spectrum

In acoustic target passive estimation applications, when there is motion relative to the target, there is a Doppler shift in the noise signal radiated by the received target. The Doppler shift contains information about the motion parameters of the target. Aiming at the problem of obtaining the motion parameters of the Doppler shift target of the line spectral signal, a method for obtaining the motion speed of the target based on the Sevcik dimension of the spectrum is proposed. The Received Signal is resampled using the Doppler-warping transform, then Sevcik dimensions are obtained for the resampled spectral signal, and finally the speed estimate is achieved by looking for the Sevcik minimum. Simulation confirms the effectiveness of the proposed method, under the same simulation conditions, the proposed method compared with the spectrum entropy algorithm, the speed search results not only have a narrower main lobe width, but also can improve the noise immunity of about 5dB. The speed estimation error of the two sets of experimental data is less than 5%, which proves the effectiveness of the proposed algorithm.