摘要
水中航行物的辐射噪声中的线谱特征通常被用来提高声呐的检测性能,本文用线谱特征来估计水中航行物的距离和速度。文中给出了四条水中航行物的时变谱图像和线谱图的例子,从这些例子中可以看到线谱非平稳性的一些时频形态,线谱非平稳反映的航行状态变化和由于辐射噪声与水声信道相互作用产生密集的干涉条纹等现象。文章指出了其中有二组特征蕴藏的目标距离和速度信息,线谱和干涉条纹。利用Dopplerlet变换和匹配投影算法提取到线谱中蕴藏的目标距离和速度信息。用计算机模拟验证了本方法的可行性,编写了较好的算法,并调查了算法的性能。在此基础上,从海上实验数据中估计出水中航行物的距离和速度,其估计值与海上实验实际的距离和速度相符。
The line spectrum of moving vessel radiated-noise is usually used to improve sonar detection performance ('line components' occurring at discrete frequecies in a spectrum is called 'line spectrum'). A new method to estimate range and speed of a moving vessel by a nonstationary characteristics of line spectrum is presented. And four spectrogram examples of the moving vessel radiated-noise are provided, which show some time-frequency characteristics including line spectrum nonstationary, the variance of moving state reflecting by line spectrum nonstationary and the interference patterns caused by interactions between the radiated-noise and the acoustic channel. It indicates there are two kinds of characteristics containing the information of range and speed, the Doppler line spectrum and the interference pattern. Dopplerlet transform and matching pursuit are used to estimate range and speed. The result of the computer simulation shows the method is practicable and effective. Moreover, the range and speed estimation of the real underwater data on the sea conform to the on site results.
出处
《声学学报》
EI
CSCD
北大核心
2003年第2期130-136,共7页
Acta Acustica
基金
国家自然科学基金资助项目(19974060)
