一种膛内多普勒测速修正方法

A Correcting Method of Doppler Velocity Measurement in Interior Ballistics

针对复杂电磁环境下膛内测速的重复性和精度低的问题,提出了一种非接触式膛内高精度测速方法,该方法在对膛内多普勒信号进行提取并去噪的基础上,利用S变换时频分析对预处理后的信号进行处理,然后采用谱峰搜索的方法来获得信号的瞬时频率,用能量重心校正法来提高结果精确度,最后根据多普勒原理,完成速度的测量;实验部分采用模拟信号和实际信号两种方式来验证该方法的可实施性;结果表明,该方法测速精度能够达到0.043 2%,相对于极值法和STFT法具有更小的误差。

Aiming at the problems of repeatability and low accuracy in measuring velocity under the enviroment of the complicated elec- tromagnetism in interior ballistics, the paper proposed a correction method to measure velocity with high accuracy. Based on extracting the Doppler signal and denoising it, the method used S transform time--frequency analysis to process the signal. Then the method of spectral peak searching was adopted to obtain the instantaneous frequency, and improved the precision with the method of energy centro--baric. Fi nally, the velocity was measured completely according to the principle of Doppler. In the experimental section the method adopted simulated signals and actual signals to verify that the method was practical. The results of experiment showed that the precision of it could reach 0. 0432%, and it had the smaller error compared to the extremum method and the STFT method.