摘要
针对传统时频分布分析的时频分布图能量聚集性差、交叉项干扰严重且对噪声敏感的问题,提出了一种基于Wigner高阶谱的膛内运动弹丸回波信号处理方法。对仿真信号从能量聚集性、交叉项抑制、抗噪声三个方面进行比较研究,结果表明Wigner高阶谱进行高阶多项式调频信号瞬时频率估计具有优势。对某型炮弹实测数据采用基于MATLAB的Wigner三谱对角切片算法获得时频分布图。提取时频分布图的时频脊线得到瞬时频率曲线。由多普勒效应公式反演出膛内弹丸的速度、加速度曲线。与实验结果相比:炮口速度相对误差为1.34%,弹丸运动距离与炮管实长的相对误差各为0.52%。验证了在强噪声环境下,Wigner高阶谱分析是膛内运动弹丸回波信号处理的一种更准确有效的方法。
In view of the problems of the time-frequency distribution map of traditional time-frequency distribution analysis that has poor convergence of energy, serious cross-term interference and noise sen- sitivity, a method for the signal processing of the echo of projectile motion in bore is proposed based on Wigner higher-order spectrum. The advantages of Wigner higher-order spectrum on the instantaneous frequency estimation of higher-order polynomial frequency modulation signals are verified through the comparative study of energy concentration, cross-term suppression and anti-noise. The time-frequency distribution map is obtained by the Wigner trispectrum slice spectrum algorithm designed on MATLAB for the measured data of a certain type of projectile. An instantaneous frequency curve is obtained through the ridge extraction of time-frequency distribution map. The velocity and acceleration curves of in-bore projectiles are inversed according to the Doppler effect formula. Compared with the experimental results ,the relative errors of the muzzle velocity, the range of projectile motion and the real length of the barrel are 1.34% ,0.52% and 0.52%. It is indicated that the Wigner higher-order spectrum is a more accurate and effective method on the echo signal processing of projectile motion in bore under strong noise environment.
出处
《南京理工大学学报》
EI
CAS
CSCD
北大核心
2012年第3期442-447,共6页
Journal of Nanjing University of Science and Technology
关键词
高阶谱
弹丸
膛内运动
时频分析
回波信号
高阶多项式
调频信号
higher-order spectra
projectiles
motion in bore
time-frequency analysis
echo signals
higher-order polynomial
frequency modulation signals
