火箭发动机装药包覆层厚度信号处理技术研究

用超声测量火箭发动机装药包覆层厚度时,当包覆层较薄时检测回波信号会出现时域混叠。基于时域混叠信号的特点,提出了一种时间延迟估计的新方法。该方法用维纳解卷积消除了检测始波对时间延迟估计的影响，并对剩余信号进行了三次能量倒谱分析，准确直观地估计出了信号延迟时间。该方法已在开发的超声探伤系统中得到了验证。实验结果表明，该方法能准确估计出时域混叠信号的延迟时间，提高了火箭发动机装药包覆层厚度的测量精度。

Signal Processing Research for Rocket Motor Cladding Thickness

When the cladding thickness of rocket motor is measured with ultrasonics, the test echoes of the thin cladding will overlap in the time field. Based on the characters of overlapped echoes, a new method for time delay estimation is presented. This method firstly removes the effect of reference signal on time delay estimation, then the triple cepstrum of remain signal is made, finally estimates the time delay of signals accurately. This method has been proved in the ultrasonic cladding testing system developed in our research center. Experimental results show the method can estimate the delay time of the overlapped signals accurately. It improves the measurement precision of rocket motor cladding.