基于时窗熵的冲击波到时提取方法研究

Research on a method of shock wave arrival time extraction based on time window entropy

摘要:

针对冲击波超压场大区域、全过程重建的需求，开展冲击波到达时间的高精度提取方法研究，首先，分析了STA/LTA的冲击波到达时间提取模型，其次结合信息论理论提出了基于时窗熵的冲击波到达时间提取方法，再次通过仿真实验比较了不同噪声条件下本文的到达时间提取精度，对比了两种方法在同一噪声条件下的提取精度，分析结果表明本方法的提取精度在不同噪声条件下基本保持在0.77%，在低信噪比条件下，本方法的提取精度高于STA/LTA约6%，保证了低信噪比条件下冲击波到达时间的提取精度，解决了STA/LTA方法对于信号变化幅度小而发生漏拾的情况，避免了不必要的提取误差，实现了更高精度的冲击波到达时间的提取具有更高的提取精度，能够为大区域的冲击波超压场高精度重建提供有效的到达时间特征参数，在高价值弹药毁伤效能参数中具有一定的理论意义和工程使用价值。

Abstract:

To meet the needs of large area and whole process reconstruction of the shock wave overpressure field, the high-precision extraction method of the shock wave arrival time was studied. First, the shock wave arrival time extraction model of STA/LTA was analyzed, and then the shock wave arrival time extraction method based on the time window entropy was proposed in combination with the information theory theory. Thirdly, the extraction accuracy of the shock wave arrival time under different noise conditions was compared through simulation experiments, The extraction accuracy of the two methods under the same noise condition is compared. The analysis results show that the extraction accuracy of this method is basically kept at 0.77% under different noise conditions. Under the condition of low signal to noise ratio, the extraction accuracy of this method is about 6% higher than that of STA/LTA, which ensures the extraction accuracy of shock wave arrival time under the condition of low signal to noise ratio, and solves the problem that STA/LTA method misses the detection due to small signal change amplitude, It avoids unnecessary extraction errors, realizes higher precision extraction of shock wave arrival time, has higher extraction precision, can provide effective arrival time characteristic parameters for high-precision reconstruction of shock wave overpressure field in large areas, and has certain theoretical significance and engineering use value in damage effectiveness parameters of high-value ammunition.