Filtering optimal selection method for leakage sound wave signals of gas transmission line

The invention discloses a filtering optimal selection method for leakage sound wave signals of a gas transmission line. The method includes the steps that the falling edge length of the leakage sound wave signals serves as the signal length of signals with the amplitude suddenly falling to the amplitude which restores to zero; the time domain waveform of true leakage sound wave signals is fitted to obtain fitted leakage sound wave signals; noise signals are added, so that pseudo leakage sound wave signals are obtained; filtering processing is conducted on the pseudo leakage sound wave signals through various pre-selected filtering methods, and the waveform after filtering is obtained; the evaluation index of the filtered signals is calculated and obtained, the optimal filtering method is determined, and the effectiveness of the optimal filtering method is verified through the true leakage sound wave signals. According to the filtering optimal selection method for the leakage sound wave signals of the gas transmission line, the requirements of SNR evaluation index maximum, root-mean-square error evaluation index minimum and leakage falling edge amplitude loss evaluation index minimum are met, the optimal filtering method is selected, the filtering effect of the leakage sound wave signals is quantificationally evaluated, the SNR of the leakage sound wave signals is increased, and the applicability of a sound wave method leak detection technology is improved.