Jian-wei JIANG(蒋建伟)1, Yu-jun FANG(房玉军)1,2, Li-zhen W AN(万丽珍)1, Jian-bing MEN(门建兵)1
1. State key Laboratory of Explosion Science and Technology, Bei jing Institute of Technology, Beijing 100081, China 2． China South Industry Research Academy, Beijing 100086, China
Abstract-It’s a problem to be solved how to de-noise the sig nal of blast shock wave overpressure. In the conventional methods, the high freq uency of the signal is cut directly by some mathematics algorithms, such as Four ier Transform, but some of the useful signal will be cut together. We adopt a ne w method for the signal de-noising of shock wave overpressure by wavelet analys is. There are four steps in this method. Firstly, the original signal is de-com posed. Then the time-frequency features of the signal and noise are analyzed. T hirdly, the noise is separated from the signal by only cutting its frequency whi le the useful signal frequency is reserved as much as possible. Lastly, the usef ul signal with least loss of information is recovered by reconstruction process. To verify this method, a blast shock wave signal is de-noised with FFT to make a comparison. The results show that the signal de-noised by wavelet analysis a pproximates the ideal signal well.
Key words-blast shock wave, signal, noise, wavelet anal ysis
Manuscript Number: 1674-8042(2010)02-0145-03
dio: 10.3969/j.issn.1674-8042.2010.02.11
Reference
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