| As the traditional technique, Fourier analysis is a good method to process the test signal collecting from ship, but this method has one shortcoming. Due to processing signals only in frequency field, Fourier analysis can not show the differences on a certain time spot when signals have any jumps on the time axis. The jumps have to be evenly distributed to the whole time axis. And with the special advantages in processing time-variant signals, the rapidly developing wavelet analysis become a very efficient method to process signals in both time and frequency fields. It has a great future in the fields of de-noising, filtering and strengthening signal which collecting from real ship vibration.In this paper, I firstly introduce the reasons in the background of selecting the subject and its research meaning, generalize the history and the status of wavelet analysis and make comparison with Fourier analysis. At the same time, I explain the research idea and method of the whole paper.Secondly, based on working on the main theory of wavelet and different usual wavelet functions, I mainly discuss noise characters of ship, the method of choosing different wavelets for different vibration signals and the rule of choosing gate value. And I also define the formula of evaluating wavelet de-noising performance and compile the MATLAB program to analyze 1-D and 2-D signals with noise.At last, I mainly place emphasis on analyzing real experiment signal on the ship. Based on the comparison of SNR, I find out the most suitable wavelet and wavelet shrinkage for this kind of signal. At the same time, with the expansion of wavelet I apply periodic wavelet to de-noise special signal with heavy noise and obtain a good result.
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