Research of Signal Amplitude Changing Wavelet De-noising Method

Signal de-noising using conventional orthogonal wavelet transform often exhibits pseudo Gibbs phenomenon in the vicinity of signal discontinuities. To suppress such defect, signal amplitude changing wavelet de-noising method was proposed in this paper. In this method, the original corrupted signal was pre-processed before the wavelet de-noising stage and post-processed after that stage. In this way, for the discontinuities were removed from the signal, the cause for the appearance of visual artifacts was eliminated and the de-noised signal without pseudo Gibbs phenomenon was obtained. In order to testify the effectiveness of the method, its de-noising capability was compared with that of translation-invariant de-noising method and conventional wavelet de-noising method by simulations. The results indicate that the de-noising performance by the method proposed in this paper is improved in terms of pseudo Gibbs phenomenon suppress and output signal to noise ratio. Therefore, signal amplitude changing wavelet de-noising method provides an effective solution for signal de-noising.