Experimental Research on the Rule of Frequency-Band Derangement in Wavelet Packet Transform

The frequency-band derangement phenomenon of wavelet packet decomposition nodes, resulted from the defects of the DWT fast algorithms, is discussed. The rule of frequency-band derangement of wavelet packets nodes is studied with the method for signal processing experiments based on wavelet packets analysis, and then the means of adjusting frequency-band nodes in sequence is exploited. It is also found that the sequence of the adjusted wavelet packet nodes is the same as the Graycode, so with the idea of adjusting wavelet packet nodes, a new simple Gray coding algorithm is proposed.