Abstract:

The improved time-frequency peak filtering (TFPF) method is proposed in order to reduce the stairs errors at the segmentation points. By studying the discrete error caused by frequency modulation and peak filtering in time-frequency plane, and scaled processing, we find that the stairs errors are inversely proportional to the length of discrete Fourier transform, and also related to the varying value scaled from zero after signal scaling. TFPF based on the fixed zero signal scaling is proposed, and converts the zero to the fixed value in the range of instantaneous frequency to reduce the departure from zero, so that the stairs error are decreased. The results of TFPF processing for simulation and real seismic signals show that the improved TFPF can effectively attenuate the random noise and reduce the steps of sub filter at the sub-section.

Key words: seismic prospecting, time-frequency peak filtering, signal scaling, discrete error, attenuation of random noise