【摘要】 提出减少时频峰值滤波分段点处阶跃误差的改进方法。经过研究时频峰值滤波在频率调制和时频平面峰值滤波时产生的离散误差以及尺度变换方式,发现分段点处阶跃误差与离散傅里叶变换的长度成反比,且与零点在尺度变换后产生的不确定值有关。提出基于定零点尺度变换的时频峰值滤波,在信号尺度变换时将零点变换到瞬时频率区间上的固定值,使各段时频峰值滤波零点偏移量一致,从而消除分段点处的阶跃误差。仿真实验和实际地震信号时频峰值滤波处理结果表明,改进的时频峰值滤波算法能够有效消减随机噪声,减少分段滤波在分段处的阶跃。更多还原

【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.更多还原