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。
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.
出处
《吉林大学学报（地球科学版）》
EI
CAS
CSCD
北大核心
2011年第2期572-578,共7页
Journal of Jilin University：Earth Science Edition
基金
国家自然科学基金项目(40974067
40774054)
吉林大学交叉学科项目(200810027
200903308)
关键词
地震勘探
时频峰值滤波
尺度变换
离散误差
随机噪声衰减
seismic prospecting； time-frequency peak filtering； signal scaling； discrete error； attenuation of random noise；
