| 摘要 |
PURPOSE:To remove noise even in such a case that a signal shape is deformed by the superposition of noise and a target signal or the S/N ratio of a measuring signal is small. CONSTITUTION:When the teacher signal Ni(t) of noise and the teacher signal Sj(t) of a target signal are given to a wavelet coefficient filter forming device 2 and the conversion coefficient row of all of teacher signals obtained by a wavelet converter 4 is set to WS+N (t, a) and the conversion coefficient row only of the teacher signal of the target signal is set to WS (t, a) and WS+N (t, a) is inputted, a filter F (W) obtaining a coefficient row nearest to WS (t, a) is formed by a filter forming device 5. When a mixed signal V(t) containing noise is applied to a wavelet filter device 3, a wavelet conversion coefficient row WV (t, a) is calculated by a wavelet converter 4' and the above mentioned filter F (W) is applied by a filtering device 6 to form a coefficient row WV (t, a) which is, in turn, inverted by a wavelet power inverter 7 to obtain a signal V (t) from which a noise component is removed. |
