| 摘要 |
A symmetric unit filter (L 10 '') is designed by combining in series two unit filters ( 1 L 10, 2 L 10 ) having asymmetric numerical sequences as filter coefficients (H 1 to H 3 and H 4 to H 6 ). Thus, by designing a filter by series connection, it is possible to automatically obtain a desired digital filter coefficient only by combining one type of unit filter (L 10 '') in series. Moreover, a symmetric numerical sequence {-1, 0, 9, 16, 9, 0, -1}/32 is divided at the center into two parts and one of them is used as the asymmetric filter coefficients (H 1 to H 3 and H 4 to H 6 ). This reduces the number of necessary taps, eliminates use of a window function, and prevents generation of a discretization error in the filter characteristic obtained.
|
