| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a digital filter capable of calculating parameters, depending on the frequency variation, which can be acquired with inexpensive configuration. <P>SOLUTION: In a digital filter calculating y<SB>n</SB>=A y<SB>n-1</SB>+B (x<SB>n</SB>-x<SB>n-1</SB>), a parameter calculating section 10 is set up to calculate parameters A and B, depending on the frequency variation. The parameter calculating section 10 can be acquired with a simple constitution, consisting of a frequency measuring instrument 11, a nonvolatile memory 12 storing the rated frequency and a plurality of constants C to D preliminarily, a plurality of multipliers 14 and 16, and a plurality of subtractor 13, 15, and 17. <P>COPYRIGHT: (C)2008,JPO&INPIT |
