Title:
ADAPTIVE FILTER
Document Type and Number:
Japanese Patent JP3732167
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To always realize a normal adaptive operation.
SOLUTION: In order to negate noise transmitting through an exhaust duct 1 with an acoustic wave emitted from a secondary sound source loudspeaker, a Filtered-x LMS algorithm executing part 8 controls the transfer function W of a filter 3 so that the composite transfer function of the transfer function W of an FIR adaptive digital filter 3 and a transfer function C occurring between the filter 3 and an error microphone 6 becomes equal to the transfer function P of the exhaust duct 1. In order to constitute its control system from a Filtered-x LMS algorithm, the amplitude or the phase of the transfer function CI of an FIR digital filter 7 with an identified transfer function C is changed until it becomes equal to the transfer function C when the transfer function C is changed.
Inventors:
Kiyohiro Kurisu
Application Number:
JP2002244643A
Publication Date:
January 05, 2006
Filing Date:
December 20, 1995
Export Citation:
Assignee:
TOA Co., Ltd.
International Classes:
G10K11/02; G10K11/178; G10K11/16; H03H21/00; (IPC1-7): G10K11/178; G10K11/02; H03H21/00
Domestic Patent References:
| JP7253790A | ||||
| JP5040486A | ||||
| JP5066783A | ||||
| JP5008694A | ||||
| JP7253792A | ||||
| JP7032947A |
Attorney, Agent or Firm:
Masatoshi Kimura