PROBLEM TO BE SOLVED: To increase the followability to the variation of the basic frequency of a power source.SOLUTION: A basic frequency calculation part 10 calculates the basic frequency of the ignition pulse signal which drives an engine 3. A signal generation part 11 generates the sine wave signal of a specific order of frequency among the harmonic frequencies of the basic frequency, and the plural different frequencies of sine wave signals in the range which is determined based on the variation characteristics of the driving frequency of the engine 3 to the specific order frequency as reference. An adaptive filter part 13, which comprises adaptive filters 20 which operates according to the LMS algorithm for each of plural sine wave signals generated in the signal generation part 11, each adaptive filter 20 inputs the corresponding sine wave as the reference signal, and each adaptive filter 20 inputs the voice signal which is input in a voice input part 12 as an error signal, and outputs the output signal which is acquired by summing the signals outputted from each adaptive filter 20. A voice output part 14 outputs the voice corresponding to the output signal.SELECTED DRAWING: Figure 1
【課題】動力源の基本周波数の変化に対する追従性を高める。【解決手段】基本周波数算出部10は、エンジン3を駆動する点火パルス信号の基本周波数を算出する。信号生成部11は、基本周波数の倍数次の周波数のうちの特定次数の周波数の正弦波信号と、特定次数の周波数を基準としエンジン3の駆動周波数の変動特性に基づいて定められた範囲内の複数の異なる周波数の正弦波信号とを生成する。適応フィルタ部13は、LMSアルゴリズムに従って動作する適応フィルタ20が、信号生成部11で生成された複数の正弦波信号各々について設けられ、各適応フィルタ20は、対応する正弦波信号を参照信号として入力し、各適応フィルタ20が音声入力部12で入力された音声信号を誤差信号として入力し、各適応フィルタ20から出力された信号を加算して得られる出力信号を出力する。音声出力部14は、出力信号に対応する音声を出力する。【選択図】図1
NOISE CONTROL DEVICE, NOISE CONTROL METHOD AND POWER MACHINE
騒音制御装置、騒音制御方法及び動力機械
2018-05-24
Patent
Electronic Resource
Japanese
ACTIVE NOISE CONTROL DEVICE, ACTIVE NOISE CONTROL METHOD, AND ACTIVE NOISE CONTROL PROGRAM
European Patent Office | 2022
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