@techreport{oai:ipsj.ixsq.nii.ac.jp:00232486,
 author = {藤井, 健作 and 棟安, 実治 and 苣木, 禎史 and Kensaku, Fujii and MItsuji, Muneyasu and Yoshifumi, Chisaki},
 issue = {16},
 month = {Feb},
 note = {本報告では，Filtered-x 法の動作を不安定化させる原因が騒音制御フィルタを線形とする仮定が崩れることにあることを示す．実際，Filtered-x 法は騒音制御フィルタが線形とみさせる程度に係数が緩やかに更新されるとの仮定の下で導かれている．この仮定を学習同定法で満たすためには，設定するステップサイズを小さくする必要がある．しかし，それは騒音制御フィルタの収束を遅らせる．本報告では，ステップサイズ制御を適用したブロック実行型学習同定法で騒音制御フィルタの係数を更新すれば，遅延は妥当な大きさになることを示す．, In this paper, we show that active noise control systems using the filtered-x algorithm become unstable where the noise control filter reduces the degree of linearlity. The filtered-x algorithm is derived under the assumption that the noise control filter is linear. The assimption, however, requires applying a small step size to the normalized least mean square (NLMS) algorithm updating the coefficients of the noise control filter, which delays the convergence of the filter. We shows that the delay can be redused by updating the coefficients with the block implementation type NLMS algorithm jointly using the step size control method proposed by the authors.},
 title = {Filtered-x法型能動騒音制御システムを安定に動作させる条件について},
 year = {2024}
}