手法を比較

	音声明瞭度	FxLMS アクティブノイズコントロール
分野	音響学	音響学
系統	Process / pipeline	Process / pipeline
提唱年	1980	1975
提唱者	Herman Steeneken, Tammo Houtgast	Bernard Widrow, Samuel Stearns
種類	Speech clarity assessment method	Adaptive noise cancellation algorithm
原典	Steeneken, H. J., & Houtgast, T. (1980). A physical method for measuring speech-transmission quality. Journal of the Acoustical Society of America, 67(1), 318–326.	Widrow, B., & Stearns, S. D. (1975). Adaptive signal processing for active vibration and noise control. IEEE Transactions on Acoustics, Speech, and Signal Processing, 23(5), 440–453.
別名	intelligibility metrics, STI, Speech Transmission Index, clarity index	FxLMS, filtered-x LMS, active noise cancellation, ANC
関連	5	5
概要	Speech intelligibility is a quantitative measure of how well listeners understand spoken content in acoustic environments. Formalized by Steeneken and Houtgast in 1980 with the Speech Transmission Index (STI), intelligibility metrics combine room acoustic parameters (RT60, noise, clarity) to predict listener comprehension. Understanding speech intelligibility is essential for designing classrooms, offices, hearing aids, and public address systems where clear communication is critical.	The Filtered-x Least Mean Squares (FxLMS) algorithm is an adaptive filter used in active noise control (ANC) systems to reduce unwanted sound by generating anti-noise. Pioneered by Widrow and Stearns in 1975 and refined by Eriksson and colleagues, FxLMS is the most widely deployed algorithm in commercial noise-canceling headphones, hearing aids, automotive cabins, and industrial noise barriers. It works by continuously learning the acoustical path and dynamically adjusting a canceling signal in real time.