手法を比較

	部屋のインパルス応答	音響ホログラフィ	Beamforming
分野	音響学	音響学	音響学
系統	Process / pipeline	Process / pipeline	Process / pipeline
提唱年	1965	1985	1988
提唱者	Manfred Schroeder	James Maynard, Earl Williams, Yongjian Lee	Van Veen, Barry Buckley
種類	Measurement pipeline for room acoustics	Sound field reconstruction method	Directional audio array processing
原典	Schroeder, M. R. (1965). New method of measuring reverberation time. Journal of the Acoustical Society of America, 37(6), 409–412.	Maynard, J. D., Williams, E. G., & Lee, Y. (1985). Near-field acoustic holography: I. Theory of generalized holography and the development of NAH. Journal of the Acoustical Society of America, 78(4), 1395–1413.	Van Veen, B. D., & Buckley, K. M. (1988). Beamforming: A versatile approach to spatial filtering. IEEE ASSP Magazine, 5(2), 4–24.
別名	RIR, impulse response measurement	NAH, near-field acoustics, sound field mapping, acoustic imaging	beamformer, spatial filtering, microphone array, phased array
関連	5	5	5
概要	The Room Impulse Response (RIR) is a measure of how a physical space (room) affects acoustic signals propagating through it. First formalized by Manfred Schroeder in 1965, RIR captures the complete acoustic character of a space by measuring the system response to an impulsive sound source. It is fundamental to characterizing room acoustics, designing audio systems, and modeling spatial audio effects.	Near-Field Acoustic Holography (NAH) is a technique for reconstructing 3D acoustic sound fields and visualizing sound radiation from sources by measuring pressure at a dense microphone array in the near field. Pioneered by Maynard, Williams, and Lee in 1985, NAH extends holographic principles from optics to acoustics, enabling detailed acoustic source characterization, noise source identification, and acoustic field visualization that is impossible with conventional single-point or line-array methods.	Beamforming is a spatial signal processing technique that uses microphone arrays to selectively enhance sound from a desired direction while suppressing sounds from other directions. Formalized by Van Veen and Buckley in 1988, beamforming is fundamental to hands-free speech communication, hearing aids, sonar, radar, and spatial audio recording. It enables 'listening' with directional sensitivity despite using omnidirectional microphones, by exploiting time delays and phase differences between array elements.