Dynamic measurement of room impulse responses using a moving microphone.
A technique for the recording of large sets of room impulse responses or head-related transfer functions is presented. The technique uses a microphone moving with constant speed. Given a setup (e.g., length of the room impulse response), a careful choice of the recording parameters (excitation signal, speed of movement) leads to the reconstruction of all impulse responses along the trajectory. In the case of a moving microphone along a circle, the maximal angular speed is given as a function of the length of the impulse response, its maximal temporal frequency, the speed of sound propagation, and the radius of the circle. As a result of the presented algorithm, head-related transfer functions sampled at 44.1 kHz can be measured at all angular positions along the horizontal plane in less than 1 s. The presented theory is compared with a real system implementation using a precision moving microphone holder. The practical setup is discussed together with its limitations.
Ajdler
Thibaut
T
Audiovisual Communications Laboratory, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland. ajdler@gmail.com
Sbaiz
Luciano
L
Vetterli
Martin
M
D000162:Acoustics; D000465:Algorithms; D000818:Animals; D004455:Echolocation; D005160:Facility Design and Construction; D006257:Head; D006801:Humans; D008954:Models, Biological