Parameterization of the three-dimensional room transfer function in horizontal plane

Abstract

This letter proposes an efficient parameterization of the three-dimensional room transfer function (RTF) which is robust for the position variations of source and receiver in respective horizontal planes. Based on azimuth harmonic analysis, the proposed method exploits the underlying properties of the associated Legendre functions to remove a portion of the spherical harmonic coefficients of RTF which have no contribution in the horizontal plane. This reduction leads to a flexible measuring-point structure consisting of practical concentric circular arrays to extract horizontal plane RTF coefficients. The accuracy of the above parameterization is verified through numerical simulations.

Extraction of exterior field from a mixed sound field for 2D height-invariant sound propagation

“…Also, in the case of a 3D sound field, the proposed method requires minimum (ker 2 + 1) 2 /(A + 1) 2 of A th order microphones to sample the sound field [5]. The number can be reduced if we consider the reflections from XY plane only (e.g., no reflection from ceiling or floor) [16].…”

Deep Learning-Based Estimation of Reverberant Environment for Audio Data Augmentation

“…The reverberation environment of a room is estimated by modeling the sound transmission process. The conventional estimation methods use the room impulse response (RIR) [7][8][9] or room transfer function (RTF) [10,11], and convolve RIR and clean sound to create a virtual reverberant sound in a specific space. Among recent studies, there is a study of learning an artificial neural network using the structure of a room and acoustic signals acquired from the room, where RT60, which is an attenuation parameter of the sound pressure level, was estimated and used to construct a reverberant signal [12].…”

Reproduction of Nearby Sound Sources Using a Modified Distance Coding in Higher Order Ambisonics

“…(2) By using the addition theorem of cylindrical harmonics [11][12], the multi-frequency sound field can be rewritten as: The equation (3) have an infinite number of orthogonal modes, which is not possible to be achieved, therefore this series expansion can be truncated to a finite number due to the properties of the Bessel function within the region of interest which is a circular region of radius l r (  l rr ). Hence, (3) can be truncated to M terms as:…”