METHOD AND APPARATUS FOR PROCESSING SIGNALS OF A SPHERICAL MICROPHONE ARRAY ON A RIGID SPHERE USED FOR GENERATING AN AMBISONICS REPRESENTATION OF THE SOUND FIELD

摘要

Spherical microphone arrays are represented by Ambisonics ( A three-dimensional sound field (" Where the pressure distribution on the surface of the sphere is sampled by the capsules of the array. The effect of the microphone on the captured sound field is removed using an inverse microphone transfer function. Equalization of the transfer function of the microphone array is a big problem because the inverse of the transfer function results in high gain for small values in the transfer function and these small values are affected by the transducer noise. The present invention estimates (73) the signal-to-noise ratio between the noise power from the microphone array capsules and the average sound field power, calculates (74) the average spatial signal power at the origin for the diffuse sound field, The frequency response of the equalization filter is designed in the frequency domain from the power and the square root of the fraction of the simulated power at the origin.