Development of a digital goniometer

Abstract

Quality measurements of sound diffraction and diffusion patterns can be achieved utilizing a circular array of microphones, known as an acoustical goniometer. The analog electret microphones that have been used in previous designs have performed well, typically recording signal to noise ratios in the mid 60 decibels, but noise interference in the signals results in data from certain areas of the circular array being too obscured to be useful, resulting in shadow zones. With the design of a new goniometer using digital PDM microphones, the signal-to-noise ratio should be greatly improved. By exploring new technology and using it to upgrade the current measurement apparatuses this work can advance the acoustic measurement of sound diffraction patterns.