Noise Cancellation Techniques for Enhancing Speech Communication in Mechanized Mines

Abstract

Active Noise Cancellation is an approach to noise reduction in which a secondary noise source that destructively interferes with the unwanted noise is introduced. Unwanted acoustic noise is a by-product of many industrial processes and systems including Surface and Underground mines. The sound level inside the mines are beyond permissible level at most of the places and a solution to it using conventional headphones has failed because of its inefficiency in allowing desirable sounds of person to person communication and the sound of the alarm of the ‘Roof Fall’. This paper illustrates a design of special headphone incorporating the techniques of ANC and Band Pass Filters for use in mechanized mines which allows all the desirable sound to pass through but filters out the undesired machine noise.