Acoustic noise cancellation in a multiple noise source environment

A multireference adaptive noise canceller (MRANC) is derived from an analysis of a multiple-noise-source acoustic environment. The approach places a microphone near each noise source and one microphone near the speech source. Each noise reference microphone receives a signal primarily from its associated noise source along with contributions from other sources. This is called coupling, which degrades the MRANC performance under certain circumstances. The optimal noise cancelling structure is determined. From this optimal filter structure, several filter structures for processing the reference signals are derived based on assumptions about the environment. Quantitative test results from real-life environments are presented and discussed.<>