Generating acoustic quiet zone by noise injection techniques

Abstract

A system for generating and injecting acoustic interference signals to mitigate undesired acoustic noise over a target zone. M pickup sensors pick up acoustic noise signals from one or more noise sources in real time and generate M noise signals, M>1. A beam forming network includes M acoustic beam forming modules to process the M noise signals respectively and generate N acoustic interference signals. N acoustic injectors condition, amplify and inject the N acoustic interference signals over the target zone, N>1. Each of the M acoustic beam forming modules includes a 1-to-N distribution network to transform a respective one of the M noise signals into N signals, and N finite-impulse-response filters to perform amplitude and phase weighting on the respective N signals and generate N intermediate signals which are combined respectively with corresponding intermediate signals generated by remaining M−1 acoustic beam forming modules to generate the N acoustic interference signals.