Active acoustic echo compensation, by generating acoustic signal with 180 degree phase shift to cancel incident acoustic signal at boundary surface

摘要

A sound source is placed at a boundary surface and generates an acoustic signal corresponding to the incident acoustic signal, but with a 180 degree phase shift, so that the two events cancel each other out near to the boundary surface, preventing the occurrence of echoes caused by reflection at the boundary surface. Several sound sources may be used, and excited with similar or different signals, to eliminate acoustic events at the boundary surface.