Physical Simulation Study of Active Noise Control Up to 5 KHz

Rudd W. Bernie¹, Li Mingfeng¹, Teik C. Lim¹, Jing-Huei Lee²

We demonstrate that active noise control (ANC) is feasible to treat MRI noises at frequencies greater than 2 KHz. Several MRI scan noise and gradient signals were recorded and replayed in a sound quality chamber to simulate the MRI environment. A dummy wore headphones containing piezoceramic speakers with condenser microphones installed inside and outside the earpiece to measure the environmental sound in the immediate patient vicinity. During the simulation study, the sound pressure level (SPL) was measured, both with and without the ANC. Results presented show the ANC system attained significant SPL reduction at all frequencies up to 5 kHz.