Delay based active noise cancellation for magnetic resonance imaging

摘要

System and method for actively canceling the acoustic noise generated by changes in the electric current within the gradient coils of a magnetic resonance imager based on the finding that the acoustic noise in the magnetic resonance imager is highly periodic but that the period of the magnetic resonance imager noise changes substantially during a scan. The acoustic noise signal is measured at the ears of a patient undergoing a magnetic resonance imaging, delayed by a variable number of samples and the resulting signal is subtracted from the acoustic noise signal. Magnetic resonance imaging noise cancellation occurs at the level of 20 decibels or more.