Diagnostic device including a method and apparatus for bio-potential noise cancellation utilizing the patient's respiratory signal

A diagnostic medical imaging device including a signal processor that includes an adaptive filter noise canceler that is used to reduce the additive electrical noise on low power bio-potential signals caused by a patient's respiration. A noise reference signal associated with the patient's respiration is adaptively filtered with only minimal time delay and subtracted from a noisy bio-potential signal that is acquired from the patient. The resultant signal is a clean bio-potential signal that may be used for, among other things, triggering an MRI scan. The noise reference signal is received by an adaptive filter having adjustable filter coefficients. The filter coefficients are adjusted using the clean bio-potential signal that acts an error signal.