Patent ID: 7286871

Claim:
A method of reducing contamination of electrical signals recorded in the presence of repeated interference contamination comprising: (a) obtaining an electrical signal, wherein the electrical signal was recorded in the presence of a contaminating signal; (b) detecting a timing signal that occurs at a fixed time point during the electrical signal relative to the onset of the contaminating signal; (c) digitizing the electrical signal, wherein the digitizing begins with the timing signal; (d) analyzing a plurality of digitized electrical signals, wherein the electrical signals are synchronized with respect to the timing signal, to obtain an estimated contaminating signal; and (e) subtracting the estimated contaminating signal from the digitized electrical signal, thereby reducing contamination of the electrical signal; wherein the analyzing to obtain the estimate of the contaminating signal comprises calculating a weighted average of the contaminating signals; and wherein the estimate of the contaminating signal is biased towards recent events, and comprises a first sum consisting of the nth electrical signal added to a scalar multiple, w, of a prior estimate of the contaminating signal, divided by a second sum obtained by adding a series 1+w2+w3+w4 . . . + . . . wn.