The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 13, 1983
Filed:
May. 18, 1981
David B Francis, Mount Kisco, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
An apparatus and method for removing signal frequency sinusoidal noise from an analog signal is disclosed. The filter apparatus utilizes A Programmable Gain Amplifier (PGA) as an input to a discrete sine wave generator to control the amplitude and phase of the discrete sine wave generator. The output of the latter, after being full live rectified, controls the gain of the PGA so that its output, when appropriately phase shifted, cancels sinusoidal noise from a sampled analog signal. The apparatus is particularly adapted to cancelling 60 cycle noise from electrocardiogram (ECG) signals. The filtering approach can be implemented on a programmed general purpose digital computer and the method steps for achieving filtering of single frequency noise from an analog signal are disclosed.