This paper describes the concept of adaptive noise cancelling, an alternative method of estimating signals corrupted by additive noise or interference. The method uses a "primary" input containing the corrupted signal and a "reference" input containing noise correlated in some unknown way with the primary noise. The reference input is adaptively filtered and subtracted from the primary input to obtain the signal estimate. Adaptive filtering before subtraction allows the treatment of inputs that are deterministic or stochastic, stationary or time variable. Wiener solutions are developed to describe asymptotic adaptive performance and output signal-to-noise ratio for stationary stochastic inputs, including single and multiple reference inputs. These solutions show that when the reference input is free of signal and certain other conditions are met noise in the primary input can be essentiany eliminated without signal distortion. It is further shown that in treating periodic interference the adaptive noise canceller acts as a notch filter with narrow bandwidth, infinite null, and the capability of tracking the exact frequency of the interference; in this case the canceller behaves as a linear, time-invariant system, with the adaptive filter converging on a dynamic rather than a static solution. Experimental results are presented that illustrate the usefulness of the adaptive noise cancelling technique in a variety of practical applications. These applications include the cancelling of various forms of periodic interference in electrocardiography, the cancelling of periodic interference in speech signals, and the cancelling of broad-band interference in the side-lobes of an antenna array. In further experiments it is shown that a sine wave and Gaussian noise can be separated by using a reference input that is a delayed version of the primary input. Suggested applications include the elimination of tape hum or turntable rumble during the playback of recorded broad-band signals and the automatic detection of very-low-level periodic signals masked by broad-band noise.

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Adaptive noise cancelling: Principles and applications

Institutional Affiliations Chair Costanzo MR: Midwest Heart Foundation, Lombard Illinois, USA Task Force 1 Dipchand A: Hospital for Sick Children, Toronto Ontario, Canada; Starling R: Cleveland Clinic Foundation, Cleveland, Ohio, USA; Anderson A: University of Chicago, Chicago, Illinois, USA; Chan M: University of Alberta, Edmonton, Alberta, Canada; Desai S: Inova Fairfax Hospital, Fairfax, Virginia, USA; Fedson S: University of Chicago, Chicago, Illinois, USA; Fisher P: Ochsner Clinic, New Orleans, Louisiana, USA; Gonzales-Stawinski G: Cleveland Clinic Foundation, Cleveland, Ohio, USA; Martinelli L: Ospedale Niguarda, Milano, Italy; McGiffin D: University of Alabama, Birmingham, Alabama, USA; Parisi F: Ospedale Pediatrico Bambino Gesu, Rome, Italy; Smith J: Freeman Hospital, Newcastle upon Tyne, UK Task Force 2 Taylor D: Cleveland Clinic Foundation, Cleveland, Ohio, USA; Meiser B: University of Munich/Grosshaden, Munich, Germany; Baran D: Newark Beth Israel Medical Center, Newark, New Jersey, USA; Carboni M: Duke University Medical Center, Durham, North Carolina, USA; Dengler T: University of Hidelberg, Heidelberg, Germany; Feldman D: Minneapolis Heart Institute, Minneapolis, Minnesota, USA; Frigerio M: Ospedale Niguarda, Milano, Italy; Kfoury A: Intermountain Medical Center, Murray, Utah, USA; Kim D: University of Alberta, Edmonton, Alberta, Canada; Kobashigawa J: Cedar-Sinai Heart Institute, Los Angeles, California, USA; Shullo M: University of Pittsburgh, Pittsburgh, Pennsylvania, USA; Stehlik J: University of Utah, Salt Lake City, Utah, USA; Teuteberg J: University of Pittsburgh, Pittsburgh, Pennsylvania, USA; Uber P: University of Maryland, Baltimore, Maryland, USA; Zuckermann A: University of Vienna, Vienna, Austria. Task Force 3 Hunt S: Stanford University, Palo Alto, California, USA; Burch M: Great Ormond Street Hospital, London, UK; Bhat G: Advocate Christ Medical Center, Oak Lawn, Illinois, USA; Canter C: St. Louis Children Hospital, St. Louis, Missouri, USA; Chinnock R: Loma Linda University Children's Hospital, Loma Linda, California, USA; Crespo-Leiro M: Hospital Universitario A Coruna, La Coruna, Spain; Delgado R: Texas Heart Institute, Houston, Texas, USA; Dobbels F: Katholieke Universiteit Leuven, Leuven, Belgium; Grady K: Northwestern University, Chicago, Illlinois, USA; Kao W: University of Wisconsin, Madison Wisconsin, USA; Lamour J: Montefiore Medical Center, New York, New York, USA; Parry G: Freeman Hospital, Newcastle upon Tyne, UK; Patel J: Cedar-Sinai Heart Institute, Los Angeles, California, USA; Pini D: Istituto Clinico Humanitas, Rozzano, Italy; Pinney S: Mount Sinai Medical Center, New York, New York, USA; Towbin J: Cincinnati Children's Hospital, Cincinnati, Ohio, USA; Wolfel G: University of Colorado, Denver, Colorado, USA Independent Reviewers Delgado D: University of Toronto, Toronto, Ontario, Canada; Eisen H: Drexler University College of Medicine, Philadelphia, Pennsylvania, USA; Goldberg L: University of Pennsylvania, Philadelphia, Pennsylvania, USA; Hosenpud J: Mayo Clinic, Jacksonville, Florida, USA; Johnson M: University of Wisconsin, Madison, Wisconsin, USA; Keogh A: St Vincent Hospital, Sidney, New South Wales, Australia; Lewis C: Papworth Hospital Cambridge, UK; O'Connell J: St. Joseph Hospital, Atlanta, Georgia, USA; Rogers J: Duke University Medical Center, Durham, North Carolina, USA; Ross H: University of Toronto, Toronto, Ontario, Canada; Russell S: Johns Hopkins Hospital, Baltimore, Maryland, USA; Vanhaecke J: University Hospital Gasthuisberg, Leuven, Belgium.

http://www.jsht.jp/uploads/ISHLT_GL_TaskForce2_110810.pdf

Richard R. Lower

Papers

Studies on orthotopic homotransplantation of the canine heart.

Homovital transplantation of the heart.

Homovital transplantation of the heart

Transplantation of the heart.

Selective hypothermia of the heart in anoxic cardiac arrest.