Adaptive noise cancellation

E.P.P.A. Derks, B.A. Pauly, J. Jonkers, E.A.H. Timmermans and L.M.C. Buydens, Adaptive noise cancellation on inductively coupled plasma spectroscopy. Chemom. Intell. Lab. Syst., (1998) in press. 

Figure 6.18 Block diagram of an adaptive noise-cancellation system.

The performance of a head-mounted two-microphone adaptive noise-cancellation system was investigated by Weiss [Weiss, 1987] and Schwander and Levitt [Schwander and Levitt, 1987]. In this system, an omnidirectional microphone was used for the speech signal and a rear-facing hypercardioid microphone mounted directly above the speech microphone was used for the noise reference. In a room having a reverberation time of 0.4 sec, this system improved the speech recognition score to 74 percent from 34 percent correct for the unprocessed condition for normal-hearing listeners given... 

Berghe, J.V. and Wouters, J., An adaptive noise canceller for hearing aids using two nearby microphones, The Journal of the Acoustical Society of America, 103,1998, 3621. 

Adaptive noise canceling makes use of an auxiliary or reference input in addition to the noisy signal from the primary sensor. If a reference for the noise is desired, the auxiliary microphone is placed at a position in the noise field where the signal is weak or undetectable. This scheme operates on the basis of two main assumptions ... 

The earKest work on adaptive noise cancelers can be traced to the mid 1960s to Kelly of Bell Telephone Laboratories, who first proposed the use of an adaptive filter for echo cancellation of speech signals. Kelly s contribution is cited in the bookby Haykin (1991). Widrow et al. (1975) extended the concept and built a device to cancel 60-Hz interference at the output of an electrocardiograph amplifier and recorder. Lim and Oppenheim (1979) discuss the use of adaptive noise cancellation on speech and find that, at some SNR, the technique actually decreases the intelligibility of the speech signal. 

Zahedi, E. Gan. K.B. 2008. Applicability of adaptive noise cancellation to fetal heart rate detection using photi lethysmography. Comput. Biol. Med. 38 31-41... 

Mylonas, S.A, Trancoso, P. and Trimikliniotis, M. (2000) Adaptive Noise canceling and Edge Detection in Images using PVM on a NOW. 10th Mediterranen Electrotechnical Conference. 

Removing Noise and Artifacts from EEG Using Adaptive Noise Cancelator and... 

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