Transient noise filter employing crosscorrelation to detect noise and autocorrelation to replace the noisey segment
Signal processing system
Time-domain filter for recursive type signals
Adaptive noise cancelling receiver
Multifrequency signal receiving system
Signal correlation means
Receiver device having a function for suppressing transient noises during abrupt interruptions
False alarm processor
High speed digital communication receiver
Waveform synthesizer arrangement
ApplicationNo. 06/373437 filed on 04/30/1982
US Classes:702/193, By threshold comparison327/552, Active filter375/346, Interference or noise reduction455/296, Noise or interference elimination708/300, Filtering708/426Autocorrelation
ExaminersPrimary: Krass, Errol A.
Assistant: Teska, Kevin J.
Attorney, Agent or Firm
International ClassesG10L 21/02 (20060101)
G10L 21/00 (20060101)
H03H 21/00 (20060101)
H04B 14/04 (20060101)
Foreign Application Priority Data1981-05-09 JP
AbstractA noise elimination device employs a concept of the linear prediction method. According to the invention, a linear prediction coefficient of a digitized, continuous input signal (an original signal) is calculated, a linear predicted value is computed from this linear prediction coefficient, difference (a prediction error) between the linear predicted value and the input signal is computed whereas a threshold value is set in accordance with the momentarily changing input signal, the judgement that a noise has occurred is made when the predicted value has exceeded the threshold value and thereupon a substitution signal is produced on the basis of an input signal existing in the vicinity of the time point at which the noise has occurred, and the section in which the noise has occurred is substituted by this substitution signal thereby to eliminate the noise. By virtue of employing the linear prediction method, the necessity for including an error detection code as a part of data has been obviated, the device is made applicable to elimination of a noise contained in an original signal, possibility of making an erroneous judgement has been reduced even with respect to signals having little correlation between themselves by varying the threshold value in accordance with the input signal, and a sufficient noise suppression effect is expected against a burst error or a relatively long noise by producing a substitution signal resembling an input signal on the basis of the input signal containing no noise in the vicinity of the noise section.