04308614 is referenced by 90 patents and cites 6 patents.

This invention provides means and method of eliminating a selected wave from a frequency band containing a plurality of waves, by sampling the plurality of waves at a rate greater than the nyquist rate for the frequency band in herz, at instants at which the selected wave has zero amplitude, and integrating the sequence of samples so obtained to produce a replica of the plurality of waves less the selected wave.

The plurality of waves less the selected wave may be subtracted from the plurality of waves, after adjustment of relative amplitude and delay, so that the selected wave is obtained substantially free of other waves of the plurality of waves.

Thus a selected undesired wave, with a maximum period between successive instants of zero amplitude of less than the nyquist interval for the frequency band, may be substantially eliminated without affecting other waves; a selected desired wave, with a maximum period between successive instants of zero amplitude of one-half the period of the bandwidth of the frequency band, may be recovered substantially free from noise.

Title
Noise-reduction sampling system
Application Number
5/955153
Publication Number
4308614
Application Date
October 26, 1978
Publication Date
December 29, 1981
Inventor
Sidney T Fisher
53 Morrison Ave., Mt. Royal, H3R 1K3, Quebec
CA
Charles B Fisher
2850 Hill Park Rd., Montreal, H3H 1T1
CA
IPC
H04J 15/00
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