Accession Number : ADD014179

Title :   Multi-Stage Noise-Reducing System.

Descriptive Note : Patent Application, Filed 20 Mar 89,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s) : Miller, Harry B

Report Date : 20 Mar 1989

Pagination or Media Count : 29

Abstract : An electronic noise-reducing system which includes a plurality of adaptive filters forming multiple stages of noise reduction and producing greatly increased signal-to-noise ratio. The input for the primary channel of the first adaptive filter, which forms the first noise-reducing stage, is the signal including multitones buried in noise. The reference channel ideally uses signal-free noise as input. The output of the first adaptive filter is used as the input to the primary channel of the second or final adaptive filter, whereas the reference channel thereof is fed with 'clean noise'. The clean noise can be obtained as the output of the intermediate adaptive filter by feeding simultaneously both the primary and reference channels of the intermediate filter with the noise-reduced waveform present at the output of the first noise-reducing filter. Patent applications. (RH)

Descriptors :   *ADAPTIVE FILTERS, *CHANNELS, *NOISE, *NOISE REDUCTION, *PATENT APPLICATIONS, *SIGNAL TO NOISE RATIO, FILTERS, WAVEFORMS

Subject Categories : Cybernetics
      Electrical and Electronic Equipment

Distribution Statement : APPROVED FOR PUBLIC RELEASE