Abstract A feature recognition system for extracting transient signal information from a signal-like noise background by separating a time domain signal into a plurality of frequency-time domain signals by frequency selective filters. Each of the filtered outputs is converted to unidirectional signals and then displayed on a chart recorder from which the presence of a signal is determined on the basis of one or more of three criteria. The first criteria is maximum energy in a predetermined one of the selected frequencies; the second criteria is the time convergence of the time-tracings of peaks and troughs of the unidirectional signal lobes at the higher frequencies; and the third criteria is the difference in shape factors for sgnal information as opposed to noise information.
Inventors
👤 M Bobrin
Bibliographic Details
Application Number—
JurisdictionUS
Data Sourcegoogle_patents
Last Synchronized2026-11-05 10:25
CPC Classifications
G; G01; G01V; G01V3/00; G01V3/08
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
188 words
An apparatus for detecting submarine signatures in a signallike noise background (as recited in claim 3 wherein said plurality of low-Q band pass filters further comprises) comprising: means for receiving magnetic anomaly detection signals in the time-domain, said means including a magnetic anomaly detector for detecting variations in the earth''s magnetic field caused by the presence of a submarine; separator means electrically connected to said detector means for separating said signals into preselected frequency components, said separator means including a plurality of low-Q band pass filters having their inputs connected to said magnetic anomaly detector for separating said signals in the time-domain into preselected frequency components in the frequency-time domain, said plurality of (seven) band pass filters having center frequencies substantially of 0.048 cycles per second, 0.075 cycles per second, 0.12 cycles per second, 0.19 cycles per second, 0.30 cycles per second, 0.48 cycles per second and 0.75 cycles per second(.); converter means connected to the outputs of each of said filters for converting said frequency components into signals having unidirectional lobes; and display means operatively connected to said converter means for displaying said signals having unidirectional lobes.