The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 26, 1977
Filed:
Feb. 23, 1976
James R Van Cleave, Furlong, PA (US);
American Electronic Laboratories, Inc., Colmar, PA (US);
Abstract
A signal processing means and method of adaptively filtering input signals received at a terminal means in which the input signals include pulse signals and noise, with the pulse signals occurring at unknown times and having unknown durations, which includes signal filtering means having a first input for receiving signals derived from the terminal means, a second input and an output, the signal filtering means having a controllable filter characteristic for passing signals from its first input to its output responsive to signals received at its second input, and a signal analyzing means having an input receiving signals derived from said terminal means and an output delivering signals which are responsive to signals received at its input, to the second input of said signal filtering means for controlling its filter characteristic, whereby the output of the signal filtering means delivers signals corresponding to the pulse signals of the input signals to said terminal means while minimizing delivery of noise signals received at said terminal means. The means and method utilizes orthogonal transformations of the input signals for processing the input signals and adaptively filtering the orthogonal signal components for providing at the output, pulse signals present in the input signal with reduction in the noise level. Walsh functions are utilized for filtering rectangular pulse signals while other orthogonal functions, including Fourier functions, are utilized for filtering non-rectangular pulse signals. The incoming signals are preferably converted to digital form and transformed by the orthogonal functions for adaptive filtering, after which the signals may be reconverted by an inverse transformation and delivered in digital or analog form. Rectangular pulse signals after being transformed back into the time domain, are further reconstructed by a thresholding operation providing the original DC level for the signal, together with the rectangular signals determined by the means and method of the invention to be present in the input signal.