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:
Dec. 25, 1990
Filed:
Oct. 13, 1988
Applicant:
Inventors:
Gerald R Newell, Alamo, CA (US);
Pradeep Bhardwaj, Concord, CA (US);
Assignee:
Systron Donner, Concord, CA (US);
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H03M / ;
U.S. Cl.
CPC ...
341157 ; 329323 ; 375 53 ; 341 50 ;
Abstract
An analog baseband signal modulates a reference-frequency carrier signal to provide a double-sideband, suppressed-carrier DSB-SC signal. The DSB-SC signal is converted in a voltage-to-frequency converter to a series of pulses, which are demodulated to produce a digitally formatted version of the baseband signal. A notch filter for rejecting an undesired analog signal includes a voltage-to-frequency converter and a selective feedback path which demodulates the undesired signal from a frequency-encoded domain back to the analog domain for a cancellation in a summer preceding the voltage-to-frequency converter.