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:
Feb. 25, 1992
Filed:
Aug. 06, 1990
Applicant:
Inventors:
John R Thompson, La Quinta, CA (US);
C J Hunting, Altadena, CA (US);
William L Phipps, Bermuda Dunes, CA (US);
Steven J Raynesford, Cathedral City, CA (US);
Philip H Rittmueller, St. Charles, IL (US);
Assignee:
NEC Home Electronics, Ltd., Osaka, JP;
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
H04L / ; H04N / ;
U.S. Cl.
CPC ...
380 21 ; 380 10 ; 380 28 ; 380 47 ; 380 45 ;
Abstract
An audiovisual subscription system includes means for aperiodically inverting the lines of a transmitted video signal on a frame-by-frame basis and for decrypting encrypted PCM audio information which is transmitted along with the aperiodically inverted video information.