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:
Sep. 04, 1990
Filed:
Mar. 13, 1989
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
In a method for multiplexing the transmission of audio and video signals, the video signal is separated into a luminance signal and a chrominance signal. The luminance signal is then modulated, and the chrominance signal is balanced-modulated with a low-frequency carrier. The chrominance signal is then converted to a lower frequency. The audio signal, frequency-modulated luminance signal and frequency-converted chrominance signal and frequency-converted chrominance signal are multiplexed by frequency division to be transmitted across telephone cable. Consequently, in comparison with the conventional transmission method which executes direct frequency modulation of the video signal, the band-width of the frequency-modulated luminance signal becomes narrower to eventually facilitate multichannel transmission. The harmful influence from interference from external radio waves or from metallic members used to fix the cable is removed on the receiver side. Accordingly, satisfactory picture transmission can be performed without the necessity of any additional coaxial cable for video signal transmission.