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. 19, 1989
Filed:
Dec. 13, 1985
Guy B Coleman, Northridge, CA (US);
James W Henderson, Woodland Hills, CA (US);
Jack Sacks, Thousand Oaks, CA (US);
Multilink Group, Calabasas, CA (US);
Abstract
A multiplexer for compressing two television programs into the bandwidth normally required for a single television signal is disclosed wherein vertically adjacent lines in the odd and even field of each frame are summed and differenced in pairs having the same color subcarrier phase. 'Line pair signals' respectively comprising the sum and difference of each line pair are then formed after the difference signal is time compressed without an overall increase in bandwdth. The line pair signals for each frame of one program are alternately transmitted with the line pair signals of a frame from the second program. The line pair signals of a video frame are fewer in number and longer in duration than NTSC field lines. Timing is such that one frame of both programs is transmitted during the time allotted to the transmission of one frame under the NTSC standard. The lines from odd fields of each program are reconstructed after transmission by adding the appropriate difference signals and sum signals. The lines from even fields are reconstructed by differencing the sum signals and the difference signals.