05087970 is referenced by 3 patents and cites 3 patents.

A high definition television system to provide an efficient use of bandwidths, derives from a high definition television source signal, composite main signals and composite line differential signals. These signals are divided into main center components and main panel components and line differential center components and line differential panel components. The line differential center components and main center components are then quadrature modulated and transmitted as a vestigial sideband signal over a first transmission path. The main panel components and the line differential panel components are quadrature modulated and formed into a vestigial sideband signal which is then time multiplexed with the high frequency luminance signal forming a time multiplexed signal. The time multiplexed signal is then frequency multiplexed with a digital sound and synchronization signal in order to form an augmentation signal which is transmitted over a portion of a second transmission path.

Title
System for providing a high definition television (HDTV) augmentation channel comprising time and frequency multiplexed components
Application Number
239148
Publication Number
5087970
Application Date
June 22, 1990
Publication Date
February 11, 1992
Inventor
Mikhail Tsinberg
Riverdale
NY, US
Karl Wittig
New York
NY, US
Alan P Cavallerano
Ossining
NY, US
Agent
Michael E Marion
Assignee
North American Philips Corporation
NY, US
IPC
H04N 7/04
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