05629739 is referenced by 160 patents and cites 8 patents.

An ancillary signal is injected into a program signal within the frequency band normally occupied by the program signal alone. The program signal includes a modulated carrier having a carrier frequency and a low energy density portion of the frequency band. The ancillary signal is selectively added at an injection frequency within the lower energy density portion of the frequency band so that the injection frequency is locked to the carrier frequency and to the frequency of a local oscillator.

Title
Apparatus and method for injecting an ancillary signal into a low energy density portion of a color television frequency spectrum
Application Number
8/399187
Publication Number
5629739
Application Date
March 6, 1995
Publication Date
May 13, 1997
Inventor
Robert A Dougherty
Ozona
FL, US
Agent
Marshall O Toole Gerstein Murray & Borun
Assignee
A C Nielsen Company
IL, US
IPC
H04N 7/00
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