05216713 is referenced by 16 patents and cites 7 patents.

In a extraneous of signal method of preventing detection of signal information from raster scan signals in a plurality of consecutive line signals intended to form an image or partial images there is generated a random signal sequence, correlated with the information-carrying raster scan signals, but without information content, which is transmitted as protection for the raster scan signals. An apparatus for this purpose includes a generator (10,12) adapted for generating a random signal sequence synchronous with the raster scan signals, and a switching element (5) adapted to transmit the random signal sequence round the equipment containing the raster scan signals that are to be protected.

Title
Method and apparatus for preventing extraneous detection of signal information
Application Number
7/824093
Publication Number
5216713
Application Date
January 22, 1992
Publication Date
June 1, 1993
Inventor
Per Lindholm
Stockholm
SE
Agent
Oblon Spivak McClelland Maier & Neustadt
Assignee
Shield Research in Sweden
SE
IPC
H04N 1/02
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