04171513 is referenced by 116 patents and cites 6 patents.

A privacy communication system is herein disclosed comprising apparatus for digitizing information to be transmitted, apparatus for logically adding a selected pseudo-random digital code to the digitized information, apparatus for removing the pseudo-random code upon reception and apparatus for synchronizing the transmitted and received pseudo-random codes.

Title
Secure communications system
Application Number
578422
Publication Number
4171513
Application Date
July 22, 1969
Publication Date
October 16, 1979
Inventor
Burton C Winkler Jr
Nashua
NH, US
Charles R Otey
Reeds Ferry
NH, US
Agent
Louis Etlinger
Richard I Seligman
Assignee
Sanders Associates
NH, US
IPC
H04L 9/00
H04K 1/00
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