04145568 is referenced by 45 patents.

Method and apparatus for ciphering and deciphering messages, wherein series of cipher pulses with an identical pulse distribution are generated by the transmitter and the receiver stations and said pulse distribution is determined by a secret basic code and a code which is derived from date and time.

Title
Method and apparatus for ciphering and deciphering messages
Application Number
5/401795
Publication Number
4145568
Application Date
October 6, 1964
Publication Date
March 20, 1979
Inventor
Kurt Ehrat
Zurich
CH
Agent
Burns Doane Swecker & Mathis
Assignee
Gretag Aktiengesellschaft
CH
IPC
H04L 9/02
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