JPS54129902A - Secret communication system - Google Patents

Secret communication system

Info

Publication number
JPS54129902A
JPS54129902A JP3774678A JP3774678A JPS54129902A JP S54129902 A JPS54129902 A JP S54129902A JP 3774678 A JP3774678 A JP 3774678A JP 3774678 A JP3774678 A JP 3774678A JP S54129902 A JPS54129902 A JP S54129902A
Authority
JP
Japan
Prior art keywords
communication
secret
signal
synchronizing signal
sound signal
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP3774678A
Other languages
Japanese (ja)
Inventor
Shigeru Asakawa
Makoto Nakamura
Fumio Sugiyama
Tsukasa Okai
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Toshiba Corp
Original Assignee
Toshiba Corp
Tokyo Shibaura Electric Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Toshiba Corp, Tokyo Shibaura Electric Co Ltd filed Critical Toshiba Corp
Priority to JP3774678A priority Critical patent/JPS54129902A/en
Publication of JPS54129902A publication Critical patent/JPS54129902A/en
Pending legal-status Critical Current

Links

Abstract

PURPOSE: To exercise high-articulation communication by preventing the mixture of an impulsive noise due to the turning around of a synchronizing signal after securing sufficiently the secret of communication by transmitting the synchronizing signal via a two-wire line such as a telephone circuit together with a sound signal made into secret-communication information.
CONSTITUTION: Telephone set 11 is connected to telephone circuit 14 via switch circuits 12 and 13 interlocking together, and secret-communication device 15 is separated into two systems, the transmission side and reception side, via circuits 12 and 13. At the transmission side, a sound signal from hybrid coil 17 is inputted to secret-communication processing circuit 18 and the signal received via hybrid coil 16 after the fixed secret-communication process is inputted to secret-communication reload circuit 19, where it is changed into the original signal. Consequently, the synchronizing signal is transmitted via the two-wire line such as a telephone circuit together with the sound signal made into secret-communication information, and the mixture of an impulsive noise, etc., due to the turning around of the synchronizing signal is prevented besides securing the secret of the communication, so that high-articulation communication can be fulfilled.
COPYRIGHT: (C)1979,JPO&Japio
JP3774678A 1978-03-31 1978-03-31 Secret communication system Pending JPS54129902A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP3774678A JPS54129902A (en) 1978-03-31 1978-03-31 Secret communication system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP3774678A JPS54129902A (en) 1978-03-31 1978-03-31 Secret communication system

Publications (1)

Publication Number Publication Date
JPS54129902A true JPS54129902A (en) 1979-10-08

Family

ID=12506035

Family Applications (1)

Application Number Title Priority Date Filing Date
JP3774678A Pending JPS54129902A (en) 1978-03-31 1978-03-31 Secret communication system

Country Status (1)

Country Link
JP (1) JPS54129902A (en)

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