JPS5526728A - Secret communication unit - Google Patents

Secret communication unit

Info

Publication number
JPS5526728A
JPS5526728A JP9928078A JP9928078A JPS5526728A JP S5526728 A JPS5526728 A JP S5526728A JP 9928078 A JP9928078 A JP 9928078A JP 9928078 A JP9928078 A JP 9928078A JP S5526728 A JPS5526728 A JP S5526728A
Authority
JP
Japan
Prior art keywords
secret
sound signal
signal
period
sound
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
JP9928078A
Other languages
Japanese (ja)
Inventor
Tsukasa Okai
Makoto Nakamura
Fumio Sugiyama
Shigeru Asakawa
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 JP9928078A priority Critical patent/JPS5526728A/en
Publication of JPS5526728A publication Critical patent/JPS5526728A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04K—SECRET COMMUNICATION; JAMMING OF COMMUNICATION
    • H04K1/00—Secret communication

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)

Abstract

PURPOSE:To secure sufficiently secrecy by preventing a unit from getting out of synchronism due to a turnaround, by attaining synchronization by extracting synchronous information from an input secret signal. CONSTITUTION:The input period of a sound signal to be sent out is detected by sound detection circuit 8; only during the sound input period, analog switch 9a is turned ON to send out a secret sound signal with an additional synchronizing signal and in this transmission period, analog switch 9b is turned ON to stop the reception of the secret sound signal. In a period except the sound input period, switch 9a is OFF with switch 9b ON so as to receive the secret sound signal from other stations without sending the secret sound signal of its own out. Consequently, no turnaround of its own signal occurs in the reception of the secret sound signal and the excellent secret sound signal with its period stabilized can be restored.
JP9928078A 1978-08-15 1978-08-15 Secret communication unit Pending JPS5526728A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP9928078A JPS5526728A (en) 1978-08-15 1978-08-15 Secret communication unit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP9928078A JPS5526728A (en) 1978-08-15 1978-08-15 Secret communication unit

Publications (1)

Publication Number Publication Date
JPS5526728A true JPS5526728A (en) 1980-02-26

Family

ID=14243242

Family Applications (1)

Application Number Title Priority Date Filing Date
JP9928078A Pending JPS5526728A (en) 1978-08-15 1978-08-15 Secret communication unit

Country Status (1)

Country Link
JP (1) JPS5526728A (en)

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