JPS5660138A - Secret transmission system for digitized sound signal - Google Patents

Secret transmission system for digitized sound signal

Info

Publication number
JPS5660138A
JPS5660138A JP13662179A JP13662179A JPS5660138A JP S5660138 A JPS5660138 A JP S5660138A JP 13662179 A JP13662179 A JP 13662179A JP 13662179 A JP13662179 A JP 13662179A JP S5660138 A JPS5660138 A JP S5660138A
Authority
JP
Japan
Prior art keywords
code string
gate
waveform
circuit
random
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.)
Granted
Application number
JP13662179A
Other languages
Japanese (ja)
Other versions
JPS6036665B2 (en
Inventor
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 JP54136621A priority Critical patent/JPS6036665B2/en
Publication of JPS5660138A publication Critical patent/JPS5660138A/en
Publication of JPS6036665B2 publication Critical patent/JPS6036665B2/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04K—SECRET COMMUNICATION; JAMMING OF COMMUNICATION
    • H04K1/00—Secret communication
    • H04K1/02—Secret communication by adding a second signal to make the desired signal unintelligible

Landscapes

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

Abstract

PURPOSE:To secure secrecy sufficiently by simple constitution by inverting and transmitting part of a bit value, i.e. the most significant digit bit or uppermost bit, constituting a digitized sound signal, according to a random-number code string. CONSTITUTION:Fundamental-tone signal waveform (a), supplied to input terminal 1, is applied to pulse code moculating circuit 2 and sampled by sampling pulse of a constant period, so that binary codes shown by waveform (b) will be outputted at intervals of sampling. The output of this circuit 2 is applied to one input of exclusive OR gate 3 and a random-number code string, shown by waveform (c), generated by random number generator 4 is also applied to the other input of this gate 3 to invert bits, indicated by mark , in the code string. Then, gate 3 outputs the value of the binary code string from circuit 2 as it is when the code string is 0 or inverts and outputs the value when 1 to generate an output of waveform (d) of gate 3, which is sent out via transmitting circuit 5, no that the secrecy can be secured sufficiently in the simple method.
JP54136621A 1979-10-23 1979-10-23 Secret transmission method for digitized audio signals Expired JPS6036665B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP54136621A JPS6036665B2 (en) 1979-10-23 1979-10-23 Secret transmission method for digitized audio signals

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP54136621A JPS6036665B2 (en) 1979-10-23 1979-10-23 Secret transmission method for digitized audio signals

Publications (2)

Publication Number Publication Date
JPS5660138A true JPS5660138A (en) 1981-05-23
JPS6036665B2 JPS6036665B2 (en) 1985-08-21

Family

ID=15179577

Family Applications (1)

Application Number Title Priority Date Filing Date
JP54136621A Expired JPS6036665B2 (en) 1979-10-23 1979-10-23 Secret transmission method for digitized audio signals

Country Status (1)

Country Link
JP (1) JPS6036665B2 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58153435A (en) * 1982-03-08 1983-09-12 Toshiba Corp Transmitting device of voice security
JPS62290223A (en) * 1986-06-10 1987-12-17 Pioneer Answerphone Mfg Corp Scramble/descramble system for narrow band transmission system
JPS62290225A (en) * 1986-06-10 1987-12-17 Pioneer Answerphone Mfg Corp Scramble/descramble system for narrow band transmission system

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58153435A (en) * 1982-03-08 1983-09-12 Toshiba Corp Transmitting device of voice security
JPS62290223A (en) * 1986-06-10 1987-12-17 Pioneer Answerphone Mfg Corp Scramble/descramble system for narrow band transmission system
JPS62290225A (en) * 1986-06-10 1987-12-17 Pioneer Answerphone Mfg Corp Scramble/descramble system for narrow band transmission system

Also Published As

Publication number Publication date
JPS6036665B2 (en) 1985-08-21

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