JPS57111150A - Radio communication system - Google Patents

Radio communication system

Info

Publication number
JPS57111150A
JPS57111150A JP18691480A JP18691480A JPS57111150A JP S57111150 A JPS57111150 A JP S57111150A JP 18691480 A JP18691480 A JP 18691480A JP 18691480 A JP18691480 A JP 18691480A JP S57111150 A JPS57111150 A JP S57111150A
Authority
JP
Japan
Prior art keywords
varied
detector
frequency
signal
inputted
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
JP18691480A
Other languages
Japanese (ja)
Inventor
Misao Kikuchi
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.)
Fujitsu Ltd
Original Assignee
Fujitsu 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 Fujitsu Ltd filed Critical Fujitsu Ltd
Priority to JP18691480A priority Critical patent/JPS57111150A/en
Publication of JPS57111150A publication Critical patent/JPS57111150A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04K—SECRET COMMUNICATION; JAMMING OF COMMUNICATION
    • H04K1/00—Secret communication
    • H04K1/003—Secret communication by varying carrier frequency at or within predetermined or random intervals

Abstract

PURPOSE:To prevent interception, by executing the transmission and receiving by a communcation frequency which is varied in accordance with a designated program by both the transmission side and the receiving side. CONSTITUTION:The transmission side mixes a base band signal from a signal source 1 and a carrier wave from a cystal oscillator 8 after transmitting a routine access signal, and transmits a signal whose frequency is varied, from an antenna 21 through multiplying equipments 4, 5 and an amplifier 6. On the other hand, in the receiving side, since oscillation frequency of a local oscillator 14 is varied, output frequency of an IF detector 18 becomes constant, and its output is inputted to a detector 15. Subsequently, a base band signal from the detector 15 is inputted to a loudspeaker 25 through a branching filter 16 and an amplifier 17.
JP18691480A 1980-12-26 1980-12-26 Radio communication system Pending JPS57111150A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP18691480A JPS57111150A (en) 1980-12-26 1980-12-26 Radio communication system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP18691480A JPS57111150A (en) 1980-12-26 1980-12-26 Radio communication system

Publications (1)

Publication Number Publication Date
JPS57111150A true JPS57111150A (en) 1982-07-10

Family

ID=16196893

Family Applications (1)

Application Number Title Priority Date Filing Date
JP18691480A Pending JPS57111150A (en) 1980-12-26 1980-12-26 Radio communication system

Country Status (1)

Country Link
JP (1) JPS57111150A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0423356U (en) * 1990-06-20 1992-02-26
CN113794495A (en) * 2021-08-18 2021-12-14 上海卫星工程研究所 High-integration high-reliability high-stability frequency source design method and system for deep space exploration

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0423356U (en) * 1990-06-20 1992-02-26
CN113794495A (en) * 2021-08-18 2021-12-14 上海卫星工程研究所 High-integration high-reliability high-stability frequency source design method and system for deep space exploration

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