DE3688530T2 - Geraet zur vermeidung des abhoerens eines funksignals, welches zwischen einer festen einrichtung und einer mobilstation uebertragen wird. - Google Patents

Geraet zur vermeidung des abhoerens eines funksignals, welches zwischen einer festen einrichtung und einer mobilstation uebertragen wird.

Info

Publication number
DE3688530T2
DE3688530T2 DE8686101827T DE3688530T DE3688530T2 DE 3688530 T2 DE3688530 T2 DE 3688530T2 DE 8686101827 T DE8686101827 T DE 8686101827T DE 3688530 T DE3688530 T DE 3688530T DE 3688530 T2 DE3688530 T2 DE 3688530T2
Authority
DE
Germany
Prior art keywords
transmitted
mobile station
radio signal
fixed device
hearing
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.)
Expired - Fee Related
Application number
DE8686101827T
Other languages
English (en)
Other versions
DE3688530D1 (de
Inventor
Mitsunori Morishima
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.)
NEC Corp
Original Assignee
NEC Corp
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
Priority claimed from JP60027093A external-priority patent/JPS61187430A/ja
Priority claimed from JP60050061A external-priority patent/JPS61208933A/ja
Application filed by NEC Corp filed Critical NEC Corp
Publication of DE3688530D1 publication Critical patent/DE3688530D1/de
Application granted granted Critical
Publication of DE3688530T2 publication Critical patent/DE3688530T2/de
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04K—SECRET COMMUNICATION; JAMMING OF COMMUNICATION
    • H04K3/00—Jamming of communication; Counter-measures
    • H04K3/80—Jamming or countermeasure characterized by its function
    • H04K3/82—Jamming or countermeasure characterized by its function related to preventing surveillance, interception or detection
    • H04K3/825—Jamming or countermeasure characterized by its function related to preventing surveillance, interception or detection by jamming
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/24—Radio transmission systems, i.e. using radiation field for communication between two or more posts
    • H04B7/26—Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile
    • H04B7/2621—Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile using frequency division multiple access [FDMA]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04K—SECRET COMMUNICATION; JAMMING OF COMMUNICATION
    • H04K3/00—Jamming of communication; Counter-measures
    • H04K3/40—Jamming having variable characteristics
    • H04K3/45—Jamming having variable characteristics characterized by including monitoring of the target or target signal, e.g. in reactive jammers or follower jammers for example by means of an alternation of jamming phases and monitoring phases, called "look-through mode"
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04K—SECRET COMMUNICATION; JAMMING OF COMMUNICATION
    • H04K3/00—Jamming of communication; Counter-measures
    • H04K3/80—Jamming or countermeasure characterized by its function
    • H04K3/82—Jamming or countermeasure characterized by its function related to preventing surveillance, interception or detection
    • H04K3/827—Jamming or countermeasure characterized by its function related to preventing surveillance, interception or detection using characteristics of target signal or of transmission, e.g. using direct sequence spread spectrum or fast frequency hopping
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04K—SECRET COMMUNICATION; JAMMING OF COMMUNICATION
    • H04K2203/00—Jamming of communication; Countermeasures
    • H04K2203/10—Jamming or countermeasure used for a particular application
    • H04K2203/16—Jamming or countermeasure used for a particular application for telephony
DE8686101827T 1985-02-14 1986-02-13 Geraet zur vermeidung des abhoerens eines funksignals, welches zwischen einer festen einrichtung und einer mobilstation uebertragen wird. Expired - Fee Related DE3688530T2 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP60027093A JPS61187430A (ja) 1985-02-14 1985-02-14 盗聴防護方式
JP60050061A JPS61208933A (ja) 1985-03-13 1985-03-13 盗聴防護装置

Publications (2)

Publication Number Publication Date
DE3688530D1 DE3688530D1 (de) 1993-07-15
DE3688530T2 true DE3688530T2 (de) 1993-09-23

Family

ID=26364981

Family Applications (2)

Application Number Title Priority Date Filing Date
DE8686101827T Expired - Fee Related DE3688530T2 (de) 1985-02-14 1986-02-13 Geraet zur vermeidung des abhoerens eines funksignals, welches zwischen einer festen einrichtung und einer mobilstation uebertragen wird.
DE3650533T Expired - Fee Related DE3650533T2 (de) 1985-02-14 1986-02-13 Funkübertragungssystem mit Einrichtung zur Verhinderung des Abhörens eines zwischen einer Feststation und einer mobilen Station übertragenen Funkübertragungssignals

Family Applications After (1)

Application Number Title Priority Date Filing Date
DE3650533T Expired - Fee Related DE3650533T2 (de) 1985-02-14 1986-02-13 Funkübertragungssystem mit Einrichtung zur Verhinderung des Abhörens eines zwischen einer Feststation und einer mobilen Station übertragenen Funkübertragungssignals

Country Status (5)

Country Link
US (1) US4727568A (de)
EP (2) EP0191488B1 (de)
AU (1) AU582329B2 (de)
CA (1) CA1249031A (de)
DE (2) DE3688530T2 (de)

Families Citing this family (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5005200A (en) * 1988-02-12 1991-04-02 Fischer Addison M Public key/signature cryptosystem with enhanced digital signature certification
US4916728A (en) * 1988-07-25 1990-04-10 Gte Mobilnet Incorporated Cellular telephone unit with prioritized frequency acquisition
US5003598A (en) * 1989-01-23 1991-03-26 Kunstadt George H Secure communication system
JPH02241235A (ja) * 1989-03-15 1990-09-25 Toshiba Corp 無線電話装置
US4972469A (en) * 1989-05-19 1990-11-20 Syntellect Inc. System and method for communications security protection
US5181243A (en) * 1989-05-19 1993-01-19 Syntellect, Inc. System and method for communications security protection
US5148478A (en) * 1989-05-19 1992-09-15 Syntellect Inc. System and method for communications security protection
JP3015443B2 (ja) * 1990-10-11 2000-03-06 株式会社東芝 無線電話装置
US5307370A (en) * 1991-06-03 1994-04-26 Motorola, Inc. Secure cordless radio-telephone
US5778026A (en) * 1995-04-21 1998-07-07 Ericsson Inc. Reducing electrical power consumption in a radio transceiver by de-energizing selected components when speech is not present
GB2314235B (en) * 1996-06-10 2000-12-13 Motorola As A method of transmitting signals in a communications system
DE19848915C2 (de) * 1998-10-23 2000-11-02 Alcatel Sa Verbessern der Abhörsicherheit von Mobiltelefonen
KR100365514B1 (ko) * 2000-04-28 2002-12-18 주식회사 모든텔레콤 직교 호출 잡음 시뮬레이터
CN100486145C (zh) * 2003-08-15 2009-05-06 华为技术有限公司 实现空中监听的方法和监听设备

Family Cites Families (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3183313A (en) * 1960-12-16 1965-05-11 Bell Telephone Labor Inc Echo suppressor operable by a pilot tone
FR95619E (fr) * 1966-05-05 1971-03-26 It Telecommunicazioni Siemens Systeme de transmission de signaux téléphoniques a allocation de temps.
GB1189861A (en) * 1966-09-15 1970-04-29 Horace Graham Bent Security Communications Systems
CH559483A5 (de) 1973-06-12 1975-02-28 Patelhold Patentverwertung
US4241236A (en) * 1978-11-02 1980-12-23 Bell Telephone Laboratories, Incorporated Noise range indicating system
US4345261A (en) 1979-02-21 1982-08-17 Discovision Associates Dielectric recording medium
EP0015041B1 (de) * 1979-02-23 1984-04-18 Xaveer Chantrain Telekommunikationssystem des Mobilfunk-Typs
US4450319A (en) * 1981-07-31 1984-05-22 Controlonics Corporation Infrared telephone extension control system
JPS58198934A (ja) * 1982-05-17 1983-11-19 Sony Corp 秘話装置
US4543665A (en) * 1982-07-13 1985-09-24 Plantronics, Inc. Speakerphone with wireless infrared microphone
US4517561A (en) * 1982-07-28 1985-05-14 Motorola, Inc. Selective call, paging and priority signalling system
US4555592A (en) * 1983-05-23 1985-11-26 Teleconferencing Systems International, Inc. Wireless hands-free conference telephone system
EP0131919A3 (de) * 1983-07-18 1985-03-06 Motorola, Inc. Sprachgeheimhaltungssystem

Also Published As

Publication number Publication date
AU5348786A (en) 1986-08-21
EP0191488B1 (de) 1993-06-09
US4727568A (en) 1988-02-23
EP0481961B1 (de) 1996-06-19
EP0481961A2 (de) 1992-04-22
DE3688530D1 (de) 1993-07-15
EP0191488A3 (en) 1988-11-02
DE3650533D1 (de) 1996-07-25
EP0191488A2 (de) 1986-08-20
EP0481961A3 (en) 1992-07-22
DE3650533T2 (de) 1996-10-31
AU582329B2 (en) 1989-03-16
CA1249031A (en) 1989-01-17

Similar Documents

Publication Publication Date Title
GB2167273B (en) Radio frequency transmitter and method
DE3688530T2 (de) Geraet zur vermeidung des abhoerens eines funksignals, welches zwischen einer festen einrichtung und einer mobilstation uebertragen wird.
AU5802080A (en) Wireless transmitting device
JPS57192184A (en) Method and device for transmitting voice frequency information
GB8615897D0 (en) Transmitting apparatus
GB8707741D0 (en) Transmitting voice signal
EP0166543A3 (en) Mobile sound field correcting device
ZA869734B (en) Single side band harmonic frequency converter,in particular for highfrequency receiving and transmitting systems
AU5695586A (en) Sawing method, and a device for utilization of the method
JPS5797283A (en) Signal transmitting method and device used therefor
GB2216150B (en) Force transmitting band and a method for its manufacture
GB2105502B (en) Apparatus for the transmission of signals between a fixed and a mobile station
DK608087A (da) Amplitudemoduleret radiosender
GB8710716D0 (en) Transmitting data between central radio station
DE3780613T2 (de) Einrichtung zur kompensation des dopplereffektes zwischen einem empfaenger und einem sender auf derselben frequenz in einem funkempfaenger.
DE68914103D1 (de) Vorrichtung und System für Gleichfrequenzfunk mit verringerten Interferenzen.
FR2566206B1 (fr) Dispositif pour limiter la puissance d'emission d'emetteurs d'ondes radioelectriques
EP0329201A3 (en) Mobile sound field correcting device
GB8627985D0 (en) Radio transmitting & receiving apparatus
GB2083979B (en) Radio transmitting and receiving apparatus
DE3572574D1 (en) Radio transmitter identification method, and radio receiver therefor
GB2188214B (en) Method and device for combining rf transmitters
YU201586A (en) Assembly for transmitting directed radio relay signals in two or more radio relay frequency bands
GB8526208D0 (en) Adaptable transmitter & antenna arrangement
GB9121901D0 (en) High-frequency amplifier of a radio transmitter

Legal Events

Date Code Title Description
8364 No opposition during term of opposition
8339 Ceased/non-payment of the annual fee