Patents
Sitemap › H04 - Electric communication technique › H04K - Secret communication; Jamming of communication › H04K 1 - Secret communication
Patents for H04K 1 - Secret communication (16,771)
06/1983
06/28/1983US4390899 Television signal processing system
06/14/1983CA1148252A1 Solid state digital audio scrambler system for teletransmission of audio intelligence through a television system
06/07/1983US4387393 Signal unscrambler
05/1983
05/26/1983WO1983001881A1 A security system for sstv encryption
05/11/1983WO1983001717A1 Privacy communication system employing time/frequency transformation
04/1983
04/19/1983CA1145010A1 Receiver and correlator switching method
04/06/1983EP0075888A2 Method for transmitting bandlimited speech signals with protection against eavesdropping
04/05/1983US4379205 Analog signal scrambling system
03/1983
03/23/1983EP0074657A1 Method of securing the transmission of digital signals
03/09/1983EP0073323A1 Encrypted data transmission in a TDMA satellite communications network
03/08/1983CA1142637A1 Analog signal encrypting and decrypting system
01/1983
01/25/1983US4370519 Autokey generator for secret communication system
01/18/1983US4369462 Coding system for pay television
01/12/1983EP0069477A1 Radio communications apparatus
01/05/1983EP0068690A1 Radio communications receivers
12/1982
12/21/1982US4365111 Cipher apparatus for multiplex pulse code modulation systems
12/01/1982EP0065648A1 Method for frequency scrambling sub-bands
12/01/1982EP0065636A1 Method of scrambling n sub-bands
11/1982
11/30/1982US4361729 Narrowband analog message privacy system
11/24/1982EP0065210A2 Electrical signal conditioning method with a digital filter device
11/16/1982CA1135795A1 Encoding of information
11/09/1982US4358857 Communication system
09/1982
09/22/1982EP0060299A1 Multiple signal transmission method and system, particularly for television.
09/21/1982US4351064 Communication
08/1982
08/25/1982EP0058318A1 Sub-band permutation method
08/10/1982US4343970 Signaling system
07/1982
07/06/1982CA1127258A1 Method and apparatus for enciphering blocks which succeed short blocks in a key-controlled block-cipher cryptographic system
05/1982
05/11/1982US4329711 Apparatus for encoding of information
04/1982
04/28/1982EP0050268A1 Apparatus for encrypted transmission of information
04/20/1982US4326292 Random energy communication system
04/20/1982US4326098 High security system for electronic signature verification
04/06/1982US4324002 Delay-modulated random energy intelligence communication system
04/06/1982CA1121480A1 Cryptographic apparatus and method
04/01/1982WO1982001109A1 Multiple signal transmission method and system,particularly for television
03/1982
03/30/1982US4322576 Message format for secure communication over data links
03/09/1982US4319087 Secret communication system
03/09/1982CA1119670A1 Continuously synchronized tracking receiver for a priori defined swept carrier
03/02/1982US4318125 Solid state digital audio scrambler system for teletransmission of audio intelligence through a television system
03/02/1982CA1119268A1 Cryptographic verification of operational keys used in communication networks
02/1982
02/09/1982US4315101 Method and apparatus for securing data transmissions
01/1982
01/26/1982US4313133 Scrambling and descrambling system in CATV broadcasting system
01/19/1982US4312072 Radio frequency transmission system
01/12/1982US4310720 Computer accessing system
01/06/1982EP0043027A1 Electronic signature verification method and system
12/1981
12/30/1981EP0042587A1 Method of transforming speech signals subdivided into signal segments for enciphered transmission, and apparatus for realizing this method
12/29/1981US4308617 Noiselike amplitude and phase modulation coding for spread spectrum transmissions
12/29/1981US4308556 Television video signal scrambling system
12/08/1981US4305152 Security communication system
12/01/1981CA1113567A1 Secure communication system
11/1981
11/24/1981US4302628 Analog signal encrypting and decrypting system
11/04/1981EP0038875A1 Process and circuit for data eneryption
10/1981
10/14/1981EP0037762A1 Method and system for transmitting signed messages
08/1981
08/11/1981US4283602 Cryptographically secure communication system
08/06/1981WO1981002234A1 Process and device for protecting the transmission of vocal signals
07/1981
07/21/1981US4280222 Receiver and correlator switching method
07/14/1981US4278840 Dynamic frequency and time voice encryption system and method
07/14/1981CA1105089A1 Method of and apparatus for transmitting clandestine radio signals
07/09/1981WO1981001933A1 Message format for secure communication over data links
06/1981
06/30/1981US4276652 Secure communication system with improved frequency-hopping arrangement
06/02/1981US4271331 Analog processing system for real-time conversion of the frequency of analog signals
06/02/1981CA1102453A1 Computer accessing system
05/1981
05/20/1981EP0028688A1 Lay-out for transmitting control signals via a speech channel
05/19/1981US4268720 Scrambler speech transmission and synchronization system
05/12/1981CA1101116A1 Subscription tv audio carrier recovery system
05/06/1981EP0028007A1 Radio system with synchronisation of the subscribers' equipments
05/05/1981US4266095 Binary code randomizing system
04/1981
04/29/1981EP0027572A1 Method and apparatus for ciphered transmission of information
03/1981
03/17/1981CA1097794A1 Secure television transmission system
01/1981
01/13/1981US4245346 Communication system
01/06/1981US4244053 Privacy communication method and system
12/1980
12/23/1980CA1092195A1 Method and apparatus for enciphering and deciphering audio information
11/1980
11/12/1980EP0018869A1 Arrangement for encrypting and decrypting an analog signal by time compressions and expansions
11/12/1980EP0018784A1 Communication system with digital audio scrambler and unscrambler subsystems for transmission of audio intelligence through a television system
11/04/1980US4232194 Voice encryption system
11/04/1980US4232193 Message signal scrambling apparatus
10/1980
10/28/1980US4231113 Anti-jam communications system
10/21/1980US4229818 Method and apparatus for enciphering blocks which succeed short blocks in a key-controlled block-cipher cryptographic system
10/14/1980US4228321 Privacy transmission system with remote key control
09/1980
09/30/1980US4225935 Coding method and system with enhanced security
09/16/1980US4223182 Transmission of signals with privacy
09/09/1980US4222115 Spread spectrum apparatus for cellular mobile communication systems
09/09/1980US4221931 Time division multiplied speech scrambler
08/1980
08/12/1980US4217469 Coding and decoding apparatus for the protection of communication secrecy
07/1980
07/22/1980US4214126 Cadence suppression system
07/09/1980EP0012974A1 Method for enciphering data blocks of a given length
07/08/1980US4211468 Method and apparatus to provide a secure optical communication system
06/1980
06/24/1980US4209750 Swept-carrier transmission system adapted for use in process control systems
06/17/1980US4208734 Underwater communication system
06/03/1980US4206462 Secure communication and ranging system
06/03/1980US4206319 Tune delay scramble equipment
05/1980
05/13/1980US4203164 Secure sonar communication system
05/13/1980CA1077630A1 Speech scrambler
03/1980
03/25/1980US4195202 Voice privacy system with amplitude masking
03/11/1980US4193131 Cryptographic verification of operational keys used in communication networks
03/11/1980US4193030 Frequency hopping communication system
02/1980
02/20/1980EP0008087A1 Device for realizing a scrambled transmission of information
02/20/1980EP0008086A1 Device for realizing a scrambled transmission of information
02/12/1980US4188580 Secure communication system
02/12/1980US4188506 Method and installation for masked speech transmission over a telephone channel
02/05/1980US4187403 Voice-protected, frequency-selective signal receiver
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