| 6014442 |
Decrypting method and electronic device |
| Jan-11-2000 |
PID information and TSC information are extracted from a header of received data inputted to a terminal 1 and are supplied to an IDT (16). The IDT (16) receives these information and searches a data key... |
| 6009174 |
Secret key transfer method which is highly secure and can restrict the damage caused when the secret key is leaked or decoded |
| Dec-28-1999 |
A transmission apparatus 100 includes a secret key storage unit 103 that stores three secret keys K1, K2 and K3, a secret key selection unit 104 that selects one secret key Ks from the secret keys, a message... |
| 5963644 |
Process and device for making secure a telephone link connecting two subscriber sets |
| Oct-5-1999 |
A telephone link comprises two network terminals to which two subscriber sets are respectively connected, two subscriber lines respectively linking the two network terminals to two line terminals respectively... |
| 5960086 |
Unified end-to-end security methods and systems for operating on insecure networks |
| Sep-28-1999 |
Secure transmission of a message is achieved by using a one-time encryption key derived at the receiver and the sender from information present at both the sender and the receiver, but wherein the information... |
| 5956402 |
Passwordless secure and efficient remote data update |
| Sep-21-1999 |
Secure communication is effected when computers A and B that are interconnected by an insecure medium employ a dataset that is known to both and that is otherwise used within one or other of the computers... |
| 5898782 |
Method and system to secure the transmission of data elements between a sensor and a recorder |
| Apr-27-1999 |
Disclosed are a method and a system for the securing of the transmission of data elements between a sensor delivering pulses and a recorder processing these pulses. This method and system are applicable... |
| 5822430 |
System for encoding encryption/decryption information into IFF challenges |
| Oct-13-1998 |
An IFF system produces a challenge in which some or all of the anti-interference pulses that are inserted between adjacent bits of an encrypted message are replaced with "information pulses" that convey... |
| 5805705 |
Synchronization of encryption/decryption keys in a data communication network |
| Sep-8-1998 |
To enhance the security provided by data encryption in a data communication network, the encryption/decryption keys are changed periodically at the source and destination nodes for an established connection.... |
| 5706348 |
Use of marker packets for synchronization of encryption/decryption keys in a data communication network |
| Jan-6-1998 |
To enhance the security provided by data encryption in a data communication network, encryption/decryption keys are changed periodically at the source and destination nodes for an established connection.... |
| 5574785 |
Enciphered communication system |
| Nov-12-1996 |
An enciphered communication system is provided which has a plurality of cipher keys selectively used for enciphering data, wherein even when a cipher key number used at a transmitting side is not correctly... |
| 5555305 |
Method and apparatus for secure transmission of video signals |
| Sep-10-1996 |
Video signals are sampled at 4Fsc locked onto sub-carrier phase and frequency. The active picture lines of each field are divided into 6 blocks of 47 lines and the active line periods of those lines scrambled... |
| 5546464 |
Method of and apparatus for selective resynchronization in a digital cellular communications system |
| Aug-13-1996 |
In a ciphered digital cellular communications system a method and apparatus are presented for selective resynchronization of the cipher upon initial channel acquisition or handoff. Where synchronization... |
| 5541997 |
Method and apparatus for detecting correctly decrypted communications |
| Jul-30-1996 |
In a receiver (100), an encrypted communication (104) is decrypted using a decryptor (101) and a key (107) to produce a decrypted communication (105). A comparator (103) compares decrypted symbol patterns... |
| 5528693 |
Method and apparatus for voice encryption in a communications system |
| Jun-18-1996 |
A world-wide cellular radio telecommunications system utilizing low-earth orbit satellites provides secure transmissions of voice and data even though the length of the signal path of the communications... |
| 5515438 |
Quantum key distribution using non-orthogonal macroscopic signals |
| May-7-1996 |
Quantum key distribution (QKD) uses non-orthogonal quantum states to distribute random information, suitable for use as a key for encryption and authentication, between two users who share secret information... |
| 5502767 |
Method for maintaining secure information synchronization on a control channel |
| Mar-26-1996 |
Synchronization of secure information on a control channel (104) of a secure radio trunking communication system (100), is maintained by periodically transmitting control encryption parameters (CEP) (111)... |
| 5500899 |
Secure voice conferencing apparatus |
| Mar-19-1996 |
A system for communicating simultaneous encrypted messages in a jamming eronment with a low opportunity for depth exploitation. The system includes a plurality of transmitters, each having a high speed... |
| 5479513 |
Fast and secure encryption-decryption method based on chaotic dynamics |
| Dec-26-1995 |
A method and system for the secure encryption of information. The method comprises the steps of dividing a message of length L into its character components; generating m chaotic iterates from m independent... |
| 5278907 |
Analog scrambling with continuous synchronization |
| Jan-11-1994 |
A device and method for scrambling and de-scrambling audio and voice communications including radio, cellular telephone, and conventional telephone communication. The audio communication can be scrambled... |
| 5243653 |
Method and apparatus for maintaining continuous synchronous encryption and decryption in a wireless communication system throughout a hand-off |
| Sep-7-1993 |
In a wireless communication system comprising a plurality of fixed communication units (FCUs) (102) and portable communication units (PCUs) (120), each comprising an encryption synchronization counter... |
| 5239581 |
Secret communication apparatus |
| Aug-24-1993 |
This secret communication apparatus used in an audio and data transmission system has scramble/descramble circuits formed of programmable logic means. A control circuit in the apparatus instructs the programmable... |
| 5182772 |
Method and apparatus for encoding, transmitting, receiving and de-coding information |
| Jan-26-1993 |
A clear language dictionary of items of information to be transmitted is provided for composing messages and is also electronically impressed in first memory elements of sending and receiving computers.... |
| 5081679 |
Resynchronization of encryption systems upon handoff |
| Jan-14-1992 |
A system for the synchronization of encryption and decryption in a duplex cellular radio system in which an encrypted call may be switched from one cell to another. At the instant of handoff, a rapid first... |
| 5022079 |
Lock means and TV sync for air-to-surface missile |
| Jun-4-1991 |
1. A digital code synchronization locking means comprising: means to receive a first digital code sequence; means to generate a second digital code sequence substantially similar to id first sequence,... |
| 5016275 |
Buffered encryption/decryption |
| May-14-1991 |
Encryption and decryption mechanisms at transmitters and receivers, respectively, have applied thereto encryption or decryption keys and initializing values. These mechanisms generate cryptographic bit... |
| 5003598 |
Secure communication system |
| Mar-26-1991 |
A secure communication system comprising signal manipulation and inverse signal manipulation means at the sending and receiving locations respectively, the signal manipulation processes being controlled... |
| 5003593 |
Teleconferencing method for a secure key management system |
| Mar-26-1991 |
A secure teleconferencing method for a key management system is shown. This method directly establishes a secure teleconference among a number of terminals without the intervention of a certifying authority.... |
| 4991209 |
Random local message encryption |
| Feb-5-1991 |
Data transmission to an aircraft is secured by encrypting the data between a remote data source and the aircraft. The encryption is initiated when a random number is coupled to the remote location where... |
| 4977596 |
Cryptographic synchronization recovery by measuring randomness of decrypted data |
| Dec-11-1990 |
The invention relates to synchronization of encrypted data communication systems and a method which looks for any lack of pattern or intelligent information in the received data and triggers a resynchronization... |
| 4969191 |
Fully digital phase-locked loop |
| Nov-6-1990 |
A fully digital phase-locked loop comprises a sampler (1), an analog-to-digital converter (2), two quadrature demodulators (3 and 4) and their associated filters (5 and 6), and a decision logic (7) effecting... |
| 4935961 |
Method and apparatus for the generation and synchronization of cryptographic keys |
| Jun-19-1990 |
A method and apparatus for generating cryptographic keys for a postal manifest and for synchronizing cryptographic keys for transmitting postal data securely on a communication link is presented. The techniques... |
| 4817145 |
Generator for generating binary ciphering sequences |
| Mar-28-1989 |
A generator for generating ciphering sequences, including plural clocked subgenerators (.GAMMA., .psi., .PSI.) which, in turn, generate binary sequences at one or several outputs. To achieve high cryptographic... |
| 4805216 |
Method and apparatus for continuously acknowledged link encrypting |
| Feb-14-1989 |
The method and apparatus of the invention described herein provide confidential communications between two or more stations whereby the exchanged messages themselves provide the necessary enciphering keys... |
| 4803726 |
Bit synchronization method for a digital radio telephone system |
| Feb-7-1989 |
A method and means for maintaining continuous bit synchronization of data transmitted from a remote unit through a base unit to a landline unit is disclosed. An input data stream at a first bit rate, such... |
| 4794644 |
Method of secured communications in a telecommunications system |
| Dec-27-1988 |
The Telecommunications system includes at least two exchanges and a plurality of user equipments. Each equipment includes a store for holding a user variable data word particular to that user. Each exchange... |
| 4790012 |
Encryption-decryption system |
| Dec-6-1988 |
In a data encrypting/decrypting system both the encoding and decoding stations are receptive of a common source of time varying digital signals. The digital signals in the encoding station are applied... |
| 4688257 |
Secure wireless communication system utilizing locally synchronized noise signals |
| Aug-18-1987 |
Apparatus and method are disclosed for synchronziing the operation of the frequency sensitive devices of two or more transceiver units in a secure, wireless communication system. A fixed frequency pilot... |
| 4636583 |
Synchronization of long codes of bounded time uncertainty |
| Jan-13-1987 |
Apparatus and method for synchronizing two code streams in a digital commcation network. A locally generated code stream is stored in a precessing delay line and correlated with a received code stream... |
| 4465153 |
Method of coding and decoding messages |
| Aug-14-1984 |
Method of coding and decoding messages wherein a basic key and a random message key, which is transmitted prior to the message, are used. Using a plurality of basic keys entails the problem that the proper... |
| 4434323 |
Scrambler key code synchronizer |
| Feb-28-1984 |
A method for synchronizing the scrambling sequences of communicating scrambler units of a privacy communications system in a reliable and secure manner. The method is particularly adapted for use in noisy... |
| 4429180 |
Apparatus for simultaneous generation of key at two locations |
| Jan-31-1984 |
An apparatus for simultaneously generating identical cipher key at two remote terminals in a manner which prohibits interception of the key by unauthorized persons. A circuit comprising three separate... |
| 4401854 |
Simultaneous transmission of an analog message signal and a digital data signal |
| Aug-30-1983 |
In its most general form, the present invention may be employed to simultaneously transmit information, either digital or analog, from two separate and distinct sources, denoted A and B, where the information... |
| 4386234 |
Cryptographic communication and file security using terminals |
| May-31-1983 |
A data security device which includes storage means for storing a master cipher key, cryptographic apparatus for performing cryptographic operations and control means for controlling the writing of a master... |
| 4353126 |
Method for coded data transmission in half-duplex operation between data terminal equipment of two data stations |
| Oct-5-1982 |
A method for the coded data transmission in half-duplex operation between data terminal devices of two data stations employs a code device of the one data station to transmit a phase-in program to the... |
| 4208544 |
Checker and automatic synchronizer for coding equipment |
| Jun-17-1980 |
1. A one way communication system comprising means for transmitting coded pulse data and synchronizing pulses from a transmitter to a receiver having a source of clock pulses, monitoring means connected... |
| 4187392 |
Synchronous universal binary scrambler |
| Feb-5-1980 |
1. A synchronous binary cryptographic system responsive to an input synchronous telegraph signal comprising means for generating timing pulses of substantially fixed, predetermined frequency, means for... |
| 4172963 |
Checker and automatic synchronizer for coding equipment |
| Oct-30-1979 |
1. A system comprising a pair of stations having two parallel communication links therebetween, means for transmitting coded data signals of varying levels between the stations in opposite directions over... |
| 4171513 |
Secure communications system |
| Oct-16-1979 |
A privacy communication system is herein disclosed comprising apparatus for digitizing information to be transmitted, apparatus for logically adding a selected pseudo-random digital code to the digitized... |
| 4166922 |
Multi-mode digital enciphering system with repeated priming sequences |
| Sep-4-1979 |
The specification discloses an electronic digital enciphering system which is selectively operable in a plurality of different modes. The system may be operated in an off-line mode for preparing enciphered... |
| 4159399 |
Security communication system using polarity inversion |
| Jun-26-1979 |
In a security communication system, the transmitting unit includes a sample - hold circuit for sampling and holding the original voice signal, an inverting circuit for inverting the polarity of the samples... |
