| 5231667 |
Scrambling/descrambling circuit |
| Jul-27-1993 |
A scrambling/descrambling circuit that may be manufactured as a CMOS arrangement in LSI format and free of constraints on the degree of the generating polynomial involved. Scrambled (or descrambled) "m"... |
| 5222141 |
Apparatus and method for encoding data |
| Jun-22-1993 |
A first bit of the communication signal is encrypted and forwarded to a CRC where it is processed in parallel with the encryption of the second bit. The first bit is then passed to the scrambler and the... |
| 5214703 |
Device for the conversion of a digital block and use of same |
| May-25-1993 |
The device (12) comprises nine encryption stages (61.1, 61.2, 69), the first eight of which are constructed identically. It further comprises a key subblock generation unit (63), an input unit (21), and... |
| 5208858 |
Method for allocating useful data to a specific originator |
| May-4-1993 |
The hash result of useful data is transmitted to a multiply-protected central server in which it is transformed into a signature on the basis of a crypto operations system combination with a private key... |
| 5179592 |
Data scrambler and descrambler capable of preventing continuous bit zeros or ones |
| Jan-12-1993 |
A data scrambler, which transmits a data sequence, includes circuitry to suppress consecutive occurrences of a predetermined number of data sequence bits having the same value. The number of consecutive... |
| 5159634 |
Cryptosystem for cellular telephony |
| Oct-27-1992 |
A relatively secure, self-inverting, symmetric key cryptosystem designed for efficient implementation on an 8-bit microcomputer. The cryptosystem is especially well suited use in cellular telephony. The... |
| 5101430 |
Method and device for generating and for validating a digital message and application of such a device |
| Mar-31-1992 |
In this method, a number N is assigned to transmitted and receiving stations comprising synchronous clocks (2), the coded message being obtained by calculating a time Tie from the time elapsed since the... |
| 5091940 |
Data router with burst shuffling and deshuffling output buffers |
| Feb-25-1992 |
An improved data router 10 with burst deshuffling and shuffling output buffers that performs input data deshuffling and output data formatting and shuffling using only one burst buffer per input channel... |
| 5029210 |
Cooperative communication system |
| Jul-2-1991 |
A cooperating communications system in which at least two stations and a connecting communications link form a cooperative communicating loop. Each station contains a plurality of amplification stages,... |
| 5014313 |
Text modifier |
| May-7-1991 |
A method is disclosed and apparatus is described whereby plain text is modified before it is input to a binary key generator (encryptor). According to the invention, a plain text bit may be modified by... |
| 5001753 |
Crytographic system and process and its application |
| Mar-19-1991 |
The subject of the present invention is a cryptographic system, having two inverse permutations, which can be implemented in a (micro) computer whose data processing resources are relatively limited. The... |
| 4979832 |
Dynamic substitution combiner and extractor |
| Dec-25-1990 |
A first data source and a second data source are combined into a complex intermediate form or result; the first data source can be extracted from the intermediate form using the second data source. The... |
| 4972481 |
Ciphering and deciphering device |
| Nov-20-1990 |
A ciphering system comprises a ciphering device having an input for a sequence of bits to be ciphered, and output for the ciphered bit sequence, and a mixing unit connected between the input and the output.... |
| 4944006 |
Secure data packet transmission system and method |
| Jul-24-1990 |
A bit packet communication system includes a head-end having a software implemented 16 bit shift register with a plurality of feed-forward taps and a different plurality of feedback taps for simultaneously... |
| 4876718 |
Secure data packet transmission system and method |
| Oct-24-1989 |
A bit packet communication system includes a head-end having a software implemented 16 bit shaft register with a plurality of feed-forward taps and a different plurality of feed-back taps for simultaneously... |
| 4870612 |
Operator console with paired modules including means for ciphering and deciphering messages therebetween based on a mutually known, exclusive internal security code |
| Sep-26-1989 |
An operator console for data communication is divided into two separate units which can be connected electrically together, namely a keyboard (10) having a logical unit (21), with a memory (211) and a... |
| 4837737 |
System for detecting origin of proprietary documents generated by an apparatus for processing information such as words, figures and pictures |
| Jun-6-1989 |
A word processor includes a work station having a keyboard and a display device, a main unit for forming a text file in accordance with input commands entered by the keyboard, an external memory unit for... |
| 4827513 |
Communications system |
| May-2-1989 |
A communications scrambler operates on a digital basis in which digital or digitized incoming and outgoing signals are merged (60) into a single bit stream for application to a binary bit store (12) and... |
| 4815130 |
Stream cipher system with feedback |
| Mar-21-1989 |
A cipher system in which a key is initially inserted into a shift register and the serial output of the shift register is added to the plain text message and the sum is fed back into the serial input of... |
| 4771458 |
Secure data packet transmission system and method |
| Sep-13-1988 |
A bit packet communication system includes a head end having a software implemented 16 bit shift register with a plurality of feed-forward taps and a different plurality of feedback taps for simultaneously... |
| 4751733 |
Substitution permutation enciphering device |
| Jun-14-1988 |
A substitution-permutation enciphering device. This device, adapted for transforming a binary word into another binary word, by a succession of substitutions and permutations, under the control of a key,... |
| 4710957 |
Data detection by statistical analysis |
| Dec-1-1987 |
A data detector is disclosed wherein a received signal is analyzed to determine its statistical characteristics. These characteristics are compared to a predetermined statistical distribution. If the signal... |
| 4710945 |
Signal selection by statistical comparison |
| Dec-1-1987 |
A signal selection system is disclosed wherein a plurality of received signals are analyzed to determine their statistical characteristics. These characteristics are compared to a predetermined statistical... |
| 4707839 |
Spread spectrum correlator for recovering CCSK data from a PN spread MSK waveform |
| Nov-17-1987 |
In a spread spectrum communications system employing cyclic code shift keying as its primary modulation, the transmission waveform is spread for transmission security by modulo-2 adding a pseudo-noise... |
| 4694467 |
Modem for use in multipath communication systems |
| Sep-15-1987 |
A modem in which the transmitter uses spectrum spreading techniques applied to sequentially supplied input bits, a first group thereof having one spread spectrum sequence characteristic and a second group... |
| 4486853 |
Apparatus for receiving and displaying continuously updated data |
| Dec-4-1984 |
Receiving and displaying apparatus is disclosed for receiving a continuously transmitted stream of encoded data messages, whereby selected of the data messages are stored in an updateable, addressable... |
| 4313031 |
Encipher-decipher device having semi-automatic generation of the code key during data entry |
| Jan-26-1982 |
An encipher-decipher apparatus including an input keyboard and a processing and control stage which enciphers or deciphers data received directly from the keyboard or preferably from a text store with... |
| 4304962 |
Data scrambler |
| Dec-8-1981 |
Binary digital data signal patterns containing either no transitions, periodically recurring transitions or both are randomized by constructing a key signal from a summation of selected stored digits of... |
| 4301327 |
Reduction of message redundancy by multiple substitution: a message preprocessing scheme for secure communications |
| Nov-17-1981 |
The strength of a cryptosystem is increased by providing multiple characters for one or more of the characters being encoded to thereby reduce redundancy. |
| 4157454 |
Method and system for machine enciphering and deciphering |
| Jun-5-1979 |
Variable length data words are processed segment-by-segment together with corresponding segments of an enciphering key. As a function of the contents of a data segment, one of several modification modes... |
| 4087626 |
Scrambler and unscrambler for serial data |
| May-2-1978 |
Serial data is scrambled at a transmitting terminal by storing it in sequential locations in a first random access memory, while previously stored information is read out of a second random access memory... |
| 3988538 |
Digital data scrambler and descrambler |
| Oct-26-1976 |
A digital data scrambler and descrambler for m parallel synchronized digital data streams, where m is an integer greater than one, is disclosed. The scrambler and descrambler each include m linear sequential... |
