Including Frame Synchronization Patents (Class 380/261)
  • Patent number: 7804960
    Abstract: A system for the encryption and decryption of data employing dual ported RAM for key storage to accelerate data processing operations. The on-chip key storage includes a dual-ported memory device which allows keys to be loaded into memory simultaneous with keys being read out of memory. Thus, an encryption or decryption algorithm can proceed while keys are being loaded into memory.
    Type: Grant
    Filed: March 24, 2009
    Date of Patent: September 28, 2010
    Assignee: Cisco Technology, Inc.
    Inventor: Kenneth W. Batcher
  • Patent number: 7792300
    Abstract: A method for re-encrypting encrypted data in a secure storage file system, including obtaining selected data to re-encrypt from the secure storage file system using a user data access record and the encrypted data, decrypting the selected data using a symmetric key, re-encrypting the selected data using a new symmetric key to obtain new encrypted data, encrypting the new symmetric key using a public key to obtain a new encrypted symmetric key, storing the new encrypted data and the new encrypted symmetric key if the public key is associated with a file system user having read permission, and storing an encrypted hash data if the file system user has write permission.
    Type: Grant
    Filed: September 30, 2003
    Date of Patent: September 7, 2010
    Assignee: Oracle America, Inc.
    Inventor: Germano Caronni
  • Patent number: 7730296
    Abstract: Aspects of the invention provide a method and system for coding information in a communication channel. More particularly, aspects of the invention provide an method and system for synchronous running encryption and/or encoding and corresponding decryption and decoding in a communication channel or link. Aspects of the method may include encoding and/or encrypting a first data using a first or second encoding table and/or a first or second encryption table. The method may indicate which one of the first or second encoding tables or which one of the first or second encryption tables were utilized for encoding and/or encrypting the said first data. The encoded and/or encrypted first data may subsequently be transferred downstream and decoded by synchronous decoder/decryptor using a corresponding decoding and/or decryption table. The corresponding decoding and/or decryption table may be determined based on the indicated first and/or second encoding and/or encrypting tables.
    Type: Grant
    Filed: June 4, 2003
    Date of Patent: June 1, 2010
    Assignee: Broadcom Corporation
    Inventor: Martin Lund
  • Patent number: 7668314
    Abstract: An encrypted data communication system for communicating an encrypted stream as an encrypted data stream from a device at transmitting end to a device at receiving end to suppress the effect of an erroneous detection of a dummy code is disclosed. A device at transmitting end generates a data stream having the bit sequence of a marker for determination, a synchronization marker and a location identification code after the data, encrypts the bit sequence of the data and the marker for determination and transmits the encrypted stream. A device at receiving end receives the encrypted stream, detects the bit sequence of the synchronization marker and the location identification code and decrypts the encrypted stream. In the case where the bit sequence of the data and the marker for determination is decrypted, the detection of the valid bit sequence is determined, while the detection of a dummy bit sequence is determined otherwise.
    Type: Grant
    Filed: February 27, 2006
    Date of Patent: February 23, 2010
    Assignee: Hitachi Kokusai Electric, Inc.
    Inventors: Munemitsu Kuwabara, Sumie Nakabayashi
  • Patent number: 7649998
    Abstract: There is disclosed a method, apparatus, computer program and computer program product for facilitating secure data communications. The secure data communications is carried out using a secret key for encrypting data flowing between first and second entities over a communications link. First it is determined that the communications link has been idle. Once it is determined that there is now data to flow over the previously idle communications link, the generation of a new secret key is initiated. This new secret key is then used for encrypting data sent between the first and the second entities over the communications link.
    Type: Grant
    Filed: March 1, 2005
    Date of Patent: January 19, 2010
    Assignee: International Business Machines Corporation
    Inventors: Richard Michael Wyn Harran, Michael Horan, Jonathan Rumsey
  • Patent number: 7623723
    Abstract: A technique is provided for filtering noise in digital image data, particularly random point or spike noise. Image data may be rank order filtered and absolute differences between ordered values computed to create a mask. Blending is performed based upon a likelihood that individual pixels are or exhibit spike noise. The rank order filtered values may be used directly for blending, or the original image may be shrunk and then expanded to provide a rapid and computationally efficient spike noise reduction alternative.
    Type: Grant
    Filed: November 26, 2003
    Date of Patent: November 24, 2009
    Assignee: GE Medical Systems Global Technology Com.
    Inventor: Gopal B. Avinash
  • Patent number: 7532727
    Abstract: A system for the encryption and decryption of data employing dual ported RAM for key storage to accelerate data processing operations. The on-chip key storage includes a dual-ported memory device which allows keys to be loaded into memory simultaneous with keys being read out of memory. Thus, an encryption or decryption algorithm can proceed while keys are being loaded into memory.
    Type: Grant
    Filed: February 27, 2006
    Date of Patent: May 12, 2009
    Inventor: Kenneth W. Batcher
  • Patent number: 7522727
    Abstract: A method includes receiving an authentication request from a mobile station (401) and determining whether to forward the request to an authentication agent. When it is determined to forward the request, the request is forwarded to the authentication agent (107). A random number and a random seed are received from the authentication agent (107). The random number and the random seed are forwarded to the mobile station (401). A response to the random number and the random seed from the mobile station (401) is received and forwarded to the authentication agent (107). The authentication agent (107) compares the response with an expected response. When the authentication agent (107) authenticates the mobile station (401), a derived cipher key is received from the authentication agent (107).
    Type: Grant
    Filed: August 31, 2006
    Date of Patent: April 21, 2009
    Assignee: Motorola, Inc.
    Inventors: Hans Christopher Sowa, Daniel J. McDonald, David J. Chater-Lea, Scott J. Pappas, Jason Johur, Dennis Newkirk, Randy Kremske, Walter F. Anderson
  • Patent number: 7505594
    Abstract: A method and apparatus for controlling a discontinuous transmission process. Audio information is digitized and provided to a vocoder. A voice activity level is determined from the digitized audio signal, and if voice activity is present, active vocoder frames are generated at a predetermined output rate. If voice activity is not detected, inactive vocoder frames are generated. During transitions between periods of speech activity and speech inactivity, transition frames are generated, the transition frames comprising background noise information.
    Type: Grant
    Filed: December 19, 2000
    Date of Patent: March 17, 2009
    Assignee: QUALCOMM Incorporated
    Inventor: Anthony Mauro
  • Patent number: 7474749
    Abstract: A method and apparatus for achieving crypto-syncronization in a packet data communication system employing cryptographic communications. In a transmitter, a state vector is incremented at a predetermined rate and is provided to an encryption module. The encryption module uses the state vector to sequentially encrypt the data frames. During periods of frame dropping prior to encryption, the state vector is disabled, thereby allowing for sequential encryption of the data frames. In a receiver, during a frame dropping condition, the state vector is advanced in proportion to the number of frames dropped. During an underflow condition at the receiver, the state vector is disabled for the duration of the underflow condition, and enabled once the underflow condition has passed.
    Type: Grant
    Filed: February 6, 2006
    Date of Patent: January 6, 2009
    Assignee: QUALCOMM Incorporated
    Inventor: Anthony P. Mauro
  • Patent number: 7434052
    Abstract: In a method for producing an encrypted method payload data stream comprising a header and a block containing encrypted payload data, a payload data key for a payload data encryption algorithm for encrypting payload data is generated. The payload data is encrypted using the generated payload data key and the payload data encryption algorithm to obtain the block containing the encrypted payload data of the payload stream. A part of the payload data stream is processed to deduce information marking the part of the payload data stream. The information is linked with the payload data by means of an invertible logic linkage to obtain a basic value. This basic value is finally encrypted using a key of two keys being different from each other by an asymmetrical encryption method, the two different keys being the public and the private keys respectively for the asymmetrical encryption method to obtain an output value being an encrypted version of the payload data key.
    Type: Grant
    Filed: December 15, 1999
    Date of Patent: October 7, 2008
    Assignee: Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e.V.
    Inventor: Niels Rump
  • Patent number: 7424116
    Abstract: A method includes receiving an authentication request from a mobile station (401) and determining whether to forward the request to an authentication agent. When it is determined to forward the request, the request is forwarded to the authentication agent (107). A random number and a random seed are received from the authentication agent (107). The random number and the random seed are forwarded to the mobile station (401). A response to the random number and the random seed from the mobile station (401) is received and forwarded to the authentication agent (107). The authentication agent (107) compares the response with an expected response. When the authentication agent (107) authenticates the mobile station (401), a derived cipher key is received from the authentication agent (107).
    Type: Grant
    Filed: August 31, 2006
    Date of Patent: September 9, 2008
    Assignee: Motorola, Inc.
    Inventors: Hans Christopher Sowa, Daniel J. McDonald, David J. Chater-Lea, Scott J. Pappas, Jason Johur, Dennis Newkirk, Randy Kremske, Walter F. Anderson
  • Patent number: 7369662
    Abstract: A method and an arrangement maintain end-to-end synchronization on a telecommunications connection transmitting data in frames substantially in real time and using synchronized end-to-end encryption, wherein at least a part of the telecommunications connection is a packet-switched connection, in which case the reproduction delay of the data to be transmitted can be increased by adding one or more extra frames to the frame string being transmitted, wherein the arrangement defines, based on the number of received frames, an initialization vector value corresponding to a frame received at the receiving end of the telecommunications connection and used in decrypting the frame, adjusts the reproduction delay to mark the frame to be added to increase the reproduction delay as an extra frame, and defines the initialization vector value to count only the frames not marked as extra frames in the number of received frames.
    Type: Grant
    Filed: November 27, 2001
    Date of Patent: May 6, 2008
    Assignee: Eads Secure Networks Oy
    Inventors: Rasmus Relander, Raimo Kantola
  • Publication number: 20080101607
    Abstract: A method of synchronizing the encryption/decryption functions of an AlphaEta physical-layer encryption or key generation system. The method includes the insertion of a header to indicate the start of encryption after clock-synchronization has been established. The method also allows for a side-channel to signal other useful information, such as a loss-of-syncrhonization signal from Bob or to synchronize a dynamic key change.
    Type: Application
    Filed: April 13, 2006
    Publication date: May 1, 2008
    Inventors: Chuang Liang, Gregory S. Kanter, Corndorf Eric, Prem Kumar
  • Patent number: 7366917
    Abstract: A method for accessing discrete data includes transmitting a write command to a memory, determining whether each data following a header of the file needs to be encrypted according to a data format of a file that is to be written into the memory, transmitting the file header and each data following the file header to a logic unit, turning on the logic unit for encrypting the data determined to be encrypted and writing the encrypted data into the memory, turning off the logic unit for writing the data determined not to be encrypted into the memory directly, and sending a first response signal from the memory when the writing of the file is finished.
    Type: Grant
    Filed: September 17, 2004
    Date of Patent: April 29, 2008
    Assignee: Faraday Technology Corp.
    Inventor: Yung-Cheng Shih
  • Patent number: 7362864
    Abstract: Framing transmit encoded output data begins by determining a scrambling remainder between scrambling of an input code word in accordance with a 1st scrambling protocol and the scrambling of the input code word in accordance with an adjustable scrambling protocol. The processing continues by adjusting the adjustable scrambling protocol based on the scrambling remainder to produce an adjusted scrambling protocol. The processing continues by scrambling the input code word in accordance with the 1st scrambling protocol to produce a 1st scrambled code word. The processing continues by scrambling the input code word in accordance with the adjusted scrambling protocol to produce a scrambled partial code word. The processing continues by determining a portion of the 1st scrambled code word based on the scrambling remainder. The process continues by combining the scrambled partial code word with the portion of the 1st scrambled code word to produce the transmit encoded output data.
    Type: Grant
    Filed: September 11, 2003
    Date of Patent: April 22, 2008
    Assignee: Xilinx, Inc.
    Inventors: Joseph Neil Kryzak, Aaron J. Hoelscher
  • Patent number: 7277546
    Abstract: Methods and apparatus for converting original data into a plurality of sub-bands using wavelet decomposition; encrypting at least one of the sub-bands using a key to produce encrypted sub-band data; and transmitting the encrypted sub-band data to a recipient separately from the other sub-bands.
    Type: Grant
    Filed: April 9, 2004
    Date of Patent: October 2, 2007
    Assignee: New Jersey Institute of Technology
    Inventor: Atam P. Dhawan
  • Patent number: 7251729
    Abstract: An authentication method for establishing a connection between devices that want to communicate data in a communication environment using communication specification such as Bluetooth is provided. In the authentication method, it is determined whether the authentication procedure for establishing a connection between devices that want to communicate data is performed as a unilateral authentication procedure or as a mutual authentication procedure, according to the condition of one of the two devices that can communicate data and receives an authentication request, and performing the authentication procedure. Therefore, the authentication method more reliably and precisely establishes a connection between devices that want to communicate data in a communication environment operating based on communication specifications such as Bluetooth.
    Type: Grant
    Filed: November 27, 2000
    Date of Patent: July 31, 2007
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Jae-han Park
  • Patent number: 7245725
    Abstract: A dual processor framer includes a receiver and a transmitter which share common circuitry and/or code. Separate direct memory access controllers may be used for each of the receiver and transmitter. Processing is distributed over two or more processors. One processor may be a lower power processor while another processor may be a higher power processor. At least one of the two or more processors may be programmable or reconfigurable. The transceiver is configured to provide internal loop back self testing at various points in the processing. Timing within the transceiver may be established almost entirely by a single clock domain.
    Type: Grant
    Filed: May 17, 2002
    Date of Patent: July 17, 2007
    Assignee: Cypress Semiconductor Corp.
    Inventor: Paul Beard
  • Patent number: 7188248
    Abstract: The invention provides a method of recovering from de-synchronization attacks includes registering original and altered digital content using nonlinear transformations to iteratively attempt to provide better-approximated registration. Approximation occurs at more than one level of granularity, by selecting among a greater number of possible transformation functions at each step. Transformations and comparisons might be conducted directly on pixel values, on coefficients for a set of basis wavelets, or on some transformation of the original and altered digital content. A human operator might assist this process, such as by suggesting transformations or providing evaluation of the degree of registration. Upon resynchronization, embedded identifying information in the original digital content is recovered.
    Type: Grant
    Filed: February 28, 2003
    Date of Patent: March 6, 2007
    Assignee: Kaleidescope, Inc.
    Inventor: Stephen Watson
  • Patent number: 7155011
    Abstract: The present invention relates to an encryption method for encrypting information including a series of multiple unit blocks, one at a time, a decryption method for decrypting multiple encrypted unit blocks, one at a time, and a recording and reproducing apparatus that uses those methods. The seed of an encryption key for encrypting each unit block and the seed of an encryption key for decrypting each encrypted unit block, which are used by those methods and the recording and reproducing apparatus, are based on a unit block that is one or more unit blocks before the current unit block in a reproduction order or on information generated by encrypting one or more unit blocks before the current unit block. Alternatively, the seed of an encryption key for encrypting each unit block and the seed of an encryption key for decrypting each encrypted unit block are information based on an encryption key for encrypting a unit block before the current unit block in a reproduction order.
    Type: Grant
    Filed: March 8, 2002
    Date of Patent: December 26, 2006
    Assignee: Victor Company of Japan, Limited
    Inventors: Kenjiro Ueda, Takayuki Sugahara, Wataru Inoha, Seiji Higurashi, Toshio Kuroiwa
  • Patent number: 7051203
    Abstract: Input signals are electronically watermarked using an uneven or non-uniform sampling rate. The uneven or non-uniform sampling may be pseudo-random. The uneven or non-uniform sampling meets the Nyquist criterion so that aliasing and loss of content are avoided. The resulting sampling pattern in the sampled data is detectable by a comparison with the original source data.
    Type: Grant
    Filed: November 8, 1999
    Date of Patent: May 23, 2006
    Assignee: International Business Machines Corporation
    Inventor: Gordon James Smith
  • Patent number: 7023992
    Abstract: In a data multiplexing device which multiplexes and transmits the transport stream packets of program data consisting of a plurality of data elements constructed in the form of transport stream packets, a program distribution system, a program transmission system, a pay broadcast system, a program transmission method, a conditional access system, and a data reception device according to the present invention, by generating a scramble key Ks corresponding to one or more data elements among the plurality of data elements constituting a program and by scrambling each data element, an audience can subscribe for each data element.
    Type: Grant
    Filed: August 9, 1999
    Date of Patent: April 4, 2006
    Assignee: Sony Corporation
    Inventors: Tatsuya Kubota, Norio Wakatsuki
  • Patent number: 7006634
    Abstract: A system for the encryption and decryption of data employing dual ported RAM for key storage to accelerate data processing operations. The on-chip key storage includes a dual-ported memory device which allows keys to be loaded into memory simultaneous with keys being read out of memory. Thus, an encryption or decryption algorithm can proceed while keys are being loaded into memory.
    Type: Grant
    Filed: September 28, 2000
    Date of Patent: February 28, 2006
    Assignee: Cisco Technology, Inc.
    Inventor: Kenneth W. Batcher
  • Patent number: 7003114
    Abstract: A method and apparatus for achieving crypto-syncronization in a packet data communication system employing cryptographic communications. In a transmitter, a state vector is incremented at a predetermined rate and is provided to an encryption module. The encryption module uses the state vector to sequentially encrypt the data frames. During periods of frame dropping prior to encryption, the state vector is disabled, thereby allowing for sequential encryption of the data frames. In a receiver, during a frame dropping condition, the state vector is advanced in proportion to the number of frames dropped. During an underflow condition at the receiver, the state vector is disabled for the duration of the underflow condition, and enabled once the underflow condition has passed.
    Type: Grant
    Filed: January 20, 2000
    Date of Patent: February 21, 2006
    Assignee: Qualcomm Incorporated
    Inventor: Anthony P. Mauro
  • Patent number: 6983022
    Abstract: A data-modulating apparatus for modulating data having a basic data length of m bits, to a variable-length code(d, k; m, n: r) having a basic code length of n bits. A sync signal is added to a recieved train of codes after a minimum run, the sync signal having a pattern that breaks a maximum run. The pattern is repeated twice continuously, and the minimum run is repeated no more than six times. The first bit of the sync signal is “1” when the train of modulated codes that immediately precedes the sync signal is included in the termination table used to terminate, at a desired position, a code when less than a predetermined number of variable length codes are available.
    Type: Grant
    Filed: March 10, 2005
    Date of Patent: January 3, 2006
    Assignee: Sony Corporation
    Inventors: Toshiyuki Nakagawa, Yoshihide Shimpuku, Tatsuya Narahara
  • Patent number: 6952480
    Abstract: An encryption system has been provided to self-synchronously scramble communications where the receiver must recover the clock information from the data stream, such as the SONET format. To prevent jamming during initialization, or during times when no data is being transferred, flags and overhead data are scrambled, along with the payload. Timing controls to the scrambler permit this scrambler to be selectively engagable, so that the selective overhead scrambling becomes a second layer of scrambling. A method of self-synchronously scrambling the overhead in NRZ formatted communications is also provided.
    Type: Grant
    Filed: September 20, 1999
    Date of Patent: October 4, 2005
    Assignee: Applied Micro Circuits Corporation
    Inventor: Gary D. Martin
  • Patent number: 6925183
    Abstract: 23A wireless communications device has a first security key, a second security key, and established channels. Each established channel has a corresponding security count value, and utilizes a security key. At least one of the established channels utilizes the first security key. The second security key is assigned to a new channel. A first set is then used to obtain a first value. The first set has only security count values of all the established channels that utilize the second key. The first value is at least as great as the x most significant bits (MSBx) of the greatest value in the first set. The MSBx of the initial security count value for the new channel is set equal to the first value. If the first set is empty, then the initial security count is set to zero.
    Type: Grant
    Filed: August 16, 2001
    Date of Patent: August 2, 2005
    Assignee: ASUSTeK Computer Inc.
    Inventors: Sam Shiaw-Shiang Jiang, Richard Lee-Chee Kuo, Chi-Fong Ho
  • Patent number: 6920557
    Abstract: A method and system for providing external user interfaces is described. In one configuration a co-located external processor and a business machine negotiate a communications connection. The co-located external processor then utilizes a server to determine a shared secret in order to pair a wireless connection with the business machine in order to act as the user interface for the business machine. In another configuration, the co-located external processor is connected to a remote data center that authenticates the user and provides the user interface code and secret pairing information to the co-located external processor. In another configuration, the co-located external processor performs data processing for providing a cryptographically processed print stream to a postage meter.
    Type: Grant
    Filed: June 28, 2002
    Date of Patent: July 19, 2005
    Assignee: Pitney Bowes Inc.
    Inventors: Jean-Hiram Coffy, Edilberto I. Salazar
  • Patent number: 6879637
    Abstract: A method and apparatus for modulating data modulates data having a length of m-bits to a variable length code having a basic code length of n-bits. A SYNC but insertion section adds a sync signal to a train of codes, after a minimum run. The sync signal has a pattern that breaks a maximum run.
    Type: Grant
    Filed: August 24, 1999
    Date of Patent: April 12, 2005
    Assignee: Sony Corporation
    Inventors: Toshiyuki Nakagawa, Yoshihide Shimpuku, Tatsuya Narahara
  • Patent number: 6873707
    Abstract: A system for the encryption and decryption of data employing cycle stealing to accelerate data processing operations. The cycle stealing is employed by using level sensitive latches in a microcode controller system for storing addresses and code words. The microcode controller system controls the data path hardware for executing the encryption/decryption operations.
    Type: Grant
    Filed: September 28, 2000
    Date of Patent: March 29, 2005
    Assignee: Cisco Technology, Inc.
    Inventor: Kenneth W. Batcher
  • Publication number: 20040223615
    Abstract: Methods and apparatus for converting original data into a plurality of sub-bands using wavelet decomposition; encrypting at least one of the sub-bands using a key to produce encrypted sub-band data; and transmitting the encrypted sub-band data to a recipient separately from the other sub-bands.
    Type: Application
    Filed: April 9, 2004
    Publication date: November 11, 2004
    Inventor: Atam P. Dhawan
  • Patent number: 6778670
    Abstract: A method and apparatus are provided for encrypting a stream of data transmitted within a frame. The method includes determining a first initialization state in a first preselected interval, and determining the first initialization state in a second preselected interval, wherein the second preselected interval is less than the first preselected interval. The method includes generating a key stream in response to determining the first initialization state in the second preselected interval, and encrypting at least one bit of the stream of data with at least one bit of the key stream.
    Type: Grant
    Filed: August 13, 1999
    Date of Patent: August 17, 2004
    Assignee: Legerity, Inc.
    Inventors: Sandhya Sharma, Jagannathan Bharath, David N. Larson
  • Publication number: 20040086122
    Abstract: The invention provides a method of recovering from de-synchronization attacks includes registering original and altered digital content using nonlinear transformations to iteratively attempt to provide better-approximated registration. Approximation occurs at more than one level of granularity, by selecting among a greater number of possible transformation functions at each step. Transformations and comparisons might be conducted directly on pixel values, on coefficients for a set of basis wavelets, or on some transformation of the original and altered digital content. A human operator might assist this process, such as by suggesting transformations or providing evaluation of the degree of registration. Upon resynchronization, embedded identifying information in the original digital content is recovered.
    Type: Application
    Filed: February 28, 2003
    Publication date: May 6, 2004
    Applicant: Kaleidescape, a corporation
    Inventor: Stephen Watson
  • Patent number: 6654885
    Abstract: The system checks whether authorization exists for at least two data processing devices to exchange data with one another. In the preferred embodiment, both data processing devices are of identical design. Check data are simultaneously produced, in response to a trigger signal, in both data processing devices. The check data are compared with one another in the data processing device to which a control function has been allocated.
    Type: Grant
    Filed: December 16, 1999
    Date of Patent: November 25, 2003
    Assignee: Infineon Technologies AG
    Inventor: Wolfgang Pockrandt
  • Patent number: 6560338
    Abstract: A method and an apparatus for generating encryption stream ciphers are based on a recurrence relation designed to operate over finite fields larger than GF(2). A non-linear output can be obtained by using one or a combination of non-linear processes to form an output function. The recurrence relation and the output function can be selected to have distinct pair distances such that, as the shift register is shifted, no identical pair of elements of the shift register are used twice in either the recurrence relation or the output function. Under these conditions, the recurrence relation and the output function also can be chosen to optimize cryptographic security or computational efficiency. Moreover, it is another object of the present invention to provide a method of assuring that the delay that results for the encryption process does not exceed predetermined bounds.
    Type: Grant
    Filed: February 8, 1999
    Date of Patent: May 6, 2003
    Assignee: Qualcomm Incorporated
    Inventors: Gregory G. Rose, Roy Franklin Quick, Jr.
  • Publication number: 20030048902
    Abstract: A method for scrambling and descrambling a data bitstream of an ATM cell using a computer device in which a recursion number and a bit number are stored. The method comprises the steps of sequentially storing a plurality of bits of an initial and a data bitstream, wherein the number of the bits of the initial bitstream is equal to the recursion number, carrying out a logic operation in parallel of a first and second group of the successively stored bits to derive a third group of resulting bits, wherein the numbers of the bits in each of the three groups are equal to the bit number, and the first bits in the first and second group are the first bits of the initial and data bitstream respectively.
    Type: Application
    Filed: May 24, 2002
    Publication date: March 13, 2003
    Inventor: Shih-Chi Wu
  • Publication number: 20020122557
    Abstract: A first-stage processing section 105 detects a plurality of slot timings corresponding to a plurality of correlation values equal to or greater than a threshold value, a second-stage processing section 110 detects scrambling code timing and a scrambling code group in accordance with one of the slot timings, a third-stage processing section 115 identifies a scrambling code in accordance with the scrambling code timing, and a controller 104 switches a switch 103 so that processing by the second-stage processing section 110 and processing by the third-stage processing section 115 are executed for a plurality of slot timings each time processing by the first-stage processing section 105 is executed once.
    Type: Application
    Filed: February 7, 2002
    Publication date: September 5, 2002
    Inventors: Koichi Aihara, Junji Somon, Satoshi Imaizumi, Noriaki Minamida, Hidetoshi Suzuki
  • Patent number: 6408077
    Abstract: In a device for descrambling scrambled digital data, the digital data are grouped into parallel combinations of bits before being descrambled. The combinations of bits are descrambled and then split back into a serial stream of bits.
    Type: Grant
    Filed: February 3, 1998
    Date of Patent: June 18, 2002
    Assignee: Thomson Licensing SA.
    Inventor: Jacques Prunier
  • Patent number: 6385319
    Abstract: The present invention comprises the bus reset detection circuit 6 detecting a bus reset signal from the network initiation/control state machine, the bus reset identification code generation circuit 8 and the bus reset identification code detection circuit 11 detecting a bus reset identification code and the bus reset signal generation circuit 16 which outputs a bus reset signal to the network initiation/control state machine.
    Type: Grant
    Filed: December 8, 1998
    Date of Patent: May 7, 2002
    Assignee: NEC Corporation
    Inventor: Takayuki Nyu
  • Patent number: 6215876
    Abstract: An apparatus and method for detecting erroneous initialization vectors transmitted over a communications channel and maintaining cryptographic synchronization by comparing a received vector with a predicted correct vector. The vectors are random-like in nature by utilizing a pseudo-random number generator having a long overall cycle length. If the level of bit errors of the comparison is relatively small, considering the predicted vector is considered correct and used for synchronization, but if the number of bit errors of the comparison is relatively large, the predicated vector is considered in correct.
    Type: Grant
    Filed: December 31, 1997
    Date of Patent: April 10, 2001
    Assignee: Transcrypt International, Inc.
    Inventor: James E. Gilley