Patents by Inventor Louis Roberts Litwin

Louis Roberts Litwin has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20050193305
    Abstract: The disclosed embodiments relate to a technique for selecting one of several antennas or channels in a receiver based on the quality of the channel response at each of the antennas in a multicarrier system employing convolutional forward error-correction coding. Channel estimates are computed for each subcarrier and monotonic weights are assigned to each subcarrier based on the relative strength of the channel response for that subcarrier. The monotonic weights are mapped to each bit in a symbol for each subcarrier and bits are de-interleaved, if needed. A sliding window evaluation is performed to determine an overall channel quality metric for each channel. The antenna or channel having the highest overall CQM is selected to receive data.
    Type: Application
    Filed: June 28, 2002
    Publication date: September 1, 2005
    Inventors: Maxim Belotserkovsky, Vincent Demoulin, Louis Robert Litwin
  • Patent number: 6920600
    Abstract: A decoder and decoding method are described, in which a syndrome is calculated from a codeword in a syndrome generator, an error polynomial is generated based upon the syndrome in an error polynomial generator, an error location is determined from the error polynomial in the error location generator, an error magnitude is calculated from the error polynomial in the error magnitude generator and the codeword is corrected by a error corrected codeword generator responsive to location and error magnitude. An intra-decoder block messaging scheme is described in which one or more components generate inactivity messages to signal an ability to process data corresponding to a next codeword. A dual Chien search block implementation is described in which Chien block is used to determine the number of errors corresponding to a specified codeword, separately from error location and magnitude calculations performed by the Chien/Forney block.
    Type: Grant
    Filed: January 23, 2002
    Date of Patent: July 19, 2005
    Assignee: Thomson Licensing S.A.
    Inventors: Louis Robert Litwin, Jr., Didier Velez
  • Patent number: 6901252
    Abstract: According to an aspect of the present invention, a method for providing non-voice data to a mobile device includes the step of maintaining a connection between the mobile device and a base station, when a user of the mobile device terminates a voice call provided through the base station. The non-voice data is received while the connection is maintained. The connection between the mobile device and the base station is terminated, upon performing the receiving step.
    Type: Grant
    Filed: November 20, 2001
    Date of Patent: May 31, 2005
    Assignee: Thomson Licensing S. A.
    Inventor: Louis Robert Litwin
  • Patent number: 6834091
    Abstract: Synchronization of a powerline modem network (10) with a plurality of devices is provided. A plurality of devices (16 and 18) each include a powerline modem (20) and a clock circuit (22) for synchronizing a data rate. The powerline modem permits data transmission between the plurality of devices over a powerline network on data carriers (28). A synchronization signal is transmitted over the powerline network. The synchronization signal includes a carrier (30) operating at a frequency different from the data carriers. The synchronization signal provides each of the plurality of devices a time reference to synchronize the data rate.
    Type: Grant
    Filed: April 3, 2001
    Date of Patent: December 21, 2004
    Assignee: Thomson Licensing S.A.
    Inventors: Louis Robert Litwin, Jr., Kumar Ramaswamy
  • Publication number: 20040203556
    Abstract: A system and method for supporting updates of database contact information to mobile communications devices includes a system having a data entry computer for compiling database contact information for a group of mobile communications devices, a service provider computer server in signal communication with the data entry computer for uploading the database contact information into the service provider computer server and for downloading the database contact information substantially simultaneously to the group of mobile communications devices, and a mobile communications device in signal communication with the service provider computer server for receiving the database contact information and for updating its own global logical database; wherein the method for supporting updates of database contact information to mobile communications devices includes the steps of compiling database contact information for a group of mobile communications devices, uploading the database contact information to a service provid
    Type: Application
    Filed: April 12, 2002
    Publication date: October 14, 2004
    Inventor: Louis Robert Litwin
  • Patent number: 6795486
    Abstract: An apparatus and method for providing variable-length correlation for spread-spectrum communications includes a derotator, a variable-length correlator in signal communication with the derotator, a phase detector in signal communication with the variable-length correlator, a lock detector in signal communication with the phase detector, and a controller in signal communication with the lock detector for controlling the length of the variable-length correlator; where the corresponding method to track out large frequency offsets in spread-spectrum communications includes receiving signal chips, correlating the received signal chips, computing a loop error in accordance with the correlation, setting a new lock status in accordance with the computed loop error and a previous lock status, and setting a new correlator length in accordance with the new lock status and a previous correlator length.
    Type: Grant
    Filed: September 23, 2002
    Date of Patent: September 21, 2004
    Assignee: Thomson Licensing S.A.
    Inventor: Louis Robert Litwin, Jr.
  • Publication number: 20040176073
    Abstract: A method by a cellular network for notifying a caller when a called user is connected to the cellular network includes the steps of storing a phone number associated with a caller that wants to be notified when a called user is connected to the cellular network, registering the called user with the cellular network when a communication device associated with the called user becomes active on the network, and notifying the caller indicating that the communication device is active on the network responsive to the step of registering by the called user.
    Type: Application
    Filed: March 6, 2003
    Publication date: September 9, 2004
    Inventors: Louis Robert Litwin, Purvin Bibhas Pandit
  • Publication number: 20040155961
    Abstract: An apparatus for controlling display of a video camera signal received over a powerline network includes a powerline modem for receiving a video camera signal over a powerline network, a security controller for receiving detection signals indicative of a security breach condition, and a signal converter for converting said video camera signal to another format.
    Type: Application
    Filed: February 11, 2003
    Publication date: August 12, 2004
    Inventors: Louis Robert Litwin, John William Richardson, Kumar Ramaswamy
  • Publication number: 20040155757
    Abstract: An apparatus for monitoring operation of a security camera on a powerline network includes a powerline modem for coupling to a powerline network for receiving a monitoring signal from a security camera coupled to said powerline network, and a computer configured for processing said monitoring signal, determining a status of said security camera based on said processing and generating a response notifying said status based on said determining.
    Type: Application
    Filed: February 11, 2003
    Publication date: August 12, 2004
    Inventors: Louis Robert Litwin, John William Richardson, Kumar Ramaswamy
  • Publication number: 20040156349
    Abstract: An Orthogonal Frequency Division Multiplexing (OFDM) receiver that employs N second-order phase-lock loops (62-66, 74-78) sharing a common integrator (72) (where N is the number of pilots in the system). The N second order phase-lock loops (62-66), 74-78) track out independent pilot phase rotations to facilitate the constructive averaging of the pilots' phase information. At the same time by sharing a common integrator (72), the OFDM receiver takes advantage of noise averaging over multiple pilots to obtain a cleaner frequency offset estimation. The OFDM receiver may also compensate for FFT window drift by calculating (84) a phase difference between a selected pair of pilots and tracking (86) the rate of change of the calculated phase difference over time. The calculated phase difference is used to control the position of an upstream FFT window after a predetermined phase difference threshold is exceeded. The tracked rate of change is used to continuously adjust the phase of downstream equalizer taps (82).
    Type: Application
    Filed: December 16, 2003
    Publication date: August 12, 2004
    Inventors: Maxim Borisovich, Vincent Demoulin, Louis Robert Litwin Jr.
  • Patent number: 6771591
    Abstract: An Orthogonal Frequency Division Multiplexing (OFDM) receiver that compensates for FFT window drift by extracting a training symbol from a fast Fourier transformed OFDM signal, and processing the extracted training symbol to derive an FFT window adjustment factor and an associated equalizer tap initialization value. The OFDM receiver controls the position of an FFT window and the initialization of equalizer taps using the FFT adjustment factor and equalizer tap initialization value. The OFDM receiver preferably filters the fast Fourier transformed OFDM signal to remove additive channel noise and increase the likelihood of reliable equalizer tap initialization in a low SNR environment.
    Type: Grant
    Filed: July 31, 2000
    Date of Patent: August 3, 2004
    Assignee: Thomson Licensing S.A.
    Inventors: Maxim B. Belotserkovsky, Louis Robert Litwin, Jr.
  • Publication number: 20040136515
    Abstract: There is provided a method for alerting a telecommunications user that a party to a voice conference has returned from hold. The method includes the steps of detecting when a party to the voice conference has returned from a hold mode that has disengaged the voice conference, and providing an alert to a telecommunications user, in response to a result of said detecting step, informing the telecommunications user about the re-engagement of the voice conference.
    Type: Application
    Filed: January 15, 2003
    Publication date: July 15, 2004
    Inventor: Louis Robert Litwin
  • Patent number: 6754194
    Abstract: A method and apparatus for detecting the presence of a wireless local area network (WLAN) (104) detects at least one signature sequence in a radio frequency (RF) signal associated with a WLAN (104). The present invention indicates the presence of a WLAN (104) in response to the detection of the at least one signature sequence in the RF signal.
    Type: Grant
    Filed: September 13, 2002
    Date of Patent: June 22, 2004
    Assignee: Thomson Licensing S.A.
    Inventors: Kumar Ramaswamy, Louis Robert Litwin, Jr., Paul Gothard Knutson, Wen Gao, Charles Chuanming Wang
  • Publication number: 20040057498
    Abstract: An apparatus and method for providing variable-length correlation for spread-spectrum communications includes a derotator, a variable-length correlator in signal communication with the derotator, a phase detector in signal communication with the variable-length correlator, a lock detector in signal communication with the phase detector, and a controller in signal communication with the lock detector for controlling the length of the variable-length correlator; where the corresponding method to track out large frequency offsets in spread-spectrum communications includes receiving signal chips, correlating the received signal chips, computing a loop error in accordance with the correlation, setting a new lock status in accordance with the computed loop error and a previous lock status, and setting a new correlator length in accordance with the new lock status and a previous correlator length.
    Type: Application
    Filed: September 23, 2002
    Publication date: March 25, 2004
    Inventor: Louis Robert Litwin
  • Patent number: 6711221
    Abstract: An Orthogonal Frequency Division Multiplexing (OFDM) receiver detects and corrects sampling offsets in the time domain. The OFDM receiver oversamples a training sequence or symbol in a received OFDM signal, correlates the oversampled training sequence with a stored copy of a truncated version of the training sequence, locates a correlation peak, and derives a sampling offset by calculating a difference in magnitude of correlation samples in the vicinity of the correlation peak.
    Type: Grant
    Filed: February 16, 2000
    Date of Patent: March 23, 2004
    Assignee: Thomson Licensing S.A.
    Inventors: Maxim B. Belotserkovsky, Louis Robert Litwin, Jr.
  • Publication number: 20040052231
    Abstract: A method and apparatus for detecting the presence of a wireless local area network (WLAN) (104) detects at least one signature sequence in a radio frequency (RF) signal associated with a WLAN (104). The present invention indicates the presence of a WLAN (104) in response to the detection of the at least one signature sequence in the RF signal.
    Type: Application
    Filed: September 13, 2002
    Publication date: March 18, 2004
    Inventors: Kumar Ramaswamy, Louis Robert Litwin, Paul Gothard Knutson, Wen Gao, Charles Chuanming Wang
  • Publication number: 20040052232
    Abstract: A method and apparatus for detecting the presence of a wireless local area network (WLAN) (104) determines a position of a mobile device (110) using a position location system (114), receives a position of a WLAN (104) from a location database(112), and determines whether the mobile device (110) is within a service area (108) of the WLAN (104) in response to the position of the mobile device (110) and the position of the WLAN (104).
    Type: Application
    Filed: September 13, 2002
    Publication date: March 18, 2004
    Inventors: Kumar Ramaswamy, Louis Robert Litwin, Paul Gothard Knutson, Wen Gao, Charles Chuanming Wang
  • Patent number: 6704584
    Abstract: A system and method for relinquishing a network master device status in accordance with a device power reserve level includes a system having a network master device for monitoring its own power reserve level and relinquishing its network master status for that of network slave status when such level is below a threshold value, and one or more network slave devices where each such device is in signal communication with the network master device for monitoring its own power reserve level and relinquishing its network slave status for that of network master status when such level is above at least one of the threshold value and the power reserve level of the master; and further includes a corresponding method for a wireless master device to relinquish its network master status based on its power reserve level, where the method includes monitoring the power reserve level of the wireless master device, determining whether the monitored power reserve level falls below a threshold, and relinquishing the network mas
    Type: Grant
    Filed: April 16, 2002
    Date of Patent: March 9, 2004
    Assignee: Thomson Licensing S.A.
    Inventor: Louis Robert Litwin
  • Patent number: 6703923
    Abstract: A portable security device (10) for setting up secure powerline modem networks is disclosed. The portable security device includes a memory (18) which stores a protocol (19) for communicating with powerline modem devices (e.g., 22), and a socket (14) configured to receive a power cord (23) from a powerline modem device (22). A number assigning device (12 or 16) transmits a private key to powerline modem devices such that the private key is stored in the powerline modem devices and is used to associate a plurality of powerline modem devices and exclude unauthorized powerline modem devices.
    Type: Grant
    Filed: April 18, 2001
    Date of Patent: March 9, 2004
    Assignee: Thomson Licensing S.A.
    Inventors: Louis Robert Litwin, Jr., Kumar Ramaswamy, Michael Anthony Pugel
  • Patent number: 6704374
    Abstract: An Orthogonal Frequency Division Multiplexing (OFDM) receiver that detects and corrects a carrier frequency offset of a received signal is provided. The OFDM receiver samples an incoming signal in the time domain and correlates the samples with a stored version of a training or reference symbol to generate a correlation sequence. A correlation peak is detected in the correlation sequence and the index of the correlation peak is set as a reference point. The OFDM receiver acquires a sample of the incoming signal that is a predetermined distance from the reference point. Next, the phase difference between the acquired sample and the local oscillator is computed. Afterwards, the frequency of the local oscillator is adjusted to reduce the computed phase difference. The acquired sample has a known phase that is equal to the phase of the local oscillator in the absence of a carrier frequency offset.
    Type: Grant
    Filed: February 16, 2000
    Date of Patent: March 9, 2004
    Assignee: Thomson Licensing S.A.
    Inventors: Maxim B. Belotserkovsky, Louis Robert Litwin, Jr.