Mutual (reciprocal) Synchronization Patents (Class 370/507)
  • Patent number: 8140702
    Abstract: A method is provided for maximizing utility of a media delivery network having a media source, a first media adaptor, a second media adaptor and a media renderer. The media source can provide data in a first format and a second format. The first media adaptor can receive the data in the first format from the media source. The second media adaptor can receive the data in the second format from the media source. The first media adaptor can further provide data in a third format based on the received data in the first format. The second media adaptor can further provide data in a fourth format based on the received data in the second format. The media renderer can render the data in the third format and can render the data in the fourth format.
    Type: Grant
    Filed: December 28, 2009
    Date of Patent: March 20, 2012
    Assignee: General Instrument Corporation
    Inventors: Yong Wang, Rohit S. Bodas, Faisal Ishtiaq
  • Patent number: 8130795
    Abstract: A communication system includes devices configured to communicate with each other via wireless communication by exchanging information in a sequence of time slots in frames. These time slots may be synchronized across the devices using distributed mutual synchronization in which each device exchanges time stamps in the frames with other devices to stabilize clock signals in the devices about a common frequency. Moreover, a time stamp in a given time slot may be generated by a transmitting device, which is transmitting in the given time slot, based on a clock signal in the transmitting device.
    Type: Grant
    Filed: October 24, 2008
    Date of Patent: March 6, 2012
    Assignee: Palo Alto Research Center Incorporated
    Inventor: Marc Mosko
  • Patent number: 8107503
    Abstract: A method of synchronizing data between two devices can include starting, in a first device, a first synchronization operation comprising transmitting a first data set to be received by a second device, the first data set comprising changes to multiple different data elements in the first device that have occurred since a prior successful synchronization operation between the first device and the second device; receiving at least one of separate acknowledgements for each of the multiple different data elements, each such acknowledgement indicating that a change to one of the multiple different data elements in the first device has been applied to a corresponding data element in the second device; and when the first synchronization operation is interrupted, initiating a second synchronization operation to synchronize the changes of the first data set for which a separate acknowledgement was not received during the first synchronization operation.
    Type: Grant
    Filed: March 18, 2010
    Date of Patent: January 31, 2012
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Sidd Goyal, Mikhail Ryleev
  • Patent number: 8095161
    Abstract: A method for determining a transmission timing is provided. The method includes steps of, at a first point in time, determining a first transmission timing for transmissions from a user entity to a first radio transceiver, and determining a representation of a first position of the user entity in relation to the first radio transceiver and at least a second and a third radio transceiver. The method further includes, at a second point in time, subsequent to the first point in time, determining a representation of a second position of the user entity in relation to the first, second and third radio transceivers, and adjusting the transmission timing based on a difference of the first position and the second position.
    Type: Grant
    Filed: August 26, 2009
    Date of Patent: January 10, 2012
    Assignee: Huawei Technologies Co., Ltd.
    Inventor: David Sandberg
  • Patent number: 8082367
    Abstract: In a utility monitoring system, a network of intelligent electronic devices (IEDs), including a master IED that receives master clock information from a global positioning system, includes a differential time synchronization (DTS) algorithm for automatically adjusting the corresponding clocks of each of the IEDs to be synchronized with the master clock information. A controller coupled to the network communicates instructions to the IEDs to collect frequency variation data. A known data alignment algorithm determines a point of alignment between two sets of frequency variation data, and the controller determines based on the data alignment algorithm output a time differential representing a time offset between the IED's clock and the master clock information. The time differential is communicated to the target IED, which advances or retards its clock based on the time differential.
    Type: Grant
    Filed: July 23, 2009
    Date of Patent: December 20, 2011
    Assignee: Schneider Electric USA, Inc.
    Inventors: Hal Etheridge, Douglas Scharmann
  • Patent number: 8081664
    Abstract: The invention relates to a method and an arrangement for regenerating a timing signal in digital data communication where two network elements operate in a master/slave loop timing mode. In a solution according to the invention two different frequency difference indicators are formed. Values or changes of the values of both of them in relation to time indicate a frequency difference between a reference timing signal present in a master device and a regenerated timing signal present in a slave device. One frequency difference indicator is formed on the basis of reception taking place in the master device, and the other one on the basis of reception taking place in the slave device. The frequency of the regenerated timing signal is adjusted utilizing information contained by both frequency difference indicators. The probability of incorrect frequency adjustment measures can be thereby reduced.
    Type: Grant
    Filed: April 7, 2006
    Date of Patent: December 20, 2011
    Assignee: Tellabs Oy
    Inventor: Mikko Laulainen
  • Patent number: 8082371
    Abstract: The invention describes a method for the monitoring and management of data traffic in a communication system with several communication nodes which communicate via interfaces monitored by a bus monitor, comprising the following steps: a) provision of a predefined communication time schedule for all communication nodes, b) initialization of the bus monitor, c) synchronization of the communication time schedule of the bus monitor with the predefined communication time schedule executed by the communication nodes in a distributed arrangement, the synchronization taking place on the basis of activities observed at the interfaces, d) monitoring of the activities of the communication nodes by the bus monitor, e) comparison of the activities with the predefined communication time schedule, and f) deactivation of the interface for any communication node for which an activity not compatible with the predefined communication time schedule has been detected. A circuit arrangement and its use are also described.
    Type: Grant
    Filed: February 13, 2003
    Date of Patent: December 20, 2011
    Assignee: NXP B.V.
    Inventors: Manfred Zinke, Patrick Willem Hubert Heuts, Peter Fuhrmann
  • Patent number: 8050881
    Abstract: A system for synchronizing data after they are collected and stored locally in sensor units in a distributed sensor system, so that wired or wireless communication is not required during a data-collection session. Each sensor unit has a local clock providing local-clock times before and after a data-collection session, and a data processor uses its local clock or a sensor unit's local clock as the reference to compute each sensor unit's time-scaling factor, which is the ratio of the elapsed reference local-clock time and the elapsed local-clock time. The data processor uses the time-scaling factor to convert each sensor unit's local-clock data-sampling times to the reference local-clock data-sampling times, and the data processor subsequently interpolates sensor data to approximate simultaneous sensor-data values at desired reference local-clock times. A physical-activity monitoring system can use this synchronization method to reduce the size, power consumption, and cost of the sensor units.
    Type: Grant
    Filed: October 1, 2008
    Date of Patent: November 1, 2011
    Assignee: Enbiomedic
    Inventors: King-Wah Walter Yeung, Wei-Wei Vivian Yeung
  • Patent number: 8041979
    Abstract: A method of synchronizing respective state transitions in a group of devices including at least one responding device is disclosed. The group of devices is communicatively coupled to an initiating device via a communication network. The method includes the at least one responding device receiving a trigger message from the initiating device. The trigger message includes a state transition time or a time from which a state transition time is obtainable. The method further includes the at least one responding device jointly making a respective state transition at the state transition time. A responding device, and a system including the initiating device and the responding device are also disclosed.
    Type: Grant
    Filed: October 29, 2007
    Date of Patent: October 18, 2011
    Assignee: Agilent Technologies, Inc.
    Inventors: James Adam Cataldo, Bruce Hamilton
  • Patent number: 8040859
    Abstract: A location of node i in a network having a plurality of nodes is identified by intersecting regions that are guaranteed to contain the node i with respect the other nodes that are neighbors of the node i and iteratively minimizing the size of the intersection region containing the node i.
    Type: Grant
    Filed: February 17, 2006
    Date of Patent: October 18, 2011
    Assignee: Honeywell International Inc.
    Inventors: Atish Datta Chowdhury, Koushik Sinha
  • Patent number: 8031694
    Abstract: A system and method for flexible data provision to mobile communication devices, which enables the user to selectively download data to the mobile communication device from a remote computer. The selective data download may optionally apply to one or more of a single item of data, to multiple items of data, one or more categories of data and the like. Preferably, the user interface provided through the remote computer comprises a mark-up language document, such as a Web page for example.
    Type: Grant
    Filed: February 8, 2008
    Date of Patent: October 4, 2011
    Assignee: Amdocs Software Systems Limited
    Inventors: Yoad Gidron, Rafael Ton
  • Patent number: 8019228
    Abstract: An optical transmission system capable of time difference correction without increasing guard times, thereby improving optical packet transmission efficiency. An optical switching processor sets identical switching timing for input ports thereof such that optical signals input from the input ports are switched at the same timing. During initialization, a time difference corrector transmits an optical dummy packet to an optical switch node, and detects synchroneity of the optical dummy packet returned thereto after being switched by the optical switch node. If synchronization error is detected, the time difference corrector adjusts the output timing of the optical dummy packet so that the timing of arrival of the optical dummy packet at the optical switching processor may coincide with the switching timing of the optical switching processor, to thereby correct the time difference between the switching timing and the arrival timing.
    Type: Grant
    Filed: November 16, 2007
    Date of Patent: September 13, 2011
    Assignee: Fujitsu Limited
    Inventors: Kyosuke Sone, Yasuhiko Aoki
  • Patent number: 8018972
    Abstract: The invention is directed to a method and apparatus for providing improved packet over timing clock synchronization in a packet switching network using Operations, Administration, and Maintenance (OAM) tools to compensate for asymmetrical characteristics between forward and reverse data paths.
    Type: Grant
    Filed: June 30, 2009
    Date of Patent: September 13, 2011
    Assignee: Alcatel Lucent
    Inventors: Peter Roberts, Kin-Yee Wong
  • Patent number: 7995623
    Abstract: A method and system for adjusting a clock signal in a network element of a data network adjusts the clock signal based on difference values formed by received synchronizing messages. Each difference value is a difference of a reception and transmission values of a received synchronizing message. The reception value depends on a cumulated number of periods of the clock signal at a moment of arrival of the synchronizing message. The transmission value depends on a position of the synchronizing message in a chronological transmission order of synchronizing messages. When adjusting, an adjusting effect of the difference values belonging to a lower part of a margin of fluctuation of the difference values is weighted more heavily than that of an upper part. Thus, for clock signal adjustment, that share of information represented by the received synchronizing messages that has the least interference is used, irrespective of the data network load.
    Type: Grant
    Filed: December 4, 2007
    Date of Patent: August 9, 2011
    Assignee: Tellabs Oy
    Inventors: Kenneth Hann, Heikki Laamanen, Mikko Laulainen
  • Patent number: 7983209
    Abstract: A system and method for converting a schema based synchronous service to a schema based asynchronous service. The asynchronous service for implementing on a server configured for communication with a respective client over a network. The system and method comprising a subscription module for identifying a port type with each notification method added to a description of the synchronous service and for associating a subscription operation with the identified port type. The system and method can also include an artifact module for generating at least one conversion artifact related to the added notification method, the conversion artifact configured for use by a developer to assist in developing the supporting clients of the asynchronous service as well as the asynchronous service itself. The system and method can also include an integration module for combining the notification methods and subscription operations and conversion artifacts to produce a description of the asynchronous service.
    Type: Grant
    Filed: April 18, 2005
    Date of Patent: July 19, 2011
    Assignee: Research In Motion Limited
    Inventors: Bryan Goring, Brindusa Fritch, Viera Bibr
  • Patent number: 7969993
    Abstract: Synchronization of presence information is established between different presence services. Presence information of each user is stored on the presence server 27 of the presence display system comprising mobile phones. Presence information of the SIP phone system comprising the SIP phone 29 and the SIPG/W (enterprise side) 30 is stored in the SIPG/W (enterprise side) 30. When presence information of the presence server 27 has changed, the presence server 27 notifies the SIPG/W (enterprise side) 30 of the change in presence information via the SIPG/W (mobile communication network side) 31. Conversely, when presence information of the SIP phone system has changed, the SIPG/W (enterprise side) 30 notifies the presence server 27 of the change in presence via the SIPG/W (mobile communication network side) 31.
    Type: Grant
    Filed: November 11, 2004
    Date of Patent: June 28, 2011
    Assignee: Vodafone Group PLC
    Inventors: Koichi Shimamura, Jota Nakatsuma, Seiichi Kawakami, Takenori Sekiya
  • Patent number: 7957336
    Abstract: A system for locating a client in a wireless network. The system includes at least three access points. Each access point is adapted to wirelessly communicate with a client having a location using packeted data, be placed in wired data communication within a selected data network; and to share a common precise time reference using the selected data network. The system further includes a switch adapted to translate the relative position of the access points based on a shared common precise time reference and to calculate the location of the client based on a transmission from the client.
    Type: Grant
    Filed: January 5, 2009
    Date of Patent: June 7, 2011
    Assignee: Cisco Technology, Inc.
    Inventors: James A. Amos, Clark Carty
  • Patent number: 7953066
    Abstract: Data is transmitted via time division multiple access methods and every radio cell includes one base station each for the radio coverage of a plurality of mobile stations assigned to the radio cell. The base station receives, in addition to mobile station signals of its own radio cell, mobile station signals of neighboring radio cells and determines, on the basis of the mobile station signals received, a time synchronization value and/or a frequency synchronization value to which the base station synchronizes itself.
    Type: Grant
    Filed: July 20, 2009
    Date of Patent: May 31, 2011
    Assignee: Siemens Aktiengesellschaft
    Inventors: Elena Costa, Dirk Galda, Harald Haas, Niclas Meier, Hermann Rohling, Egon Schulz
  • Patent number: 7933296
    Abstract: Systems and methods for sharing and synchronizing data using the addition of synchronization data to a feed that contains data items, and at least a node or endpoint that provides synchronization-related services to other endpoints, are disclosed. Such systems and methods, and client and service endpoints, may use the added synchronization data in multiple ways to share data, incorporate changes consistently, and resolve conflicts.
    Type: Grant
    Filed: March 2, 2007
    Date of Patent: April 26, 2011
    Assignee: Microsoft Corporation
    Inventors: Matthew S. Augustine, Arnold N. Blinn, John D. Elliott, Don M. Gillett
  • Patent number: 7924807
    Abstract: A method for synchronizing communicating entities in a decentralized network. The method begins with a recipient entity receiving data comprising a first timestamp and a first distance. The first timestamp being the time the first data was broadcast; the first distance being a distance from the sender's synchronization time. Next the recipient entity receives data comprising a second timestamp and a second distance. The second timestamp being the time the second data was broadcast; the second distance being a distance from the sender's synchronization time. Based on the first and second timestamps and distances, the recipient entity calculates a new synchronization time. Next, the recipient entity broadcasts to at least one entity in the decentralized network data comprising a third timestamp and a third distance. The third timestamp being the time the third data was broadcast; the third distance being a distance from the recipient entity's synchronization time.
    Type: Grant
    Filed: December 5, 2008
    Date of Patent: April 12, 2011
    Assignee: International Business Machines Corporation
    Inventors: Frederic Bauchot, Jean-Yves Clement, Gerard Marmigère, Joaquin Picon
  • Patent number: 7903694
    Abstract: A device is disclosed for transmitting packets in a packet communication network comprising at least two stations, including in particular means for generating a first timestamp from a sampled value of a master counter, means for generating a second timestamp from a sampled value of a second counter synchronized on the at least two stations and means for transmitting jointly the two timestamps in the packet communication network. A device is further disclosed for receiving packets in a packet communication network, which uses the double timestamp generated by the transmitter device.
    Type: Grant
    Filed: March 12, 2007
    Date of Patent: March 8, 2011
    Assignee: Thomson Licensing
    Inventors: Serge Defrance, Thierry Tapie, Gael Mace
  • Patent number: 7903601
    Abstract: An ad hoc method is provided for synchronizing a wireless network. The method involves broadcasting a first signal including a join message from a first node (FN). The method also involves saving a first timestamps in a memory device internal to the FN after broadcasting the first signal. The method further involves generating a signal including a join response message after receiving the first signal. The join response message is comprised of a second timestamp indicating a local time during which the first signal was received at the second node (SN). The method also includes the step of determining an initial time offset by computing a difference between the first timestamp and the second timestamp. The method further includes the steps of generating a request to send (RTS) message at the FN. The FN uses the initial time offset in conjunction with the RTS message to asynchronously communicate with the SN.
    Type: Grant
    Filed: November 8, 2007
    Date of Patent: March 8, 2011
    Assignee: Harris Corporation
    Inventors: Paul Voglewede, Scott J. Cloutier, Todd W. Joslin, Peter J. Roth, Adam R. Kent
  • Patent number: 7885671
    Abstract: A system and method for state synchronization between a base station and a mobile station in a mobile communication system. A count value indicative of a state change of the base station is received. The received current count value is compared with a previous count value previously received and stored. If the current count value is different from the previous count value, the mobile station performs a network entry procedure with the base station.
    Type: Grant
    Filed: July 6, 2006
    Date of Patent: February 8, 2011
    Assignee: Samsung Electronics Co., Ltd
    Inventors: Yeong-Moon Son, Hong-Sung Chang, Pan-Yuh Joo, Jung-Je Son, Jae-Weon Cho, Mi-Hyun Lee, Hyun-Jeong Kang, Song-Nam Hong, Sung-Jin Lee, Hyoung-Kyu Lim, Young-Ho Kim
  • Patent number: 7869420
    Abstract: Methods and systems are provided for in-band signaling of at least two simultaneous digital media streams in a network, the two simultaneous streams being a part of a media session. Each of the at least two simultaneous streams is generated from a corresponding source. The generated simultaneous streams are synchronized by using a unique marker packet. Each synchronized stream is transmitted to a destination corresponding to each source.
    Type: Grant
    Filed: November 16, 2005
    Date of Patent: January 11, 2011
    Assignee: Cisco Technology, Inc.
    Inventors: James Tighe, Frank Roland Zerangue, Jr., Rowan McFarland
  • Patent number: 7855994
    Abstract: In a mobile communication system, multiple transceivers perform radio communications in the same frequency band.
    Type: Grant
    Filed: April 26, 2006
    Date of Patent: December 21, 2010
    Assignee: NTT DoCoMo, Inc.
    Inventors: Hiromasa Fujii, Takatoshi Sugiyama, Hitoshi Yoshino
  • Patent number: 7848361
    Abstract: A time-triggered communication system in a dual-channel network of singlechannel architecture, wherein in each case one communication controller (2, 6) is assigned to one channel, and two corresponding communication controllers (2, 6) communicate with one another via an inter-channel interface (1a, 1b). Said inter-channel communication contains information about limiting points (G1, G2 . . . G12) of a time path. A limiting point (G1, G2 . . . G12) is, for example, the point in time when a cycle starts. The interchange of limiting points enables the temporal offset of the two channels to be determined as well as a correction value. After every two cycles also the rate error of the local clocks can be ascertained and a suitable correction value determined. The reliability of safety-relevant networks is increased by the time-triggered communication system described hereinabove.
    Type: Grant
    Filed: May 10, 2004
    Date of Patent: December 7, 2010
    Assignee: NXP B.V.
    Inventors: Jörn Ungermann, Peter Fuhrmann
  • Patent number: 7840711
    Abstract: A synchronous communication device for processing communication synchronously among a plurality of information terminals connected to a communication line, comprising: judging means for judging whether or not the plurality of information terminals connected to the communication line are in a normal communication state; input information setting means for, when on the basis of the result from the judging means judgment is made that an anomaly has occurred in at least one information terminal among the plurality of terminals and that synchronization of the one information terminal with another information terminal among the plurality of terminals is not possible, setting as assumed input information the input information of the synchronization immediately prior to the synchronization in which synchronization is not possible; and computing means for, on the basis of the assumed input information set by the input information setting means, determining the synchronization state of the synchronization in which sync
    Type: Grant
    Filed: April 17, 2007
    Date of Patent: November 23, 2010
    Assignee: Mediaseek Inc.
    Inventors: Hajime Otoshi, Atsushi Ichinari
  • Patent number: 7826492
    Abstract: A communication system carrying out an isochronous transfer, includes a cycle master node and nodes connected with each other through a system bus. The cycle master node sets a cycle time of the isochronous transfer and transfers a cycle start packet onto the system bus for every the cycle time. Each of the nodes transfers an isochronous packet onto the system bus in response to the cycle start packet.
    Type: Grant
    Filed: May 25, 2006
    Date of Patent: November 2, 2010
    Assignee: NEC Electronics Corporation
    Inventor: Junichi Takeuchi
  • Patent number: 7813382
    Abstract: A method of synchronizing a network includes transmitting a tone signal to convey time information and setting a local time according to the conveyed time information. The method may also include detecting an occurrence of a predefined aspect of the tone signal, and setting a local time based on the occurrence of the predefined aspect of the signal.
    Type: Grant
    Filed: September 30, 2005
    Date of Patent: October 12, 2010
    Assignee: Robert Bosch GmbH
    Inventors: Arati Manjeshwar, Lakshmi Venkatraman, Bhaskar Srinivasan
  • Patent number: 7801108
    Abstract: Methods and apparatuses for establishing time at a first basestation, and synchronizing the first basestation with other basestations in a cellular network. The method may be performed using a mobile (cellular communication) station that includes a satellite position system receiver. One method comprises determining a location of the mobile station, determining a time indicator that represents a time-of-day at the mobile station, wherein the time indicator is determined relative to a signal available at the first basestation, transmitting at least one of the position information and location, and transmitting the time indicator from the mobile station. The time indicator and at least one of the position information and the location are used to establish a time at the first basestation such that the first basestation is synchronized to other basestations in the cellular communication system. Other methods and apparatuses are also described for synchronizing basestations in a cellular network.
    Type: Grant
    Filed: January 29, 2007
    Date of Patent: September 21, 2010
    Assignee: QUALCOMM Incorporated
    Inventors: Norman F Krasner, Edward V Jolley
  • Patent number: 7792233
    Abstract: A packet preamble search method is disclosed for locating a packet preamble with multiple predetermined patterns of a regular form within a received transmission signal with sequential multiple patterns. The pattern of the received transmission signal and the predetermined pattern of the packet preamble have the same length with even bits. The pattern of the transmission signal is sequentially compared with the predetermined pattern. A hit count is increased and a miss count is reset when the pattern of the transmission signal matches the predetermined pattern. The miss count is increased and the hit count is decreased when the pattern of the transmission signal does not match the predetermined pattern. The hit count and the miss count are reset when the hit count is less than or equal to the miss count. An address matching procedure is activated when the hit count exceeds or is equal to a threshold value.
    Type: Grant
    Filed: July 3, 2006
    Date of Patent: September 7, 2010
    Assignee: Princeton Technology Corporation
    Inventors: Jia-Yu Yang, Wen-Jan Lee, Kwo-Wei Chang
  • Patent number: 7738505
    Abstract: A method and system for synchronizing transmission/reception timings delayed during transmission/reception of data frames for voice signals in a mobile communication system including a media gateway with a transcoder and a base station controller for exchanging digital voice signals with the media gateway. The media gateway or the base station controller performs synchronization control by detecting synchronization of forward data frames for the voice signals. As the base station controller requests synchronization, the media gateway adjusts transmission timing and acquires synchronization according to the adjusted transmission timing, thereby correctly transmitting/receiving data frames for the voice signals.
    Type: Grant
    Filed: July 12, 2004
    Date of Patent: June 15, 2010
    Assignee: Samsung Electronics Co., Ltd
    Inventor: Yong Chang
  • Patent number: 7724783
    Abstract: A method is provided for receiving a data frame in an ultrawide bandwidth network. In this method, a device receives an ultrawide bandwidth signal containing a data frame. The device then performs an acquisition operation during a first preamble in the data frame, and identifies a marker after the first preamble that indicates that the first preamble has ended. After this, the device performs a signal processing operation during a second preamble in the data frame. After the training, the device then receives a header in the data frame, and then receives a payload in the data frame. By having a marker between the two preambles, this method provides a receiving device with critical information regarding the timing of the preamble section of a frame.
    Type: Grant
    Filed: February 27, 2004
    Date of Patent: May 25, 2010
    Assignee: Freescale Semiconductor, Inc.
    Inventors: William M. Shvodian, John W. McCorkle, Paul R. Runkle, Timothy R. Miller, Matthew L. Welborn, Douglas E. Price, Adrian R. Macias, Richard D. Roberts, Deepak M. Joseph
  • Patent number: 7715444
    Abstract: A method of synchronizing data between two devices can include starting, in a first device, a first synchronization operation comprising transmitting a first data set to be received by a second device, the first data set comprising changes to multiple different data elements in the first device that have occurred since a prior successful synchronization operation between the first device and the second device; receiving at least one of separate acknowledgements for each of the multiple different data elements, each such acknowledgement indicating that a change to one of the multiple different data elements in the first device has been applied to a corresponding data element in the second device; and when the first synchronization operation is interrupted, initiating a second synchronization operation to synchronize the changes of the first data set for which a separate acknowledgement was not received during the first synchronization operation.
    Type: Grant
    Filed: February 2, 2007
    Date of Patent: May 11, 2010
    Assignee: Palm, Inc
    Inventors: Sidd Goyal, Mikhail Ryleev
  • Patent number: 7698395
    Abstract: A method for controlling start-up of a network is provided. The method includes receiving a message from one node of a plurality of nodes at a hub while the network is in an unsynchronized state, relaying the message to the other nodes of the plurality of nodes of the network independent of the content of the message, and blocking all messages from the one node of the plurality of nodes until a relaying condition is met.
    Type: Grant
    Filed: November 19, 2004
    Date of Patent: April 13, 2010
    Assignee: Honeywell International Inc.
    Inventors: Brendan Hall, Kevin R. Driscoll
  • Patent number: 7680154
    Abstract: A method includes determining a network counter value indicative of a network clock time of a system at a first time instant and a second time instant occurring later in time than the first time instant. The method further includes determining an audio counter value indicative of an audio clock time of the system at a third time instant occurring the first and second time instants and a fourth time instant occurring later in time than the second time instant. The method further includes determining an offset based upon the determined network counter values and the audio counter values. The method further includes adjusting the audio clock time based upon the determined offset to synchronize operation of at least one audio component operating according to the audio clock with at least one audio component operating according to the network clock. An associated system is also disclosed.
    Type: Grant
    Filed: December 31, 2007
    Date of Patent: March 16, 2010
    Assignee: Intel Corporation
    Inventors: Kevin Stanton, Frank Hady
  • Patent number: 7664144
    Abstract: A synchronization system and method for use in a packet switched communication network are provided. The synchronization system comprises a transmitter-identification system, a packet-boundary detection system and a storage-access system. The transmitter-identification system enables each receiving terminal within the network to know the identity of the originating transmitter terminal for a given packet of information, prior to the reception of this packet of information. The packet-boundary detection system enables detection of packet synchronization parameters for all transmitter-receiver pairs of terminals within the network. The storage-access system stores the detected packet synchronization parameters and allows the receiver to access the packet synchronization parameters.
    Type: Grant
    Filed: December 21, 2006
    Date of Patent: February 16, 2010
    Assignee: Edgewater Computer Systems, Inc.
    Inventors: John Fanson, Yu Wang
  • Patent number: 7656908
    Abstract: The present invention is a system and method for enabling multicast synchronization of initially unicasted content. Multiple unicast streams are synchronized in order to convert the unicast streams into a multicast stream. Each unicast stream may be accelerated or slowed down in relation to a reference stream to a common point within each stream upon which the unicast streams are replaced by a multicast stream of the same content.
    Type: Grant
    Filed: September 30, 2005
    Date of Patent: February 2, 2010
    Assignee: AT&T Corp.
    Inventor: Lee Begeja
  • Patent number: 7656906
    Abstract: In one embodiment, an electronic system comprises a first backplane for distributing timing signals, power, and control signals to electronic circuitry coupled to the first backplane, wherein the first backplane comprises a first clock module for generating the timing signals, a second backplane for distributing timing signals, power, and control signals to electronic circuitry coupled to the second backplane, wherein the second backplane comprises a second clock module for generating the timing signals, and an electrical connector coupling the first clock module to the second clock module for communication of a timing signal, wherein the first clock module comprises a circuit for detecting the presence of the electrical connector, the first clock module providing the timing signal to an output port coupled to the electrical connector in response to the circuit, and the second clock module synchronizes to the timing signal communicated via the electrical connector.
    Type: Grant
    Filed: January 21, 2005
    Date of Patent: February 2, 2010
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Daniel Wissell, Cynthia Murray
  • Patent number: 7652985
    Abstract: A data transmission system and method and a method of selecting a communication path for a dual-controller system are provided, which are applied in a first controller and a second controller of the dual-controller system. First of all, a corresponding transmission medium is selected according to a feature of a data request issued by a controller, then the data request is converted into a data format compatible with a medium interface corresponding to the selected transmission medium and is sent to a corresponding medium driving portion connected with the medium interface, and the data request is sent to another controller through the medium driving portion and a connected corresponding medium controller, so as to select a path of the highest transmission performance, and realize the data transmission between the two controllers.
    Type: Grant
    Filed: February 21, 2007
    Date of Patent: January 26, 2010
    Assignee: Inventec Corporation
    Inventors: Xiang-Bin Meng, Tom Chen, Win-Harn Liu
  • Patent number: 7649968
    Abstract: A timing system is disclosed for use in a wireless communication system that includes wireless transceiver and a digital baseband processing system. The timing system includes a primary clock generation system that provides a low frequency clock that is used as the reference clock for a digital signal processing system, which generates low frequency timing signals, and a secondary clock generation system that provides a high frequency clock that is used by the wireless transceiver to produce high resolution timing signals to control the timing of the wireless transceiver. The high resolution timing signals are commenced responsive to a low resolution timing signal.
    Type: Grant
    Filed: November 10, 2005
    Date of Patent: January 19, 2010
    Assignee: Mediatek Inc.
    Inventors: Thomas Barber, Aiguo Yan, Palle Birk, Pier Bove
  • Patent number: 7639716
    Abstract: A method for determining clock skew in a packet-based telephony session is disclosed. A telephony device receives RTCP SR packets from a remote telephony device transmitting RTP packets in a telephony session. Each control packet includes an NTP time-stamp and a RTP time-stamp. The device determines from two or more of the received SR packets a first relative rate of a remote media card clock to the remote system clock rate. Further, the device determines from two or more transmitted RTCP SR packets, a second relative rate of a local media card clock to the local system clock rate. The device can then be adjusted to take into account the first and second relative rates for optimum buffer management and to more accurately adjust the quality of a session based on one-way packet delay.
    Type: Grant
    Filed: June 18, 2004
    Date of Patent: December 29, 2009
    Assignees: University College Dublin, National University of Ireland, Dublin, National University of Ireland, Galway
    Inventors: Liam Murphy, Hugh Melvin
  • Patent number: 7623551
    Abstract: When a current synchronization between a first device and a second device is commenced, a last anchor for the current synchronization to an initialization time of a previous synchronization between the first device and the second device, and a next anchor for the current synchronization is set to an initialization time of the current synchronization. Then, a set of data elements to be synchronized during the current synchronization is determined. Typically, the set includes only those data elements that have been modified after the last anchor and up to (e.g., before or equal to) the next anchor. When the set of modified data elements is received on the second device from the first device, a device modified timestamp (DMT) for the set of data elements on the second device is set to the next anchor instead of to the current time at which the data elements are received.
    Type: Grant
    Filed: May 20, 2004
    Date of Patent: November 24, 2009
    Assignee: International Business Machines Corporation
    Inventors: Stephen T. Auriemma, Ashok C. Mammen
  • Patent number: 7620409
    Abstract: A wireless system having an infrastructure node and several leaf nodes in a non-redundant version or having at least two infrastructure nodes and several leaf nodes in a redundant version. Leaf nodes may individually seek out timing information in order to be in synch with an infrastructure node. Upon receipt of synch information from an infrastructure node, the respective leaf node may send data to the infrastructure node. In the case of a redundant system, primary and secondary nodes may be selected from a list of infrastructure nodes. Communications between an infrastructure node and a leaf node may occur on one of a number of channels, and the channel may be changed for communications between the nodes. In the case of a redundant system, a single transmission from the leaf node is received simultaneously by the redundant infrastructure nodes.
    Type: Grant
    Filed: June 17, 2004
    Date of Patent: November 17, 2009
    Assignee: Honeywell International Inc.
    Inventors: Ramakrishna S. Budampati, Patrick S. Gonia, Soumitri N. Kolavennu
  • Patent number: 7606271
    Abstract: Each node in a communication system receives state variable signals from other nodes indicating the internal operating states or internal timing of the other nodes, and transmits a state variable signal indicating its own internal operating state or timing. Each node also determines whether each received state variable signal is valid. Transitions in the internal operating state or timing of a node take place at a basic transition rate but at times adjusted according to the valid state variable signals received from other nodes. A group of neighboring nodes transmitting data signals can thereby autonomously reach a steady state in which their data signals do not collide, without having their timing control disrupted by reflected state variable signals or other invalid state variable signals.
    Type: Grant
    Filed: March 7, 2005
    Date of Patent: October 20, 2009
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Taketsugu Yao, Masaaki Date, Yukihiro Morita, Shigeru Fukunaga
  • Patent number: 7577222
    Abstract: Methods and apparatus to determine a relative change relationship between modem and frame clocks are generally described herein. Other embodiments may be described and claimed.
    Type: Grant
    Filed: May 17, 2005
    Date of Patent: August 18, 2009
    Assignee: Intel Corporation
    Inventors: Philip P. Mathew, Baraa Al Dabagh
  • Patent number: 7570668
    Abstract: The invention relates to a method of limiting the size of synchronization messages between a first synchronization device and a second synchronization device. The first device specifies a maximum message size for synchronization messages to be sent to the first device and transmits information on the maximum message size to the second device. The second device transmits to the first device one or more synchronization messages which are equal to or smaller than the maximum message size of the first device.
    Type: Grant
    Filed: October 3, 2001
    Date of Patent: August 4, 2009
    Assignee: Nokia Corporation
    Inventors: Riku Mettälä, Jussi Piispanen, Mikko Sahinoja, Ari Sutinen
  • Patent number: 7570669
    Abstract: A system and method for determining a common time base among nodes in a network by iteratively propagating timing constraints among the nodes, and determining a time-shift to apply to the time base of each node that conforms to these constraints. “Trace” files record the time of transmission or reception of packets at each node, based on the time base at the node. A fundamental constraint in a common time-based system is that the time of reception of a packet at a destination node cannot be prior to the time of transmission of the packet from a source node. A further constraint in a common time-based system is that the time of reacting to an event cannot be prior to the time of the event.
    Type: Grant
    Filed: August 9, 2004
    Date of Patent: August 4, 2009
    Assignee: OPNET Technologies, Inc.
    Inventors: Patrick J. Malloy, Antoine D. Dunn
  • Patent number: 7561599
    Abstract: A method for providing reliable multicasting is described. A transmitted multicast packet is received at second devices, each of which in response transmits a first acknowledgement. If a second acknowledgement, which acknowledges the first acknowledgement, is not received within a predetermined time period, the first acknowledgement is retransmitted. If all first acknowledgements are not received within a preset time period, the multicast packet is retransmitted. If the retransmitted multicast packet has been received, at each of the second devices, if the second acknowledgement has not been received the first acknowledgement is retransmitted, while if the second acknowledgement has been received, the retransmitted multicast packet is ignored and no additional first acknowledgement is transmitted.
    Type: Grant
    Filed: September 19, 2005
    Date of Patent: July 14, 2009
    Assignee: Motorola, Inc.
    Inventors: Randy L. Ekl, Anthony R. Metke
  • Patent number: RE41000
    Abstract: Methods and an arrangement for synchronizing communication of framed data via asynchronous base stations (BS1, BS2) in a cellular communication system are presented. The synchronization methods are performed continuously by sending out certain system frame counter states from a central node in the system to all its connected base stations (BS1, BS2). Each base station (BS1, BS2) includes a local frame counter (LFCBS1, LFCBS2), which generates local frame counter states (t1(1)-t1(4), t2(1)-t2(4)) correlated to the system frame counter states. Transmission of information via the base stations (BS1, BS2) is synchronized by assigning each data frame (DR(1)-DR(4)) a particular frame number, which is given by the local frame counter states (t1(1)-t1(4), t2(1)-t2(4)), so that data framed (DF(1)-DF (4)) having identical numbers contain copies of a certain data packet.
    Type: Grant
    Filed: September 3, 2004
    Date of Patent: November 24, 2009
    Assignee: Telefonaktiebolaget L M Ericsson (publ)
    Inventors: Per Hans Ake Willars, Karl Anders Näsman