Abstract: A method and apparatus for data transmissions in a wireless network are disclosed. A first device may send a first frame to a second device including information regarding a number of pending data frames to be transmitted from the first device to the second device. The first device receives an acknowledgement frame including a number of approved data frames for transmission from the first device to the second device. The first device then may send a plurality of data frames without performing the contention-based channel access procedure in response to the acknowledgement frame. The first device may send a first frame to a second device for requesting data frames that are pending at the second device. The first device receives an acknowledgement frame including a number of pending and approved data frames. The first device may receive a plurality of data frames in response to the acknowledgement frame.

Abstract: Systems and methods for viewing stereoscopic television are described. The methods generate stereoscopic views from 3D content; synchronize with external view ware (e.g., shuttered glasses) to include shutter information and viewing geometry; sequence 3D content for multiple viewers at multiple perspective views; and output to a display component for viewing.

Abstract: A method is disclosed for synchronizing network subscribers in an on-board network of a vehicle, the method comprising: receiving a message dependent on a first clock present in a first network subscriber by at least one second network subscriber if a predetermined condition has been satisfied, and synchronizing a second clock in the second network subscriber on the basis of the message dependent on the first timer if the predetermined condition has been satisfied.

Abstract: An apparatus and method of controlling activation of electronic circuitry of data ports of a communication system is disclosed. One method includes a first data port detecting a lack of data for transmission to a second data port. At least one of the first data port and a second data port deactivate electronic circuitry of at least one of the first and second data ports upon detection of the lack of data. The first and second data ports maintain synchronization with each other while the electronic circuitry is deactivated by periodically exchanging synchronization test patterns. At least one of the first data port and the second data port transmit an alert to the other of the first and second data port when data for communication is detected. The other of the first data port and the second data port activate electronic circuitry upon receiving the alert. At least one of the first data port and the second data port transmit data.

Abstract: A method is disclosed for determining an operational state mismatch condition between a user equipment (UE) and a network (NW) in a 3rd generation partnership project long term evolution (3GPP LTE) network. In one embodiment, the UE can monitor messages from the NW. If the messages are not consistent with a current UE operational state, then a state mismatch is determined. In another embodiment, the UE can monitor a paging channel. If the UE receives a paging message that is not consistent with a current UE operational state, then a state mismatch is determined.

Abstract: A clock synchronization method, customer premises equipment and a clock synchronization system are provided. The customer premises equipment reads a first time stamp when receiving a first specific position of a first DMT signal sent by central office equipment; reads a second time stamp when sending a second specific position of a second DMT signal; receives a third time stamp and a fourth time stamp that are sent by the central office equipment through a data information channel. The third time stamp is read when the central office equipment sends the first specific position of the first DMT signal, and the fourth time stamp is read when the central office equipment receives the second specific position of the second DMT signal. The customer premises equipment adjusts a clock of the customer premises equipment according to the first, second, third and fourth time stamps.

Abstract: Methods, systems, and computer programs for monitoring quality of audio delivered over a communications channel are presented. One method includes an operation for defining timestamps. The timestamps are associated with a measure of time while delivering audio to a client computer, where each timestamp includes a plurality of timestamp bits. Further, the method includes an operation for modulating an audio signal with pseudo noise (PN) codes when a timestamp bit has a first logical value, and modulating the audio signal with a negative of the PN codes when the timestamp bit has a second logical value. After transmitting the modulated audio signal to the client computer, the timestamp bits are extracted from a received modulated audio signal to obtain received timestamps. The quality of the audio is assessed based on the received timestamps, and the quality of the audio is stored in computer memory.

Abstract: A time synchronization method and system for a multi-core system are provided.

Abstract: A frame timing controller includes a timer, a frame timing control unit, and a frame pointer processing circuit. The timer is arranged to generate a timer value according to a first clock signal with a first clock frequency. The frame timing control unit is for triggering at least a receiver to start receiving transmitted information of a base station according to at least a frame pointer and the timer value, wherein the receiver processes an input signal to generate first samples at a first sampling rate corresponding to a sampling clock frequency and processes the first samples to generate an output signal including second samples at a second sampling rate corresponding to a second clock frequency of a second clock signal different from the sampling clock frequency. The frame pointer processing circuit is for generating and updating the frame pointer according to the output signal of the receiver.

Abstract: A technique for cell signature determination in a cellular communication network is described.

Abstract: An apparatus for time synchronization of a femtocell base station receives, via neighboring macrocell base stations adjacent to a femtocell base station, timing packets generated by timing servers directly connected to the neighboring macrocell base stations, and if time synchronization using a GPS satellite is impossible, obtains system time information from a timing packet received via one corresponding to a master base station, among the neighboring macrocell base stations, and performs time synchronization.

Abstract: The present invention provides a method for channel estimation used in a receiver of a multi-carrier communication system, including: receiving a multi-carrier symbols from a transmitter of the multi-carrier communication system; and obtaining channel information of sub-carriers carrying data of the multi-carrier symbols, using selectively time direction interpolation and frequency direction interpolation for channel information of a plurality of scatter pilots of the multi-carrier symbols.

Abstract: Embodiments are directed to timing synchronization between network nodes, such as, for example, based upon IEEE 1588. Example embodiments provide for a node in a IEEE 1588 message exchange to obtain the T3 timestamp without using its host interface to access the physical layer. Methods and systems include aspects of determining an egress timestamp corresponding to a time at which a first packet is transmitted from a physical interface of a first network entity on to a network media, storing the egress timestamp in a memory associated with the physical interface, receiving a second packet at the physical interface, retrieving the egress timestamp from the memory based upon the second packet, and updating the second packet with the retrieved egress timestamp. Embodiments may further include providing the updated second packet for protocol processing in the first network entity, or transmitting the updated second packet from the physical interface on to a network media.

Abstract: A method for time synchronization in a communication network comprising a multiplicity of network nodes, wherein synchronization messages are transmitted in the communication network and the synchronization message received in a slave node contains synchronization information for synchronizing the slave time of the slave node with the master time, i.e., synchronization messages are transmitted in a closed ring or line topology and the slave node receives first and second synchronization messages from different transmission directions, and wherein the slave node synchronizes a first time with the synchronization message from one transmission direction and a second time with the synchronization message from the other transmission direction.

Abstract: A method and receiving device are provided that determine a synchronization byte in a plurality of transport stream packets, wherein the synchronization byte has a predetermined synchronization value. The method/receiving device receives, via a receiver, a portion of a first transport stream packet of the plurality of transport stream packets; detects, starting from the beginning of the portion of a first transport stream packet, a continuous four byte pattern that does not include the predetermined synchronization value; detects a first occurrence of a byte having the predetermined synchronization value; detects a subsequent byte separated from the first occurrence by a predetermined byte length; determines a byte value of the subsequent byte; and validates that the first occurrence is the synchronization byte based on a comparison of the byte value and the predetermined synchronization value.

Abstract: A synchronization processing method for multimedia broadcast multicast service (MBMS), an upper layer network element, and a lower layer network element thereof. The method includes: an upper layer network element sends a synchronization protocol control frame to a lower layer network element, wherein, the synchronization protocol control frame carries the data packet length information of the pre-determined data frame in the synchronization sequence corresponding to the synchronization protocol control frame, and the pre-determined data frame includes at least one of: each data frame, part of a data frame.

Abstract: A communication method using time-division multiplexing that enables permanent communication between user terminals. One of the terminals is a master terminal, the others being slave terminals. The transmission channel is divided into frames, each frame being divided into time slots. Each slave terminal identifies a free time slot in the current frame, in listening mode, and transmits data in the identified time slot, in transmission mode, during at least one following frame. As soon as the slave terminal ceases transmitting, the identified time slot becomes free again.

Abstract: A transparent clock may be provided between edge nodes of a non-precision time protocol network, with an arrival time of a packet at an edge of the non-precision time protocol network carried in a reserved field of a packet.

Abstract: A synchronization method and system of control sequence numbers is provide to achieve radio link control sequence number synchronization between different network elements. This method includes the following steps: allocating a preset radio link control sequence number to a first radio link control protocol data unit corresponding to a first packet in a data burst and successively allocating a radio link control sequence number to subsequent radio link control protocol data units corresponding to packets of this data burst, when each designated network element in a plurality of designated network elements performing radio link control protocol process on the packets in the data burst received by said each designated network element.

Abstract: This invention relates to methods and devices for clock synchronization. The invention makes particular use of IEEE 1588 with offset and skew correction. In embodiments of the invention, the IEEE 1588 Precision Time Protocol is used to exchange time stamps between a time server and a client from which the client can estimate the clock offset and skew. In embodiments of the invention a free running clock at the client is provided with an estimation technique based on the time stamps from the IEEE 1588 PTP message exchange between the server and client clocks. The offset and skew from the estimation process can be combined with the local free running clock to give a synchronized local clock which is an accurate image of the master clock.

Abstract: A method for estimating round-trip time (RTT) values for data packets travelling in a telecommunication network is disclosed. During a first time interval (206) which begins with the start of a data transmission, estimated RTT values (14) are generated by filtering a periodic sequence of RTT samples (12) with a self-initializing expanding memory polynomial (EMP) filter (16) and, after a first switch-over time at the end of the first time interval, the estimated RTT values are generated by filtering the RTT samples with a fading memory polynomial (FMP) filter (18). The first switch-over time is determined by comparing an FMP estimation error and an EMP estimation error, where the FMP estimation error is the difference between an output of the FMP filter and the RTT samples, and the EMP estimation error is the difference between an output of the EMP filter and the RTT samples, and triggering the first switch-over time when the FMP estimation error becomes equal to or less than the EMP estimation error.

Abstract: The present invention is directed a digital data interface device for transferring digital presentation data at a high rate over a communication link. The digital data interface device includes a message interpreter, content module and a control module. The digital data interface device may include an MDDI link controller. The digital data interface device can be used to control a peripheral device, such as a camera, bar code reader, image scanner, audio device or other sensor. In one example, a cellular telephone having a camera with an MDDI link and a digital data device interface is provided.

Abstract: A transmission system which couples a plurality of transmission devices to a control device includes a first transmission device which is one of the plurality of transmission devices; a first calculation circuit which calculates a first difference value indicating a frequency difference value between a common clock supplied from the control device and a first clock as a clock used in the first transmission device; and a transmitter which reports the first difference value to a second transmission device other than the first transmission device, wherein the second transmission device comprises: a second calculation circuit which calculates a second difference value indicating a frequency difference value between the common clock and a second clock used in the second transmission device, and a frequency controller which controls an oscillator generating the second clock so that the second difference value approaches the first difference value reported from the first transmission device.

Abstract: A method and an apparatus for tracking a clock source are disclosed. The method includes determining a best clock source to be tracked by a device according to a best clock source tracked by a slave candidate port in the device and distributing the best clock source tracked by the device through a master candidate port in a master state. Through the embodiments of the present disclosure, the clock source selection of the device converges quickly. Moreover, because the slave candidate port is determined according to the network planning, the planning of the transport network is observed.

Abstract: A device comprises an integrated circuit having first and second domains, the first domain having a first clock boundary module; and the second domain having a second clock boundary module. The first clock boundary module comprises: a buffer, for storing data for transfer to the second domain; and a first controller operable to send a first control signal to the second clock boundary module via a first synchronizer, the first control signal indicating the presence of a packet of data in a first storage location of the buffer. One of the first and second clock boundary modules comprises a multiplexer having an input connected to an output of the buffer and an output connected to circuitry forming part of the second domain.

Abstract: Apparatus and methods for synchronizing a network element (e.g. access points, femtocells, etc.) to a master network (such as a cellular network) to provide accurate frequency and/or time references for their internal systems. In one embodiment, the network element utilizes a dedicated receiver (or transceiver) to receive timing information from the master network. The implementation of the dedicated receiver is advantageous for cost and simplicity reasons. Furthermore, the timing or frequency information, as received from the master network, is used to correct the network element's internal timing. In addition, the network element's internal timing can operate in open-loop mode, if no master network can be found, thereby allowing for the device to continue providing service to network users. Additionally, a dedicated receiver can also receive information (e.g. location, SID, NID, SSID, etc.

Abstract: A wireless communication apparatus operates as a tributary station in a wireless communication system including a control station and the tributary station that perform a time division multiplex communication. The wireless communication apparatus includes a wireless unit that performs a wireless communication with the control station; an event processing unit that notifies of an event occurrence based on an occurrence of an event; and a control unit that controls a communication in synchronization with the control station by detecting a control signal from the control station. When received a notification of the event occurrence, the control unit starts a search operation to acquire the control signal transmitted by the control station. When received the control signal, the control unit transmits a message according to the event occurrence using a slot that has a predetermined position relationship with the slot in which the control signal is received.

Abstract: A communication system and method is provided herein for synchronizing a plurality of network nodes after a network lock condition occurs within a network. According to one embodiment, the method may generate a local trigger signal simultaneously at each of the plurality of network nodes by compensating for unique phase delays attributed to each of the plurality of network nodes. As described herein, the local trigger signals may be used for synchronizing devices, such as multimedia devices, which may be coupled to the network nodes. More specifically, the local trigger signals may be used to synchronize events occurring within devices, which are coupled to different nodes of the network.

Abstract: A timing source is provided for sending timing information via a packet network. The source comprises a first clock for generating the timing information and a packet forming section for forming a sequence of packets. An output section in the form of a packet launch control section transmits the packets via the network as packet bursts, each of which comprises a plurality of packets with the intervals between consecutive packets of each burst being less than the intervals between consecutive packets. A time-stamping section inserts into each packet a transmission time derived from the timing information generated by the clock.

Abstract: A self-stabilizing network in the form of an arbitrary, non-partitioned digraph includes K nodes having a synchronizer executing a protocol. K?1 monitors of each node may receive a Sync message transmitted from a directly connected node. When the Sync message is received, the logical clock value for the receiving node is set to between 0 and a communication latency value (?) if the clock value is less than a minimum event-response delay (D). A new Sync message is also transmitted to any directly connected nodes if the clock value is greater than or equal to both D and a graph threshold (TS). When the Sync message is not received the synchronizer increments the clock value if the clock value is less than a resynchronization period (P), and resets the clock value and transmits a new Sync message to all directly connected nodes when the clock value equals or exceeds P.

Abstract: A method and system for synchronizing data between a mobile terminal and an Internet phone is provided. The method includes transmitting an Internet Protocol (IP) address request message from a mobile terminal to an Internet phone, transmitting an IP address response message from the Internet phone to the mobile terminal in response to the IP address request message, establishing a connection between the mobile terminal and the Internet phone using the IP address, and performing data synchronization between the mobile terminal and the Internet phone through the connection.

Abstract: A device for controlling frequency synchronization includes a processor for controlling a phase-controlled clock signal to achieve phase-locking with a reference clock signal, and for controlling a frequency-controlled clock signal so as to achieve frequency-locking with the reference clock signal. The processor is also configured to monitor a deviation between the frequency and phase-controlled clock signals, detect a change of circumstances such as temperature changes causing frequency drifting of the frequency-controlled clock signal, and replace or correct the frequency-controlled clock signal with, or on the basis of, the phase-controlled clock signal when both the monitored deviation and the detected change of circumstances show correlation confirming frequency drift of the frequency-controlled clock signal.

Abstract: Methods and apparatus that may be used to provide timestamps to physical layer devices are provided. One method includes obtaining a time value from a clock associated with a physical layer device that is communicatively coupled to a primary data packet switch. The method further includes adding a processing time to the time value to generate a timestamp and transmitting the timestamp to a multiplexer circuit. The method further includes writing the timestamp in parallel from the multiplexer circuit to a plurality of external physical layer devices that are communicatively coupled to a secondary data packet switch and are located external to a housing of the secondary data packet switch.

Abstract: A two-step uplink synchronization method is provided for uplink synchronization between a mobile station and a pico/femto base station that is deployed together with an overlay macro/micro base station. In a first step, the pico/femto BS encodes and broadcasts UL transmission timing advance offset information via a broadcast channel. The MS decodes the received UL transmission timing advance offset information and advances its uplink timing for uplink ranging or reference signal transmission based on the decoded offset value. In a second step, the MS and the pico/femto BS performs regular uplink synchronization and uplink access. In one example, the UL transmission timing advance offset information indicates a round-trip propagation time of radio signals between the pico/femto base station and the overlay macro/micro base station. By using the two-step uplink synchronization method, a unified synchronous ranging channel may be used for ranging and UL access in pico/femtocells with reduced interference.

Abstract: A method of synchronizing an equipment unit (200) connected to a communications network (110), the equipment unit being connected to an electrical power supply network (120) providing at least one alternating current power supply voltage (121), the method including the steps of measuring a time difference between the power supply voltage and a synchronization voltage (131), computing a synchronization value, communicating the synchronization value to the equipment unit, the equipment unit detecting the power supply voltage passing through the given state, and synchronizing the equipment unit substantially simultaneously with detecting the supply voltage passing through the given state from the synchronization value. The invention also relates to a synchronization device (300) and a synchronization module (400) used in the synchronization method.

Abstract: A method for indicating one-way latency in a data network, with continuous clock synchronization, between first and second node having clocks that are not synchronized with each other includes a continuous synchronisation session and a measurement session. The method repetitively sends predetermined synchronization messages from the first node to the second node and from the second node to the first node, calculates a round trip time for each message at the first node, updates a synchronization point if the calculated round trip time is smaller than a previously calculated round trip time, stores the updated synchronization points of a synchronization window, and calculates a virtual clock from the updated synchronization points of the synchronization window. The measurement session collects multiple measurements of one-way latency between the first and second nodes using the virtual clock, and generates a latency profile by interpolating the multiple measurements.

Abstract: A method of routing synchronization messages in a packet communication network, in which a packet is routed using a global routing table. A piece of equipment in the network implements the following steps: detecting a packet carrying a synchronization message in a packet stream; determining an output port; emitting a packet carrying the message at the determined output port, the message being modified using a piece of information representing a time of transit in the equipment. A synchronization routing table, which stores at least one association between an input port and at least one output port, is configured in the equipment. When the packet carrying the received message indicates a routing needs to be carried out using the synchronization table, the output port for this packet is determined by the equipment according to an input port on which the packet is received and by reading the synchronization table.

Abstract: There is provided an optical transmission device which includes a determiner, a convertor, and a switch. The determiner determines whether a frame includes a fixed stuff byte area or not when the frame is received from a first network, where the frame includes a payload area for storing client data and the fixed stuff byte area is for storing fixed data. When the determiner determines that the frame includes the fixed stuff byte area, a convertor to convert a fixed stuff byte area into the payload area and a switch switches a clock frequency from a first clock frequency used in the first network to a second clock frequency used in a second network when the frame including the converted fixed stuff byte area is output to the second network on the basis of the clock frequency as a reference.

Abstract: In a communication system wherein a plurality of electronic devices connect and disconnect from communication over a medium and wherein the communication system has a protocol such that it is followed by the plurality of electronic devices when using the communication system, a probing device attempts to detect presence of a listening device and parameters associated with a connection to be set up between the probing device and the listening device by sending a probe request packet directed to the listening device and sending, from the listening device, a probe response packet in response to the probe request packet, wherein the listening device bypasses at least one step of the protocol when sending the probe response packet.

Abstract: In an embodiment, a location, a type of application, and a probability of transition to a no-coverage area are determined for each of a plurality of wireless devices in communication with an access node, and a collaborative group of wireless devices which have requested a data stream are selected. A first portion of the data stream is sent to each wireless device to synchronize the requested data stream, and at least one additional portion of the data stream is sent to each wireless device, where a number of the at least one additional portions sent to each wireless device is based on a modulation and coding scheme assigned to each wireless device. A mapping table is broadcast to the collaborative group, and the wireless devices exchange the additional portions of the data stream according to the mapping table when the collaborative group transitions to the no-coverage area.

Abstract: An output signal adjustment system includes a signal adjustment unit, a reference slope generating unit, a slope detecting unit, a voltage-to-current conversion unit, and a control unit. The slope detecting unit compares the slope of the rising and falling edges of the output signal of the reference slope generating unit with that of the signal adjustment unit and outputs a voltage signal. The voltage-to-current conversion unit converts the voltage signal into a current signal. Based on the current signal, the control unit outputs a control signal for controlling the adjustment of the signal adjustment unit to the slope of the rising and falling edges of the output signal. The output signal adjustment system can automatically adjust the slope of the rising and falling edges of the output signal, so that the output signal is insensitive to the packaging, the printed circuit board, the transmission line and other sender loads.

Abstract: Embodiments are directed towards resynchronizing the processing of a monitored flow based on hole detection. A network monitoring device (NMD) may be employed to passively monitor flows of packets for a session between endpoints. The NMD may receive copies of the monitored flow and perform processes on the monitored flow. In some situations, some copies of packets may not be fully processed by the NMD, creating a hole in the processing. If a hole is detected in the monitored flow and the processing of the monitored flow is desynchronized, then the NMD may suspend processing until it is resynchronized or for a remainder of the session. If the processing is desynchronized, then the NMD may resynchronize the processing by resuming the processing of the monitored flow at a downstream position of the monitored flow based on the detected hole.

Abstract: Device and methods determine timing parameters and associated timing actions from timing messages in communication packets. The timing messages may be encapsulated with a plurality of communication protocols. An example timing message may be an IEEE 1588 timing message encapsulated in an Internet protocol packet encapsulated in an Ethernet protocol packet. The protocols are matched in classifier blocks by comparing portions of the packet to bit values or ranges of values. Operation of other than the first classifier block depends on results of matching in the preceding block by using offset values passed between blocks that indicate starting points for the matching. The final classifier block matches values in timing messages to identify timing parameters and associated timing actions in the message.

Abstract: A method of communicating count value information in an Optical Transport Network (OTN) signal frame. The method comprises determining a count value indicating a number of payload bytes to be sent in a next OTN signal frame; determining that a change in the count value (?) with respect to a current count value is within a predetermined range; selecting an inversion pattern indicating the change in the count value; determining a cyclic redundancy check (CRC) code associated with the inversion pattern; and, inserting the inversion pattern and the CRC code in a Generic Mapping Procedure (GMP) overhead of the OTN signal frame.

Abstract: A Managed Timing Engine (MTE) provides a primary timing output synchronized to a selected input reference from a multiplicity of input references. Additional timing outputs can be generated such that there is a programmable frequency offset (in ppb) between them and the main output. The rate (in Hz) of the outputs can be programmable. The MTE can introduce a programmable delay for periodic phase references.

Abstract: A method of measuring temporal drift of an electronic apparatus linked to a network and capable of providing a time-stamp including capturing at least two messages including a gauge reference time circulating around the network, and determining precision of the time-stamping function of the apparatus as a function of the gauge reference time and of a time-stamp provided by the apparatus. The apparatus can be a network analyzer and each message captured includes at least one Ethernet frame including a gauge reference time in accordance with NTP (Network Time Protocol).

Abstract: Various embodiments of primary synchronization signal detection are provided. In one aspect, a method receives one or more signals at one or more antennas of a receiver. The method processes the one or more received signals by decimation filtering the one or more received signals to provide one or more decimated signals, each of the one or more decimated signals having a predetermined symbol size, and enumerating correlation of the one or more decimated signals with a plurality of reference signals to provide correlation results. The method then detects a primary synchronization signal (PSS) based on the correlation results.

Abstract: A programmable device generates a test signal indicative of a RF signal and receives a processed test signal indicative of the test signal after processing thereof by one of a RF transmission system and a RF receiving system. The programmable device performs a comparison between the processed test signal and calibration data, and generates a report based on the comparison. A hardwire signal router provides the test signal to one of the RF transmission system and the RF receiving system, and provides the processed test signal to the programmable device. The router includes a first switching mechanism and a second switching mechanism operating in a coordinated fashion to define one of a first state for testing the RF transmission system and a second state for testing the RF receiving system.

Abstract: Systems and methods and systems are disclosed for allowing the medium access control (MAC) layer in a communication system within an integrated circuit or device to accurately determine a timestamp point and a timestamp value when, for example, the Precision Time Protocol (PTP) protocol is in use by the communication system. Such determination of accurate timestamp point and timestamp value may be used by the communication system to account for and to compensate for the time shift(s) from forward error correction (FEC) sublayer changes in a data frame that is transmitted by the MAC layer. Feedback is provided to the MAC from the FEC to allow the MAC to accurately determine the timestamp point and timestamp value align preamble of the data frame to the beginning of the FEC bit block that is output by the FEC sublayer.

Abstract: A fault tolerant video streaming distribution service utilizes multiple distribution servers to receive and process a video stream simultaneously. Each distribution server performs a mapping of each encoded timestamp associated with a transport stream having time discontinuities to a continuous time sequence. The distribution servers coordinate the timestamp mapping through a distributed leader election protocol that elects a leader to coordinate the timestamp mapping in an environment where failures are anticipated and the number of distribution servers dynamically changes without notice.