Abstract: Wireless client devices within a wireless network exchange data with other wireless devices during particular time slots determined by the network. More particularly, the system generates and wirelessly broadcasts synchronization information to the client devices, where the synchronization information contains individual masks to be applied to bit fields of individual client devices, where said time slots are determined in accordance with the masked bit fields. In such a manner, client devices can be coordinated to communicate with the system in a dynamic real-time tiered manner.

Abstract: Systems and methods enable adaptive, single bit-timeslot granular digital multiplexing capable of automatically and dynamically selecting an appropriate input bit from a set of alternative input ports, based on a current status of the alternative inputs. The invention enables input-status-adaptive, dynamic multiplexing of individual bits from multiple, e.g. byte-wide, input ports onto, e.g. a byte-wide, multiplexer output. An input status adaptive, dynamic, bit-granular M-by-M digital cross-connect can be formed out of an arrangement of M (an integer) instances of the input-controllable adaptive M:1 multiplexers. An application is a synchronous, digital network channel that can be dynamically shared, even at a single bit time-slot granularity, among multiple path sources, which furthermore can be located even at different network nodes.

Abstract: A computer node comprising a synchronization unit for comparing network timing information for a first network with network timing information for a second network and for communicating to the first network the sign of the difference between the first network timing information and the second network timing information to allow the first network to alter its network timing information using the sign of the difference to allow the network timing difference between the first network and the second network to be reduced.

Abstract: A disclosed network device includes a plurality of interface cards that receive clock signals and clock signal quality information from other devices via communication lines, respectively being predetermined communication line types corresponding to the plurality of interface cards, a controller that acquires the clock signal quality information and determines one of the clock signals having a highest quality based on this, and a clock processor that generates a synchronization clock signal used for network synchronization the clock processor, based on the determined one of the clock signals, whereby the clock processor includes a frequency measuring instrument that measures a frequency component of the one of the clock signals, and determines the communication line type corresponding to one of the interface cards, and a clock controller that provides a coefficient to a digital filter based on the determined communication line type.

Abstract: The invention discloses a sink device and a signal receiving method thereof, applicable to wireless local area network. The sink device receives a plurality of beacon signals, synchronizes the beacon output signal generated by itself with the operating clock of the source device according to the above-mentioned timing synchronization data. And the sink device receives the plurality of beacon signals according to this calibrated synchronization clock.

Abstract: An input bit stream including a clock signal and data bits is oversampled to obtain one or more sets of data samples. One or more sets of non-transitioning phases corresponding to data samples that do not switch between zero and one are then identified. Center phases corresponding to the one or more sets of non-transitioning phases are identified and then a final center phase that accurately represents the bits belonging to the input bit stream is selected. The data samples corresponding to the final center phase are extracted, thereby recovering the clock signal and data bits from the input bit stream.

Abstract: Apparatus, systems, and methods are provided for transmitting messages over a serial interface. A method comprises receiving a first signal at a first time and receiving a second signal at a second time, the second time being after the first time. If a difference between the second time and the first time is less than a threshold time period, the method comprises generating a first message that is representative of the first signal and the second signal and transmitting the first message over the serial interface. In accordance with one embodiment, the threshold time period is equal to one half of an interface acquisition delay time period associated with the serial interface.

Abstract: The present invention relates to an apparatus and method for estimating and compensating for a time offset and a carrier frequency offset in a Multiple Input Multiple Output (MIMO) communication system that supports Orthogonal Frequency Division Multiplexing (OFDM) or Orthogonal Frequency Division Multiplexing Access (OFDMA). According to the present invention, a phase difference of pilot signals of the same transmitting antenna, which are received through receiving antennas, is calculated. An arc tangent operation is then carried out on the phase difference of the pilot signals to calculate a time offset linear phase and/or a carrier frequency offset linear phase. Further, a time offset compensation value and/or a carrier frequency offset compensation value are found by employing the time offset linear phase and/or the carrier frequency offset linear phase.

Abstract: The present invention relates to an apparatus and a method for receiving signal for extent of timing synchronization in MB-OFDM UWB System. The invention divides the digital samples completed of sampling twice as much as minimum sampling clock required to restore the MB-OFDM received signal into ODD data path and EVEN data path, executes the packet detection and timing synchronization for each of divided path and selects the data of path with larger cross correlation value at the timing synchronization point to secure the stable receiving performance in system environment with severe frequency offset and prevent the FTT window shift within preamble section through adding minimum hardware and structural change without increasing the system clock.

Abstract: A system including a magnitude measuring module, an energy normalization module, and a metric generation module. The magnitude measuring module is configured to measure magnitudes of real portions of differentially demodulated signals, wherein the differentially demodulated signals are generated by differential demodulation of signals received from a base station. The energy normalization module is configured to generate a sum of energies of a plurality of subcarriers included in the signals received from the base station. The metric generation module is configured to generate a plurality of metrics for a plurality of symbols included in the signals received from the base station. The metric generation module is further configured to detect, based on the plurality of metrics, a preamble symbol included in the signals received from the base station.

Abstract: A bus system for the real-time communication of a superordinate unit with one or more subordinate units is used for exchanging address and data information via a bus. For the rapid exchange of messages, further fields are provided between the fields for the address and data information.

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.

Abstract: A radio base-station apparatus with improved frame transmission efficiency by avoiding interference of preambles and frame control information between sectors of a cell or between cells with a frequency reuse factor. In the apparatus OFDMA multiple-access processing is performed for each of a plurality of sectors of a cell, and frames made of logical subchannel numbers and OFDMA symbol numbers are configured in synchronization respectively for the plurality of sectors, and offsets are added to the beginnings of given frames such that the preambles and frame control information arranged sequentially from the beginnings of the frames do not overlap on the OFDMA symbol numbers.

Abstract: Provided is a base station capable of performing cell search of all mobile stations having different communicable frequency band widths in a scalable band width communication system to which a multi-carrier communication method such as the OFDM method is applied. The base station includes: a modulation unit (102) for modulating SCH data after being encoded; a sub carrier setting unit (105) for setting one of the sub carriers to a sub carrier (SCH sub carrier) constituting the OFDM symbol for SCH data transmission; and an IFFT unit (106) for mapping the SCH data to the sub carrier set by the sub carrier setting unit (105) among the sub carriers and performing IFFT to generate an OFDM symbol. The sub carrier setting unit (105) sets one of the sub carriers which has a frequency of a common multiple between the sub carrier interval and the cell search interval as an SCH sub carrier.

Abstract: The invention concerns a method for receiving a multi-carrier signal of reduced complexity when the number of carriers is not high. The method includes: demodulating the multi-carrier signal; converting a received signal received in binary representation into a modal representation in a base of at least two mutually prime numbers on a finite space of size equal to the product of the mutually prime numbers; demodulating including conversion.

Abstract: A technique for maintaining time synchronization between network nodes involves broadcasting a timing signal from a source node to its neighbors. The timing signal is transmitted in a dedicated source time slot of a super epoch comprising a number of epochs each having a number of time slots. A reply timing signal is received at the source node from a neighboring node designated as the destination node, where the reply timing signal is received in a dedicated destination time slot of the super epoch. The clock drift and propagation delay between the source and destination nodes are computed at the source node. At the neighboring nodes other than the destination node, clock drift can be computed using previous estimates of propagation delay. RTS and CTS exchanges from PTP packets can also be used to estimate the propagation delay in the source node and the clock drift in the destination node.

Abstract: The present invention is an improved system and method for detecting the leading edge of a waveform. More specifically, the invention relates to detecting the leading edge of an ultra wideband waveform. The invention requires locking to the ultra wideband waveform at a lock reference time, and sampling the ultra wideband waveform during one or more time windows relative to the lock reference time to identify one or more leading edge candidate times based on one or more detection criterion. The ultra wideband signal is sampled at a band limited Nyquist rate that avoids aliasing within a band of interest of the ultra wideband waveform, but allows aliasing outside of the band of interest to minimize the number of samples for leading edge detection processing.

Abstract: A method and a circuit for obtaining asynchronous demapping clock. The method includes: obtaining a smoothed clock with even gaps in accordance with data to be demapped and a corresponding clock signal; performing phase locking in accordance with a signal reflecting writing and reading conditions of data of a First In First Out (FIFO), to obtain a clock signal required for demapping. The method can effectively filter off jittering created during asynchronous mapping/demapping processes and may ensure a high-performance clock output. Furthermore, the method is applicable to not only mapping from OTN to SDH but also other asynchronous demapping processes, e.g., mapping from SDH to OTN, and thereby effectively improving the performance of data demapping.

Abstract: A technique for encoding digital communication signals. Data symbols are augmented in pilot symbols inserted at predetermined positions. The pilot augmented sequence is then fed to a deterministic error correction block encoder, such as a turbo product coder, to output a coded sequence. The symbols in the error correction encoded sequence are then rearranged to ensure that the output symbols derived from input pilot symbols are located at regular, predetermined positions. As a result, channel encoding schemes can more easily be used which benefits from power of two length block sizes.

Abstract: A method of processing data comprises the receiving a frame of data having a predetermined number of time slots (502,504,506). Each time slot comprises a respective plurality of data symbols (520). The method further comprises a primary (508), a secondary (510) and a tertiary (512) synchronization code in each said predetermined number of time slots.

Abstract: A system and method that facilitates multiple systems of communicating devices, i.e., a master device and one or more implantable slave devices, to coexist on a common, e.g., RF, communication channel having a limited temporal bandwidth while maintaining the required update rate between each master device and its associated slave devices. In embodiments of the present invention, master devices periodically transmit one or more beacon messages that are suitable for identification by other such master devices at a communication range greater than the communication range that may cause interference between systems and thus enabling one or more systems to cause the position of its frame periods to be interleaved with the frame periods of other such systems in anticipation of systems moving in closer proximity and actually interfering with each other.

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.

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.

Abstract: A receiver in an impulse wireless communication. The receiver (300) includes a pulse-pair correlator (304) that receives a signal (316) and divides it into two signals for paths. One of the signals is input to signal multiplier (312) while another signal is delayed by a delay unit (310). The signal multiplier (312) multiplies the received signal (316) by a delayed signal (318). An integrator (314) integrates an output signal (322) over a designated period of time. An adding module (306) sums an output signal (324) from the integrator (314). An acquiring module (308) compares an summing-up output (326) from the adding module (306) with a predetermined threshold value to detect the existence of a transmitting-standard preamble.

Abstract: A system includes an input, a differential demodulation module, a magnitude measuring module, a summing module, and a metric generator module. The input receives input signals that include s sets of modulated sub-carriers carrying symbols, where s is an integer greater than or equal to 1. The differential demodulation module generates differentially demodulated signals based on the input signals. The magnitude measuring module measures magnitudes of real portions of the differentially demodulated signals. The summing module generates s sums, wherein each of the s sums is a sum of the magnitudes generated based on a respective one of the s sets. The metric generator module generates metrics for the symbols based on the s sums.

Abstract: A method for detecting a specific timing from a synchronization channel is described. A signal with a known sequence is received. Two or more correlation values between the received signal and the known sequence are calculated at two or more positions. The two or more correlation values are compared. A determination is made whether the position of the known sequence has been shifted based on the comparison. A specific timing of a synchronization channel is detected based on the determination.

Abstract: The invention relates to a communication system and a method for controlling a communication system for communicating audio data between each of a plurality of terminal units (T1-T3). In order to provide a deterministic communication protocol with lowest possible overhead and a system for implementing same said method is characterized by the steps of: examining an identity of said terminal units (T1-T3) by said central unit (10) during an initialization phase; transmitting a predetermined data frame including a first synchronization signal, a terminal unit address of a respective terminal unit, a payload field and a second synchronization signal by said central unit (10) via said master bus (14) during a configuration phase; and transmitting audio data through said data bus (12) by one of said plurality of terminal units (T1-T3) within an audio sample time interval that corresponds to the interval between said first synchronization signal and said second synchronization signal.

Abstract: In a cellular system in which OFDM is used, a forward link synchronization channel, a common pilot channel structure, an initial cell searching method of a mobile station, and an adjacent cell searching method for handover are required. A method of transmitting a forward synchronization signal in a wireless communication system according to the present invention includes generating a frame comprised of a plurality of sync blocks; and transmitting the frame through a forward link, wherein the frame comprises primary synchronization channel sequences which provide timing information of the sync blocks and a plurality of secondary synchronization channel sequences which provide timing information of the frame, wherein a cell identifier is specified by a combination of the primary synchronization channel sequence and a hopping code word specified by the plurality of the secondary synchronization channel sequences. Therefore, the cell searching time can be efficiently reduced in an OFDM system.

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.

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.

Abstract: A wireless local area network (WLAN) transceiving integrated circuit services voice communications in a WLAN with at least one other WLAN device. The WLAN transceiving integrated circuit includes a WLAN interface, an input buffer, a transcoder, and a processor. The WLAN interface wirelessly communicates with the at least one WLAN device to receive packetized audio data from the at least one WLAN device. The input buffer operably couples to the WLAN interface and receives the packetized audio data from the WLAN interface. The transcoder converts the packetized audio data to Pulse Code Modulated (PCM) audio data and outputs the PCM audio data to a coupled audio COder/DECoder (CODEC) such that the PCM audio data is substantially temporally aligned with Radio Frequency (RF) slots of the WLAN interface.

Abstract: To remove DC offset from received data symbols having cyclic prefixes in a data communication system, means (5) are provided for determining the location of the cyclic prefixes, means (3) are provided for calculating the DC offset by calculating a mean value of at least one data symbol without its cyclic prefix and means (4) are provided for subtracting the calculated DC offset from said at least one data symbol with its cyclic prefix.

Abstract: A method of generating a code sequence and method of adding additional information using the same are disclosed, by which a code sequence usable for a channel for synchronization is generated and by which a synchronization channel is established using the generated sequence. The present invention, in which the additional information is added to a cell common sequence for time synchronization and frequency synchronization, includes the steps of generating the sequence repeated in time domain as many as a specific count, masking the sequence using a code corresponding to the additional information to be added, and transmitting a signal including the masked sequence to a receiving end.

Abstract: A method to enable scheduling communications activities for an electronic communication device configured to communicate across a communication network is provided. The method comprises the steps of scheduling a communication activity during a scheduling window such that the communication activity is scheduled to occur toward the end of a communication window; entering a power-save mode after the scheduling step; and transitioning from the power-save mode prior to the scheduled communication activity. In one embodiment the method can further include a step of conducting the scheduled communication activity and transitioning back to the power-save mode after a next communication activity is scheduled or be implemented to allow the step of conducting the scheduled communication activity and transitioning back to the power-save mode at the end of the next communication window.

Abstract: A pilot structure, a method, and a receiver for multi-carrier cellular communications communication system include a network element and a user equipment. The network element is configured to transmit a pilot sequence. The user equipment is configured to detect a pilot sequence comprising a primary synchronization sequence at predetermined number of sub-frames at a center of a bandwidth, a primary common pilot for each sub-frame, and short system information once per frame at the center of the bandwidth, and to decode the short system information to identify system frame timing and a system bandwidth of a cell.

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.

Abstract: A clocking circuit of a receiving unit performs a clocking operation synchronously with a network clock. A packet output circuit of the receiving unit outputs a second packet included in a first packet and outputs a control signal indicating normality/abnormality of output timing of the second packet based on a result of comparing a time of the clocking circuit and a time of first time information included in the first packet. A clock adjusting circuit of a processing unit synchronizes, when the second packet includes second time information indicating a time based on a transmitting side reference clock and when the control signal indicates normality, a receiving side reference clock with the transmitting side reference clock based on a result of comparing a time based on the receiving side reference clock and a time of the second time information.

Abstract: A method and apparatus to perform buffer management for media processing are described.

Abstract: A method of processing data comprises the receiving a frame of data having a predetermined number of time slots (502,504,506). Each time slot comprises a respective plurality of data symbols (520). The method further comprises a primary (508), a secondary (510) and a tertiary (512) synchronization code in each said predetermined number of time slots.

Abstract: In a mobile communication system, multiple transceivers perform radio communications in the same frequency band.

Abstract: When packets reach from the 0 system and the 1 system, the packet selecting means 21 determines, based on the sequence numbers held in the packet output record register 22, whether or not the corresponding packet has passed, interrupts passing of the corresponding packet to the output side if passed, and allows the corresponding packet to pass to the output side if not passed. When the packet selecting means 21 selects a packet and allows the packet to pass to the output side, the packet output record register 22 holds the sequence number of the corresponding packet as a packet output record. Phase adjusting means that absorbs an average difference in delay for transmission between the systems may be provided at a stage before the packet selecting means 21.

Abstract: An embodiment of an interface system including, among others, an aggregation device comprising a plurality of ports, a first device comprising a plurality of ports, and one or more links that link the entire plurality of ports of the aggregation device and first device, the one or more links fewer in quantity than the entire plurality of ports.

Abstract: Receivers (1) for receiving frequency signals are, to improve their time synchronization accuracy, provided with synchronization stages (20) for performing a coarse time synchronization through autocorrelating samples of a group of preamble symbols (t1,t2,t3) and a fine time synchronization through crosscorrelating samples of a further group of preamble symbols (t10,G1) with predefined samples. The synchronization stages (20) also perform a coarse and a fine frequency synchronization through detecting and accumulating phases of samples of a yet further group of preamble symbols (t8,t9) and of another group of preamble symbols (T1,T2). The synchronization stages (20) have buffering units (21) and controlling units (22) for controlling mixing units (11) and transformating units (12) in processing stages (10). The preamble symbols have ten short preamble symbols (t1-t10), a guard interval preamble symbol (G 1) and two training symbols (T 1,T2).

Abstract: Disclosed are a method of and system for enabling the transport of timer protocols over a generic frame procedure (GFP) network. The method comprises the steps of transmitting a defined optical initialization sequence to a GFP mapper, and using that GFP mapper to detect the optical initialization sequence and to generate a specified GFP frame to represent the initialization sequence. This specified GFP frame is recognized as a control frame for timer initialization. In a preferred embodiment, the timer protocol uses biphase encoding to encode clock data, and the method comprises the further steps of recovering clock data from a data stream that uses the biphase encoding, detecting a clock rate in that data stream, and using a look up table to map said detected clock rate into a specific code for said control frame.

Abstract: A method of data transmission in a data communication network includes negotiating a connection between a source terminal and a destination terminal in the data communication network. During the connection negotiation process, optimal field lengths are determined for recording a source identifier and a sequence number in data packets transmitted in the connection. The source identifier identifies a connection from the source end to the destination end of the data transmission, while the sequence number identifies the relative position of a data packet in a series of data packets transmitted in the connection. The length of the source identifier and sequence number fields may either be calculated or selected from a set of predetermined field length values.

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.

Abstract: A composite signal includes a high power beacon signal and low power corresponding wideband synchronization signal and is communicated over a time interval exceeding a single OFDM transmission time interval. A base station transmits one or more different such composite broadcast signals in a recurring timing structure. Each different potential beacon signal, e.g., a single tone signal, is paired with a unique wideband synchronization signal. A wideband synchronization signal includes at least some predetermined null tones and at least some predetermined non-null tones. For a given wideband synchronization signal, the predetermined null tones carry predetermined modulation symbol values, A wireless terminal receives a composite signal, identifies a beacon, determines a corresponding known wideband synchronization signal, compares received to known wideband synchronization signals, and determines at least one of a timing adjustment, frequency adjustment and channel estimation.

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.

Abstract: The present invention is directed to a system and method for channel estimation for a communication channel such as, for example, that found in a wireless communication network. One or more synchronization and channel estimate symbols can be combined to compute a refined channel estimate.

Abstract: A data transmission process with auto-synchronised correcting code, auto-synchronised coder and decoder, corresponding transmitter and receiver. According to the invention, synchronisation management signals (HS, SS, ID) are formed and, under the control of these signals, a header is inserted before a data group and after it a correcting code. At receive end, these synchronisation management signals are reconstituted, the presence of a header is detected and any erroneous symbols are corrected. The invention also provides for an auto-synchronised coder and a decoder and for a transmitter and a receiver using them.