A network device includes control logic coupled to a receiver. The control logic detects an synchronization packet received via the receiver from a second network device over a network that is precision time protocol unaware. The control logic determines that a portion of the synchronization packet is asserted, indicating that the synchronization packet has incurred congestion traversing the network. The control logic adjusts, based on an assertion of the portion, a weight applied to timestamps associated with sending and receiving the synchronization packet in performing clock synchronization with the second network device.

Processing a digital bit stream and systems for implementing the methods are provided. The method includes dividing the digital bit stream into a plurality of data packets. In a first processing block performing a carrier recovery error calculation on a first portion of the plurality of data packets, comprising preforming a first phase locked loop (PLL) function on decimated data of the data packets and performing a carrier recovery operation on the first portion of the plurality of data packets. In a second processing block, in parallel with the processing of the first portion of the plurality of packets, performing the carrier recovery error calculation on a second portion of the plurality of data packets, comprising preforming the first PLL function on decimated data of the data packets and performing the carrier recovery operation on second portion of the plurality of data packets.

A system includes a plurality of line cards and a timing card. A clock generation circuit on the timing card generates a clock signal which is pulse width modulated according to information to be transmitted. A clock line supplies the pulse width modulated clock signal to the line cards. The timing card sends a first control word to the plurality of line cards over the clock line after sending a beacon. The first control word includes a size field specifying a first length of first data following the first control word. The timing card sends time of day information over the clock line to the line cards following the first control word. The time of day information may be encrypted. A second control word follows the time of day information. One or more additional control words can follow the second control word before the next beacon.

An apparatus for communication between a sending application and a receiving application of a receiving apparatus includes a processor that is configured to establish a stream for transmitting data between the sending application and the receiving application; receive a first request from the sending application to transmit metadata to the receiving application; receive a second request from the sending application to transmit application data to the receiving application; responsive to a determination that a frame that includes the application data and the metadata has a size that is smaller than or equal to a maximum frame size, construct the frame to include the application data and the metadata; and transmit the frame in a packet to the receiving apparatus.

A method and apparatus according to the present invention addresses and/or prevents lost protocol synchronization in HARQ systems caused by ACK/NACK errors. One embodiment detects lost synchronization errors for NDI-based retransmission protocols and restores synchronization by sending an explicit RESET message. In response to the RESET message, the transmitter aborts the transmission of a current PDU and transmits a new PDU and corresponding NDI. Another embodiment prevents protocol synchronization errors by sending scheduling grants on a packet by packet basis. The receiver sends a subsequent explicit scheduling grant to the transmitter based on an error evaluation of a received PDU. The transmitter will not send the next PDU unless it receives the subsequent explicit scheduling grant.

Systems and methods for extracting and identifying timing information from wireless signals can include a signal receiver configured to receive a communications signal; a finite impulse response (FIR) filter coupled to the signal receiver and configured to identify a set of transitions in the communications signal; an absolute value operation module coupled to the FIR filter and configured to detect energy in each of the set of transitions within the communications signal; and a comb filter coupled to the absolute value operation module and configured to combine the detected energy in each of the set of transitions within the communications signal. Exemplary systems can also include a cyclic accumulator coupled to the comb filter and a signal processor.

A sensor includes detection circuitry and control circuitry coupled to the detection circuitry. The detection circuitry generates a detection signal indicative of a detected physical quantity. The control circuitry, in operation receives the detection signal and a frequency-indication signal, and generates a trigger signal based on the frequency-indication signal and a set of local reference signals. The sensor generates a digital output signal and a locking signal based on the trigger signal and the detection signal. The generating the digital output signal includes outputting a sample of the digital output signal based on the trigger signal. The locking signal is temporally aligned with the digital output signal.

Fast sampling phase and frequency acquisition suitable for incorporation into various high bandwidth receivers and receiving methods. One illustrative integrated circuit receiver or deserializer design has: a clock circuit that provides a sample clock; an analog to digital converter that samples a receive signal in accordance with the sample clock to provide receive signal samples; and a clock recovery circuit. The clock recovery circuit includes: a phase and frequency acquisition module to determine and correct an initial frequency offset and an initial phase offset of the sample clock; and a feedback circuit to minimize timing error of the sample clock after the initial frequency offset and initial phase offset have been corrected.

The present invention is directed to data communication. More specifically, embodiments of the present invention provide a transceiver that processes an incoming data stream and generates a recovered clock signal based on the incoming data stream. The transceiver includes a voltage gain amplifier that also performs equalization and provides a driving signal to track and hold circuits that hold the incoming data stream, which is stored by shift and holder buffer circuits. Analog to digital conversion is then performed on the buffer data by a plurality of ADC circuits. Various DSP functions are then performed over the converted data. The converted data are then encoded and transmitted in a PAM format. There are other embodiments as well.

The present embodiment relates to, for example, a transceiver system capable of notifying a transmission device of an asynchronous state of a reception device with a simple configuration. The reception device includes an input unit, a synchronous-state detector, a resistance-value controller, and a terminal resistor. When the synchronous-state detector detects the asynchronous state, the resistance-value controller sets a resistance value of the terminal resistor to a resistance value indicating the asynchronous state. The transmission device includes an output unit, an amplitude detector, an output controller, and a transmission resistor. The output controller causes the output unit to output a signal constituting normal data including clock information when the synchronous state of the reception device is detected, and causes the output unit to output a signal constituting training data including the clock information when the asynchronous state of the reception device is detected.