A process of scheduling stream packets for output from a multiplexing network device involves prioritizing the output of packets first according to stream priority, and within a particular priority, by stream ID.

Disclosed are methods and apparatus to utilize virtual timing markers to improve transmission and reception of electronic or optic signals having timing markers such as zero-to-one transitions. Physical timing markers are augmented or substituted with relocatable messages containing displacements or time offsets to other physical timing markers in a reference signal waveform. Additionally disclosed are virtual timing marker methods to improve transmission performance, qualities, operation, or use, such as timing markers that can overlap other timing markers or other signal content waveforms, seamlessly span over intermittent signals, or reference the more precise underlying signal carrier waveforms as well as timing marker error detection and correction, dispersed redundant timing markers, statistical precision enhancement, concealing timing markers from jammers, subscriber access by encryption, increased signal content efficiency, and reduced multiplexing. These are beneficial in handling and relaying high precision positioning-navigation-and-timing signals, or for piggybacking them on other purpose signals.

A system and a method for time synchronization on a wireless network, based on the exchange of Chirp Spread Spectrum information. Time signals are broadcast from a master (40) to a plurality of slave devices (101, 102, 103). The modulation used includes a compensation of offsets in the master's system clock by symbol-wide frequency shifts that is particularly precise, fine and simple to implement. The system and method of the invention are particularly suitable for synchronizing a telecommunication cell network.

A system for optimizing short-term stability of a clock source clock pulse synchronized with a long-term stable reference-clock transmits clock numbers of a first reference clock to the clock source, between an initialization time and several times within a data-packet network. The clock pulse is adjusted by controlling a difference between clock numbers of the first reference clock received in the clock source and clock numbers of the first reference clock between the initialization time and the reception times of the clock numbers of the first reference clock. Clock numbers of a second reference clock are transmitted to the clock source with the clock number of at least one second reference-clock source at individual times. The maximum difference between the first and the second reference clock is known. The difference between the clock pulse of the clock source and each second reference clock is limited to an adjustable threshold value.

A method for initializing a self-synchronizing coherent network Primary Reference Time Clock (cnPRTC) mesh includes: a self-synchronizing cnPRTC mesh is initialized during a start-up period; and a Universal Time Coordinated (UTC(k)) node connected to a selected cnPRTC node of the self-synchronizing cnPRTC mesh sets the selected cnPRTC node to a UTC(k) time provided by the UTC(k) node during the start-up period when a Global Navigation Satellite System (GNSS) system fails to provide the selected cnPRTC node with a GNSS time during the start-up period, wherein setting the selected cnPRTC node comprises directly inserting the UTC(k) time into a clock combiner module of the selected cnPRTC node, the inserted UTC(k) time replacing weighted times provided to the selected cnPRTC node by local time sources and remote time sources.

A detection apparatus according to one embodiment includes an internal clock, an oscillator unit that generates oscillation every time a temporal condition is met, an oscillation receiver unit that detects oscillation, a measurement unit that measures a time from when the oscillator unit generates the oscillation to when the oscillation receiver unit detects the oscillation, a determination unit that determines a mode based on whether a time that is measured by the measurement unit is longer than a predetermined interval time, and a correction unit that determines whether to perform correction of deviation of the internal clock based on a reference time when it is determined that the mode is a specific mode, and corrects the internal clock when determining that the correction is performed.

A relay device relaying communication between a plurality of masters and a plurality of slaves via a communication network is provided. The relay device includes a time synchronization support unit configured to set a lower communication priority for a time synchronization communication frame transmitted from a master when a clock accuracy required for a function of the master is relatively low.

Methods and systems are disclosed maintaining playback of content at a target or desired playback time. A playback device may be configured to compare a current playback time of a content asset to a target playback time of the content asset and to determine, for each comparison, whether a difference between the current playback time and the target playback time has reached a threshold. Based on determining that the difference between the current playback time and the target playback time has reached a threshold, the playback device may seek to the target playback time of the content asset. The playback device may be configured to repeatedly perform the comparing, determining and seeking operations in order to maintain the current playback time of the content within the threshold of the target playback time.

A method for initializing a self-synchronizing coherent network Primary Reference Time Clock (cnPRTC) mesh includes: a self-synchronizing cnPRTC mesh is initialized during a start-up period; and a Universal Time Coordinated (UTC(k)) node connected to a selected cnPRTC node of the self-synchronizing cnPRTC mesh sets the selected cnPRTC node to a UTC(k) time provided by the UTC(k) node during the start-up period when a Global Navigation Satellite System (GNSS) system fails to provide the selected cnPRTC node with a GNSS time during the start-up period, wherein setting the selected cnPRTC node comprises directly inserting the UTC(k) time into a clock combiner module of the selected cnPRTC node, the inserted UTC(k) time replacing weighted times provided to the selected cnPRTC node by local time sources and remote time sources.

The present disclosure relates to a device and methods for clock synchronization. The device may include a first synchronization component and one or more second synchronization components. The first synchronization component may be configured to transmit a first synchronization signal to the one or more second synchronization components. Each second synchronization component of the one or more second synchronization components may be configured to generate a second synchronization signal based on the first synchronization signal and transmit the second synchronization signal to one or more detectors. The second synchronization signal may be configured to reset a clock of a detector of the one or more detectors corresponding to the each second synchronization component.