A trigger signal provided via a pulse-per-second input port of a network interface controller is detected. In response to the trigger signal, an internal hardware clock value of the network interface controller is recorded. The recorded internal hardware clock value is reported, wherein the reported internal hardware clock value is reported for use in determining a timing error of the network interface controller based at least in part on a comparison with a time value of another device that also received the trigger signal.

The invention relates to a method for providing a fault-tolerant global time via a time server in a distributed real-time computer system, wherein the time server comprises four components which are connected to one another via a bi-directional communication channel. At a priori defined periodic, internal synchronization times, each of the four components transmits an internal synchronization message, which is simultaneously transmitted to the other three components, from which each internal computer of a component determines a correction term for the tick counter contained in its component and corrects the reading of the local tick counter by this correction term.

Systems and methods for implementing a software emulation of a clock calibrated by the software based on sampling a hardware clock.

Example systems, apparatus, and methods receive audio information including a plurality of frames from a source device, wherein each frame of the plurality of frames includes one or more audio samples and a time stamp indicating when to play the one or more audio samples of the respective frame. In an example, the time stamp is updated for each of the plurality of frames using a time differential value determined between clock information received from the source device and clock information associated with the device. The updated time stamp is stored for each of the plurality of frames, and the audio information is output based on the plurality of frames and associated updated time stamps. A number of samples per frame to be output is adjusted based on a comparison between the updated time stamp for the frame and a predicted time value for play back of the frame.

A synchronization method includes obtaining a first timestamp difference of a packet on a target link. The first timestamp difference is a difference between a sending timestamp and a receiving timestamp of the packet at a first moment. The synchronization method further includes performing packet selection based on the first timestamp difference to obtain a second timestamp difference; obtaining a delay prediction value of the target link at the first moment, compensating for the second timestamp difference based on the delay prediction value to obtain a compensated timestamp difference; and performing time and/or clock synchronization based on the compensated timestamp difference. The second timestamp difference is compensated for based on the delay prediction value, that is, PDV noise introduced to the target link is compensated for. In this way, the PDV noise is reduced.

In one embodiment, a method receives a first time from a network device. The first time is derived from a first timing source in a first domain. The method receives a second time in a second domain from a second timing source. A difference time value is calculated between the first time and the second time. The method then sends the difference time value to the network device where the network device uses the difference time value to send a delay value to other computing devices to synchronize timing of the other computing devices in the second domain. The other computing devices are configured to synchronize the respective time using the delay value with mobile network devices to allow timing synchronization between the mobile network devices.

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a first user equipment (UE) may transmit, to a second UE, a system information block (SIB) that includes first timing information. The UE may transmit, to the second UE, second timing information associated with an update to the first timing information. Numerous other aspects are described.

Systems and methods to enable 5G system support for conveying time synchronization are provided. In some embodiments, a method performed by a wireless device for conveying external time domain information is provided. The method includes receiving a message in a first time domain used by the wireless device, the message comprising external time domain information; determining information about a second time domain based on the external time domain information; and conveying information about the second time domain to another node. In some embodiments, timing information is included into a GPRS Tunneling Protocol (GTP) payload, and the wireless device can get timing information directly from the data payload. This minimizes the RAN and/or gNB impact and adds the potential for multiple time domain support.

[Problem] To determine a time difference between clocks which, for example, are placed far apart from each other with high accuracy at low cost. [Solution] In a time comparison system 20, an intermediate station 21 disperses a single optical signal 21c in the spatial region using the optical complex amplitude modulation to simultaneously transmit the optical signal 21c to a plurality of comparative stations 22 and 23 apart from each other. The intermediate station 21 transmits the optical signal 21c while changing the transmission angle using phase modulation, performs intensity scanning for the reflected light c1 of the optical signal 21c, and detects the peak intensity to determine the directions of the comparative stations 22 and 23. The reflected light c1 of the optical signal 21c transmitted to the comparative stations 22 and 23 of which the direction have been determined, is detected to determine a round-trip propagation delay time between the intermediate station 21 and each of the comparative stations 22 and 23. The difference calculation unit 25 calculates a sum of time difference between each of times to and tb associated with the comparative stations 22 and 23 and the time tc associated with the intermediate station 21, and the determined propagation delay time to determine time information of each of the comparative stations 22 and 23. Based on the result of subtracting, from the time information of the comparative stations 22, the time information of the comparative stations 23, the time difference between the comparative stations 22 and 23 is determined.

Systems and methods for retaining synchronization between a CMTS core and an RPD when the RPD loses synchronization to a timing grandmaster, where both the core and the RPD are configured for individual synchronization in a slave configuration to the timing grandmaster, by operating the core as a boundary clock that sends timing information to the RPD.