A network system includes a synchronous master device to output a cooperative-operation timing signal in a cooperative-operation cycle, a time master station connected to a network, and a time slave station connected to the network. The time master station includes a master clock to count a time, and a master generation unit to generate master cooperative-operation-time information on the basis of the cooperative-operation timing signal and the time counted by the master clock. The time slave station includes a slave clock to count a time, and a slave generation unit to generate slave cooperative-operation-time information on the basis of the master cooperative-operation-time information and the time counted by the slave clock.

A method of synchronization of a communication device comprising a first and second communication ports, each of the first and second communication port being associated with a respective first and second time system, the method comprising a regular master synchronization process synchronizing regularly the first time system with an external synchronization server according to a time synchronization protocol; a regular slave synchronization process synchronizing regularly the second time system with the first-time system; detecting a loss of synchronization between the first and second time system; determining which of the first and second time system is desynchronized; and synchronizing the desynchronized time system with the other one.

An apparatus for controlling an automated installation has a first controller and a second controller that are connected to one another via a communication network. The first and second controllers each have a local clock and execute control tasks. The first and second controllers each further have a synchronization service that is used to synchronize the respective local clocks to a common reference clock. A timer repeatedly sends a trigger message to the first and second controllers. Each of the two controllers, on receiving the trigger message, determines a local time. The controllers interchange the respective local time and each compute a difference between their own local time and the local time obtained from the other controller. On the basis of the difference, each of the two controllers controls a local actuator.

An apparatus includes a receiver configured to receive a signal that has traveled an optical transmission line without returning output from an optical transmitting device and synchronize with the optical transmitting device in order to demodulate the signal; a dispersion compensator configured to compensate for wavelength dispersion caused by transmission of the signal; an acquisition circuit configured to acquire a transmitting timing at which the signal has been transmitted from the optical transmitting device; a calculation circuit configured to calculate a transmission time period from the optical transmitting device to the receiver from the transmitting timing and a receiving timing at which the signal has been received with the receiver; and an amount setting circuit configured to adjust a dispersion compensation amount of the dispersion compensator in accordance with the transmission time period.

A first synchronization signal for synchronization with a synchronization signal source is acquired from a first signal source. A first signal synchronized with the synchronization signal source is generated based on the first synchronization signal. A second synchronization signal for synchronization with the synchronization signal source is acquired from a second signal source different from the first signal source. A second signal synchronized with the synchronization signal source is generated based on the second synchronization signal. A timing signal synchronized with the synchronization signal source is generated based on the first signal of a synchronization device. A phase difference between the timing signal and the second signal is output. An offset is set so that there is no phase difference between the timing signal and the second signal based on the phase difference.

Systems and methods for measuring gas flux are disclosed. One method for calculating gas flux includes: receiving a master clock signal from a global positioning system (GPS) module; transmitting a clock synchronization signal that is based on the master clock signal to a measurement subsystem configured to measure environmental data, wherein the measurement subsystem comprises at least two clocks; receiving the environmental data from the measurement subsystem, wherein the environmental data is associated with the at least two clocks; and calculating gas flux based on the environmental data received from the measurement subsystem.

A time synchronization system includes a clock supply apparatus that includes an oscillator and generates a first time signal; and a time synchronization apparatus that includes a receiver which includes a fluctuation reducing unit provided on an outside of the clock supply apparatus, and which generates a second time signal based on a satellite signal. In addition, it is preferable that the time synchronization system is used in the network synchronization based on a master-slave synchronization method. Further, it is preferable that the oscillator is an atomic oscillator. In addition, it is preferable that the receiver and the clock supply apparatus are disposed at positions which are separated from each other. Further, it is preferable that the receiver and the clock supply apparatus are connected to each other via an optical fiber.

Methods, apparatus and systems for time mapping in a wireless communication are disclosed. In one embodiment, a method performed by a first network node of a wireless system is disclosed. The method comprises: receiving, from a controller of a time sensitive network (TSN), a configuration that comprises time information for scheduling; and converting the time information to converted time information of the wireless system.

A communication technique for synchronizing a set of radio nodes is described. In this communication technique, the radio node arbitrates (e.g., using a precision time protocol or PTP) with the other radio nodes based on a selection technique to select a synchronization master in the set of radio nodes. This synchronization master may be selected to have a predefined performance based on a type of communication environment of the set of radio nodes. For example, the type of communication environment may include overlap between at least one of the radio nodes in the set of radio nodes and a macrocell in a cellular-telephone network, or may exclude overlap between the set of radio nodes and the macrocell. Moreover, the synchronization master may specify time, frequency, and phase synchronization for the set of radio nodes. Thus, when the synchronization master is different from the radio node, the radio node synchronizes with the synchronization master.

The present disclosure provides systems and methods for proving an event. The system comprises a network of one or more beacon nodes and each beacon node is configured to: receive a request over the network for proving a time and location for an event, and the request comprises event data generated by a requesting entity; create a timestamp for the event using a clock of the beacon node, wherein the clock is synchronized to a trusted time source; generate a hash code for the timestamp and the event data and record the hash code to a ledger at the beacon node.