Abstract: Method, device and system for detecting a disturbance, e.g., at least one short mechanical impact (shock or vibration) on a clock of a slave device by detecting a non-typical variation of a tracking error, i.e., a tracking error having a deviation that exceeds a predetermined threshold, wherein such a non-typical variation can be determined by the deviation from a statistical measure, e.g., a variance or a standard deviation, such that the determination of the quality of a clock signal is advantageously allowed and thus suitable counter-measures are provided. The method, device and system are applicable for all kinds of technical systems comprising slave devices that have a clock, e.g., devices in industrial and automation systems. The method, device and system are also applicable in communication systems that use a protocol to synchronize the clocks of its devices, e.g., Profinet.

Abstract: A method for time synchronization in a communications network having multiple nodes, wherein the nodes comprise a first node and at least one second node, where the first node generates first cycle counter states according to a reference clock frequency and the second node or nodes each generate second cycle counter states according to an internal clock frequency, where a time synchronization is carried out in sequential synchronization cycles, in which synchronization messages originating from the first node are sequentially transmitted from one node to another node, and a synchronization message transmitted by a node contains information used for time synchronization in the at least one second node receiving the synchronization message such that a time synchronization is performed in a given second node based on an estimation of a first cycle counter state and a compensation factor in combination with a linear quadratic regulator.

Abstract: A method for time synchronization in a communication network having a plurality of nodes each comprising a first node and at least one second node, wherein the first node generates first cycle counting states according to a reference cycle frequency and the second node generates second cycle counting states according to an internal cycle frequency, wherein time synchronization is performed in consecutive synchronization cycles in which, starting from the first node, synchronization messages are consecutively transferred from one node to a further node and a synchronization message transmitted by the node includes a segment of information that is used for time synchronization in the node receiving the synchronization message, wherein time synchronization is performed in the second node based on an estimate of a first cycle counting state in combination with a linear-quadratic regulator to obtain a synchronized time comprising a controlled first cycle counting state.

Abstract: A system and method for time synchronization in a communication network. The communication network includes a plurality of network nodes each having a respective internal clock, and a reference node having a reference clock and each configured transmits synchronization messages within the communication network. At least one network node is configured to determine an estimated reference clock time discretely upon arrival of a synchronization message at the at least one network node. To that end, the at least one network node includes a controller for determining a controlled time comprising a time-continuous estimate of the discreetly estimated reference clock time. The controller is configured to determine the controlled time based on an input that is extrapolated to an execution time instant of the controller, where the execution time instant is separated from the time instant of arrival of the synchronization message by a delay (?tdelay).

Abstract: A device and method for time synchronization in a communication network, wherein a virtual clock is produced by a controller in each network node based on the PROFINET-Standard and/or the Precision Transparent Clock Protocol. In contrast to known methods for estimating the time, the time of the virtual clock does not undergo sudden changes. The virtual clock includes a controlled, continuous path. As a result, the virtual clock is particularly suitable for time-critical applications. Here, the estimation of the time of a reference clock is improved by 18-35%. Accordingly, a markedly greater number of network nodes may be synchronized with a predetermined level of accuracy for the time synchronization.