Proceedings ArticleDOI
Enhancements to the time synchronization standard IEEE-1588 for a system of cascaded bridges
Jurgen Jasperneite,K. Shehab,Karl Weber +2 more
- pp 239-244
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TLDR
In this paper, a bypass clock instead of the boundary clock is proposed as an enhancement of the IEEE-1588 standard for bridged networks, where the local clock adjustment can be modeled by a corresponding control loop.Abstract:
The IEEE-1588 standard for a high precision time synchronization now exists since 2002. For using this standard in bridged networks a so-called boundary clock is defined, where the local clock adjustment can be modeled by a corresponding control loop. At the field level of industrial automation systems, the line topology is very important. By using Ethernet at the field level, the resulting chain of bridges leads to a cascade of control loops and may lead to instabilities and deviations of the distributed clocks, which are not acceptable. For this application a bypass clock instead of the boundary clock is proposed as an enhancement of the IEEE-1588 standard. The effectiveness of this extension to be evaluated by simulation technique.read more
Citations
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Proceedings ArticleDOI
Out-Degree Based Clock Synchronization In Wireless Networks Using Precision Time Protocol
Monika Bansal,Apurva Gupta +1 more
TL;DR: An extension of Precision Time Protocol to enable energy-efficient clock synchronization between the nodes within Wireless Sensor Network (WSN) to reduce clock convergence time and energy needed by considering out-degree of clocks without sacrificing synchronization accuracy is proposed.
Proceedings ArticleDOI
Fieldbus performance prediction using DOE with D-Optimal analysis
Petru Papazian,Mircea Babaitl +1 more
TL;DR: This paper introduces a new approach of fieldbus analysis based on statistical methods combined with “Design of Experiment”, aiming to identify the effects of various parameters upon fieldbus performances.
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TL;DR: In this article, a 3D measuring apparatus for optically scanning and measuring an environment, comprising a measuring head (12) having a light transmitter (17), a light receiver (21), and a control and evaluation device (22) for a plurality of measurement points (X) in each case at least the distance (d) to the object (O) determined, is used as a power supply in the measuring head.
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Time synchronization in a communications network with a plurality of network nodes
TL;DR: In this paper, a plurality of sub-networks are defined in the communications network, and each of the sub-network consists of a local master node and a local slave node.
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Device and method for time synchronization in distributed control system
TL;DR: In this article, the authors present a method for time synchronization in a distributed control system that includes the steps of: when a sync is received from a master-side, confirming both a reception time point of the corresponding sync and a compensation time point from a previous frequency, and determining if a result obtained by confirming the two time points corresponds to a preset Frequency Compensation Interval (FCI); performing only a time offset compensation operation when the result obtained from confirming the time points does not correspond to the preset FCI; and performing both time offset and frequency compensation operations when the results
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Journal ArticleDOI
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TL;DR: A protocol is provided in this standard that enables precise synchronization of clocks in measurement and control systems implemented with technologies such as network communication, local computing, and distributed objects.
Proceedings ArticleDOI
IEEE 1588 standard for a precision clock synchronization protocol for networked measurement and control systems
J C. Eidson,Kang B. Lee +1 more
TL;DR: This paper discusses the major features and design objectives of the IEEE-1588 standard, designed to serve the clock synchronization needs of industrial systems, and recent performance results of prototype implementations of this standard in an Ethernet environment are presented.
Journal ArticleDOI
Precision synchronization of computer network clocks
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