The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
The modern industrial and substation automation Ethernet networks have demanding requirements about high availability. Recently, the IEEE 802.1 WG proposes the IEEE 802.1aq, also known as Shortest Path Bridging, to manage Ethernet redundant networks. The IEEE 1588 protocol can exploit the SPB capabilities to manage multiple paths in order to improve synchronization availability. In the paper, the...
This paper deals with time synchronization of devices attached to a smart grid, whose accuracy tightly depends on the accurate estimation of the Time of Arrival (ToA) of the synchronization related messages sent over the power line communication systems. Usually smart grids are quite complex “systems of heterogeneous systems”: the aim of this paper is to suggest a ToA detection mechanism that can...
Real-time networks for substations automation systems are based on ICT technologies and they may take great advantages from ultra recent network technological improvements. A careful evaluation of the performance enhancement is required. Due to cost and system complexity, such an analysis can be performed only using a dedicated simulation environment, but the currently available simulation libraries...
The paper deals with a new test bench for the assessment of time-related performance of wireless systems implementing the IEEE 802.15.4 with the Chirp Spread Spectrum (CSS) physical layer. The test bench has been designed in order to clearly evaluate the timestamping capabilities of an FPGA-based implementation of the IEEE 802.15.4 CSS. The key features are the full bandwidth capability and the extreme...
In modern real-time Ethernet networks for substation automation, several protocols are adopted to guarantee the strict synchronization and availability requirements imposed by applications. The management of these networks is more and more complex, since several (cross-influencing) configuration parameters affect the performance of the overall system. In this paper the attention has been focused on...
PLC is the acronym for ??PowerLine Communication?? and means data communications via power wiring. PLC was initially used for tele-protection and tele-monitoring of electrical substations by means of high voltage power lines, in order to avoid costs of microwave or fiber optic links. More recently, PLC has been also adopted for automatic smart metering. However, only with the advent of low-cost digital...
Clock synchronization is essential to support time-based medium access scheduling and distributed control over industrial networks relying on Real-Time Ethernet (RTE). PROFINET IO is one of the most widely used field-buses in large automation plants. The PROFINET IO Isochronous Real Time (IRT) implementation includes a Precision Transparent Clock Protocol (PTCP) for network-level synchronization....
Managing a large building construction site is a really complex task. Nowadays, many controllers have to daily check the site collecting information in order to inform managers about the construction progress. Recently, several software applications, compatible and integrated in most of commercial CAD tools, have been developed to help managers in collecting information. These tools furnish the managers...
This paper deals with the adoption of wireless communications in industrial automation. Most diffuse wireless systems require the deployment of a fixed infrastructure, with sufficient nodes acting as coordinators; this approach is typically applied also in automation. Conversely, a decentralized wireless solution is here proposed: it is based on a synchronous and connection-oriented protocol studied...
An increasing number of distributed measurement and control applications requires that network nodes are able to estimate the position and the time measured by other devices on a common spatio-temporal reference frame. Accurate packet timestamping is a necessary condition to achieve this goal. However, in the case of wireless networks, timestamping accuracy is generally quite poor due to the combination...
A reliable source of time is a fundamental requirement for safety critical applications. For this class of applications, synchronization protocols like the IEEE1588 standard, can be adopted. This type of synchronization protocols was designed to achieve very precise clock synchronization, but they may not be sufficient to ensure safety of the whole system. For example an instability of the local oscillator...
The work presented in this paper is related with time synchronization for wireless networks. In particular, it is focused on the proposal and experimental evaluation of a low-cost and high precision timestamping technique based on Ultra Wide Band (UWB) signalling. In recent years, the use of such systems has gained an increasing success thanks to their robustness to interferers and multipath. In this...
The paper presents a case study regarding a real PROFINET IO network for factory automation. The aim of the study is the evaluation of the time related parameter of a real network. A large factory automation plant has been chosen as testbed since PROFINET IO RT Class 1 and 2 (unsynchronized) are mainly used in those applications. The analyzed network has a high number of distributed IO, actuators...
The IEEE1588 became in the last years the de-facto solution to obtain a strict synchronization over a local area network. The purpose of the paper is to analyze the uncertainty sources that affect a software-only implementation of the IEEE1588 (the so called PTPd) based on off-the-shelf PC components. A careful analysis of timestamp mechanism and time management in a PC platform with an Operating...
Synchronized Phasor Measurement Units (PMUs) are becoming a key element of monitoring, protection, control and state estimation applications in power systems and are the basis for the implementation of Wide Area Monitoring Systems (WAMSs). This paper investigates the possibility of using a software-only PTP (Precision Time Protocol) synchronization method to synchronize different Phasor Measurement...
MOX sensors are widely used in several application fields: environmental monitoring, home automation, food control, and so on. Research activities in this topic are oriented towards new materials and nanotechnologies, thus requiring new instruments for the sensor characterization and management. Often, in order to improve selectivity, sensitivity, stability, the sensor is heated according to purposely-designed...
The growing interest towards green and efficient use of electrical energy has recently pushed the industry of street light control systems. In the past, very simple on/off switching mechanism based on daylight sensing and cyclic preventive maintenance procedures were adopted. Nowadays, intelligent control systems offering remote supervision have strongly contributed to a change in perspective in maintenance...
Today, wireless sensor technology is based on monolithic transceivers that optimize cost but have a rigid hardware architecture. In this paper, a new architecture for wireless sensors is presented. It is based on a software-defined radio concept and shows impressive adaptability to external conditions. The proposed architecture, which is called the wireless ultrasmart sensor (WUSS), enables the use...
Nowadays the IEEE1588 synchronization protocol has been adopted in a growing number of fields, from automation to telecommunication systems. Usually, the quality of the services provided by these applications requires an accurate and reliable time synchronization. Several solutions have been already proposed to achieve these goals. However, the statistical instruments provided in the standard (PTP...
This paper deals with the application of the Chirp Spread Spectrum (CSS) modulation for the synchronization of wireless sensors. Chirp modulation is a well known technique for precise localization, originally developed for RADAR applications. When CSS is used for communication purposes, radio frequency pulses are modulated in order to convey also user data. This approach allows for robustness, thanks...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.