Evaluation of DECT for low latency real-time industrial control networks

c. 1905. Pale yellow rayon faille Princess line dress with a bobbinet overlay appliquéd with cream wool Art Nouveau lilies and finished with machine-made Chantilly lace flounces, closing in back, with short sleeves and a floor-length skirt. The dress is made from long fitted panels without a waist seam. Eight shaped pieces extend from the bodice to the skirt hem: two narrow front panels with a center seam, two side-front panels, two side-back panels, and two back panels with a center-back opening with twenty hooks. The panels narrow at the waist, curve over the hips and flare to the hem. The bodice portion of the dress is lined with white cotton just past the waist, made with one front panel shaped with two darts, and two back panels with one dart each. The dress has a scooped neckline in front and back, and has close-fitting sleeves ending above the elbow, made with one seam. The overlay is a two-twist bobbinet appliquéd before construction. Tightly woven cream wool was machine-sewn to the bobbinet with continuous lengths of pale yellow braided cord outlining columns of large stylized Art Nouveau lilies, stems, and leaves. The wool ground was then carefully cut away from the bobbinet, leaving the floral elements behind, as evidenced in part by a lily at the left front skirt hem missing its interior detail cut on one petal. There are two panels in the overlay, sewn to each other with a free-floating center-front seam and sewn to the dress at the neckline (dipping about 10.2 cm / 4 in. down from the edge at center-front), shoulders, and scyes. The overlay’s center-front seam runs precisely down the middle of a column of lilies, matching flower halves from left and right, and the join is reinforced by retaining the full, continuous length of the wool seam allowance and by leaving the interior details of flowers straddling the seam uncut. The bobbinet is, by its nature, stretchy and so drapes closely to the contours of the dress beneath; the panels wrap diagonally around the sides to the back, pulled up from their straight grain center-front seam into a bias angle in back where the columns of lilies form chevrons where they meet at center. The ends of the panels fold over the edges of the center-back opening of the underlying fabric. This draping results in the overlay skirt coming to a point just above the hem in front and rising almost to waist level in back. A machine-made Chantilly lace flounce, shorter in front and lengthening to the back, is added to the bottom edge of the bobbinet, so that the complete overlay skirt is 99.1 cm / 39 in. long in front as measured from the waistline, and 35.6 cm / 14 in. long in back. In the bodice, the flowers and leaves are applied individually to create a horizontal trim across the neckline, reaching slightly past its edge. At the front, an asymmetrical Chantilly flounce is sewn beneath the appliqué, shorter and fuller on the left side than on the right, hanging to the waist in front and ending in back at the shoulders. A lily is centered at the top of the bodice opening, sewn down on the right side and overlapping the opening to hook closed on the left. The sleeves are covered with the same bobbinet and appliqué, and are finished with a gathered, knotted band of the Chantilly lace. Machine-sewn and hand-sewn.https://scholars.unh.edu/bowen_collection/2008/thumbnail.jp

DECT-2020 New Radio: The Next Step Towards 5G Massive Machine-Type Communications

Massive machine type communications (mMTC) is one of the cornerstone services that have to be supported by 5G systems. 3GPP has already introduced LTE-M and NB-IoT, often referred to as cellular IoT, in 3GPP Releases 13, 14, and 15 and submitted these technologies as part of 3GPP IMT-2020 (i.e., 5G) technology submission to ITU-R. Even though NB-IoT and LTE-M have shown to satisfy 5G mMTC requirements defined by ITU-R, it is expected that these cellular IoT solutions will not address all aspects of IoT and ongoing digitalization, including the support for direct communication between "things" with flexible deployments, different business models, as well as support for even higher node densities and enhanced coverage. In this paper, we introduce the DECT-2020 standard recently published by ETSI for mMTC communications. We evaluate its performance and compare it to the existing LPWAN solutions showing that it outperforms those in terms of supported density of nodes while still keeping delay and loss guarantees at the required level.Comment: Author-Submitted Paper to IEEE Communications Magazine, 7 pages, 4 figures, 2 table

Dissecting the impact of information and communication technologies on digital twins as a service

Recent advances on Edge computing, Network Function Virtualization (NFV) and 5G are stimulating the interest of the industrial sector to satisfy the stringent and real-time requirements of their applications. Digital Twin is a key piece in the industrial digital transformation and its benefits are very well studied in the literature. However, designing and implementing a Digital Twin system that integrates all the emerging technologies and meets the connectivity requirements (e.g., latency, reliability) is an ambitious task. Therefore, prototyping the system is required to gradually validate and optimize Digital Twin solutions. In this work, an Edge Robotics Digital Twin system is implemented as a prototype that embodies the concept of Digital Twin as a Service (DTaaS). Such system enables real-time applications such as visualization and remote control, requiring low-latency and high reliability. The capability of the system to offer potential savings by means of computation offloading are analyzed in different deployment configurations. Moreover, the impact of different wireless channels (e.g., 5G, 4G and WiFi) to support the data exchange between a physical device and its virtual components are assessed within operational Digital Twins. Results show that potentially 16% of CPU and 34% of MEM savings can be achieved by virtualizing and offloading software components in the Edge. In addition, they show that 5G connectivity enables remote control of 20 ms, appearing as the most promising radio access technology to support the main requirements of Digital Twin systems.This work was supported in part by the H2020 European Union/Taiwan (EU/TW) Joint Action 5G-eDge Intelligence for Vertical Experimentation (DIVE) under Grant 859881, in part by the H2020 5Growth Project under Grant 856709, in part by the Madrid Government (Comunidad de Madrid-Spain) through the Multiannual Agreement with Universidad Carlos III de Madrid (UC3M) in the line of Excellence of University Professors under Grant EPUC3M21, and in part by the context of the V PRICIT (Regional Program of Research and Technological Innovation)

Clock synchronisation for UWB and DECT communication networks

Synchronisation deals with the distribution of time and/or frequency across a network of nodes dispersed in an area, in order to align their clocks with respect to time and/or frequency. It remains an important requirement in telecommunication networks, especially in Time Division Duplexing (TDD) systems such as Ultra Wideband (UWB) and Digital Enhanced Cordless Telecommunications (DECT) systems. This thesis explores three di erent research areas related to clock synchronisation in communication networks; namely algorithm development and implementation, managing Packet Delay Variation (PDV), and coping with the failure of a master node. The first area proposes a higher-layer synchronisation algorithm in order to meet the specific requirements of a UWB network that is based on the European Computer Manufacturers Association (ECMA) standard. At up to 480 Mbps data rate, UWB is an attractive technology for multimedia streaming. Higher-layer synchronisation is needed in order to facilitate synchronised playback at the receivers and prevent distortion, but no algorithm is de ned in the ECMA-368 standard. In this research area, a higher-layer synchronisation algorithm is developed for an ECMA-368 UWB network. Network simulations and FPGA implementation are used to show that the new algorithm satis es the requirements of the network. The next research area looks at how PDV can be managed when Precision Time Protocol (PTP) is implemented in an existing Ethernet network. Existing literature indicates that the performance of a PDV ltering algorithm usually depends on the delay pro le of the network in which it is applied. In this research area, a new sample-mode PDV filter is proposed which is independent of the shape of the delay profile. Numerical simulations show that the sample-mode filtering algorithm is able to match or out-perform the existing sample minimum, mean, and maximum filters, at differentlevels of network load. Finally, the thesis considers the problem of dealing with master failures in a PTP network for a DECT audio application. It describes the existing master redundancy techniques and shows why they are unsuitable for the specific application. Then a new alternate master cluster technique is proposed along with an alternative BMCA to suit the application under consideration. Network simulations are used to show how this technique leads to a reduction in the total time to recover from a master failure

Increasing Safety Levels in Human-Machine Interaction by Beyond-5G Wireless Redundancy

Factory automation in the context of Industry 4.0/5.0 requires safety levels to satisfy more stringent and tight limits than those available so far. This goal is further challenged by the extension to the wireless environment of industrial shop floor communications that were traditionally based on cabled networks. Starting with wireless LANs, the trend towards the use of industrial wireless is fostered by the advent of fifth Generation (5G) private connectivity and is bound to increase its pace in the evolution towards 6G. In particular, the interaction of human operators with industrial robots and autonomous vehicles on the shop floor is posing stringent safety requirements that in turn push forward the dependability and reliability limits of wireless connectivity. To help achieve these limits, this paper proposes a dynamic redundancy mechanism based on the real-time activation/deactivation of radio bearers instantiated between mobile devices carried by humans and machines and multiple base stations, to achieve guaranteed upper bounds on packet loss probability in the communication of data related to operational safety control loops. An optimization problem is posed, and suitable heuristics are evaluated by simulation in a 5G and beyond wireless environment, aiming to dynamically maintain the required reliability levels with small computational effort

Proposition of a full deterministic medium access method for wireless network in a robotic application

International audienceToday, many network applications require shorter react time. Robotic field is an excellent example of these needs: robot react time has a direct effect on its task's complexity. Here, we propose a full deterministic medium access method for a wireless robotic application. This contribution is based on some low-power wireless personal area networks, like ZigBee standard. Indeed, ZigBee has identified limits with Quality of Service due to non-determinist medium access and probable collisions during medium reservation requests. In this paper, two major improvements are proposed: an efficient polling of the star nodes and a temporal deterministic distribution of peer-to-peer messages. This new MAC protocol with no collision offers some QoS faculties