| 1. |
- Yang, D, et al.
(författare)
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CCA-Embedded TDMA Enabling Acyclic Traffic in Industrial Wireless Sensor Networks
- 2013
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Ingår i: Ad hoc networks. - Elsevier : Elsevier BV. - 1570-8705 .- 1570-8713. ; 11:3, s. 1105-1121
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Tidskriftsartikel (refereegranskat)abstract
- A growing trend in the automation industry is to use wireless technologies to reduce cable costs and deployment time, unlock stranded information in deployed devices and enable wireless control applications. The WirelessHART protocol is the first open and interoperable industrial wireless sensor network standard, which proposes a combination of time division multiple access (TDMA) and channel hopping as a medium access control (MAC) protocol. TDMA is a schedule-based protocol, which is suitable for predictable cyclic traffic. However, for burst acyclic traffic, TDMA degenerates into an inefficient slotted ALOHA. In this article, we propose a complementary mechanism to TDMA, CCA-Embedded TDMA, which can be applied to improve the transmission efficiency and system stability of TDMA-based systems such as the WirelessHART protocol. A Markov model is proposed to evaluate the efficiency of system throughput and expected delay of CCA-Embedded TDMA. Furthermore, we show by analytical and simulation results that our proposed CCA-Embedded TDMA scheme can increase the throughput by 100% and reduce the expected delay by 75% for a common scenario. We also implement CCA-Embedded TDMA into an embedded system as a part of the WirelessHART MAC protocol. The experimental results verify the efficiency of CCA-Embedded TDMA and its backward compatibility with the WirelessHART protocol.
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| 2. |
- Ma, Jian, et al.
(författare)
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A Reliable Handoff Mechanism for Mobile Industrial Wireless Sensor Networks
- 2017
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Ingår i: Sensors. - : MDPI AG. - 1424-8220. ; 17:8
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Tidskriftsartikel (refereegranskat)abstract
- With the prevalence of low-power wireless devices in industrial applications, concerns about timeliness and reliability are bound to continue despite the best efforts of researchers to design Industrial Wireless Sensor Networks (IWSNs) to improve the performance of monitoring and control systems. As mobile devices have a major role to play in industrial production, IWSNs should support mobility. However, research on mobile IWSNs and practical tests have been limited due to the complicated resource scheduling and rescheduling compared with traditional wireless sensor networks. This paper proposes an effective mechanism to guarantee the performance of handoff, including a mobility-aware scheme, temporary connection and quick registration. The main contribution of this paper is that the proposed mechanism is implemented not only in our testbed but in a real industrial environment. The results indicate that our mechanism not only improves the accuracy of handoff triggering, but also solves the problem of ping-pong effect during handoff. Compared with the WirelessHART standard and the RSSI-based approach, our mechanism facilitates real-time communication while being more reliable, which can help end-to-end packet delivery remain an average of 98.5% in the scenario of mobile IWSNs.
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| 3. |
- Yang, Dong, et al.
(författare)
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Applying Industrial Wireless Sensor Networks to Welder Machine System
- 2014
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Ingår i: IPSN 2014 - Proceedings of the 13th International Symposium on Information Processing in Sensor Networks (Part of CPS Week). ; , s. Art. no. 6835794-
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Konferensbidrag (refereegranskat)abstract
- Despite lots of research efforts in the area of Industrial Wireless Sensor Networks (IWSNs), there is a lack of really practical IWSN implementations, deployments and in-field experiments. This demo presents the design and implementation of an IWSN for welder machine systems based on the first IWSN standard WirelessHART. The goal of this work is to find the problems and challenges from IWSN standard to implementation, and motivate other designers to explore more IWSN applications.
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