Wireless Fault-Tolerant Controllers in Cascaded Industrial Workcells Using Wi-Fi and Ethernet

A Wireless Networked Control System using 802.11b is used to model fault-tolerance at the controller level of an industrial workcell. The fault-tolerance study in this paper presents the cascading of two independent workcells where each controller must be able to handle the load of both cells in case of failure of the other one. The intercommunication is completely wireless between the cells and this feature is investigated. The model incorporates unmodified 802.11b and 802.11g for communication. Sensors send sampled data to both controllers and the controllers to exchange a watchdog. The fault-free and faulty models are both simulated using OPNET Network Modeler. External interference on the critical intercommunication link is also investigated. Results of simulations are presented based on a 95% confidence analysis, guaranteeing correct system performance.

Time Delay Characteristic of Industrial Wireless Networks Based on IEEE 802.15.4a

The IEEE 802.15.4a standard provides a framework for low-data-rate communication systems,typically sensor networks.In this paper,we established a realistic environment for the time delay characteristic of industrial network based on IEEE 802.15.4a.Several sets of practical experiments are conducted to study its various features,including the effects of 1） numeral wireless nodes,2） numeral data packets,3） data transmissions with different upper-layer protocols,4） physical distance between nodes,and 5） adding and reducing the number of the wireless nodes.The results show that IEEE 802.15.4a is suitable for some industrial applications that have more relaxed throughput requirements and time-delay.Some issues that could degrade the network performance are also discussed.

Precoder Design and Impulsive Noise Mitigation Scheme for Industrial Wireless Communications

In industrial wireless scenarios,the impulsive noise(IN)incurred by machine running or operation causes a serious influence on the powerlimited industrial wireless communications.It is challenging to ensure efficient and reliable transmission with quality of service(QoS)guarantee for machinetype communication devices(MTCDs).Considering the IN in the industrial process,this paper establishes the multiuser multiple-input single-output(MU-MISO)orthogonal frequency division multiplexing(OFDM)system model,which combines transmitter and receiver design.Two precoding schemes are designed to improve communication effectiveness at the transmitter.More specifically,the precoder design scheme which combines semi-definite relaxation(SDR)with difference-of-two-convex-function(D.C.)iterative algorithm,is developed by utilizing the Dinkelbach method to improve the system effectiveness.To decrease the computational complexity,we devise the quadratic-based fractional programming(QFP)algorithm,which decouples the variables by using a quadratic transform method.On this basis,the IN mitigation scheme is studied to reduce the system error rate(SER)at the receiver.With the goal of improving the reliability of industrial wireless communications,we propose a hybrid nonlinear IN mitigation(HNINM)scheme and then derive its closed-form expression of SER.The simulation results show that the proposed QFP algorithm achieves superior performance while the HNINM scheme decreases the SER of industrial wireless communications.

Novel MAC Layer Proposal for URLLC in IndustrialWireless Sensor Networks

Ultra-reliable and low-latency communications(URLLC) has become a fundamental focus of future industrial wireless sensor net-works(IWSNs). With the evolution of automation and process control in industrial environments, the need for increased reliabilityand reduced latencies in wireless communications is even pronounced. Furthermore, the 5G systems specifically target the URLLCin selected areas and industrial automation might turn into a suitable venue for future IWSNs, running 5G as a high speed inter-process linking technology. In this paper, a hybrid multi-channel scheme for performance and throughput enhancement of IWSNsis proposed. The scheme utilizes the multiple frequency channels to increase the overall throughput of the system along with theincrease in reliability. A special purpose frequency channel is defined, which facilitates the failed communications by retransmis-sions where the retransmission slots are allocated according to the priority level of failed communications of different nodes. Ascheduler is used to formulate priority based scheduling for retransmission in TDMA based communication slots of this channel.Furthermore, in carrier-sense multiple access with collision avoidance(CSMA/CA) based slots, a frequency polling is introducedto limit the collisions. Mathematical modelling for performance metrics is also presented. The performance of the proposed schemeis compared with that of IEEE802.15.4e, where the performance is evaluated on the basis of throughput, reliability and the num-ber of nodes accommodated in a cluster. The proposed scheme offers a notable increase in the reliability and throughput over theexisting IEEE802.15.4e Low Latency Deterministic Networks(LLDN) standard.

Research on the Development of 5G Wireless Communication in the Industrial Field

The development of science and technology is the key to changing human life and promoting social and economic development.As a product of technological development,the widespread application of communication technology has brought a brand new“dawn”to the development of human society.5G wireless communication technology is an advanced wireless communication technology that has recently developed.With the advantages of low energy consumption and high network speed,5G technology has shown very bright development prospects in various fields today.Government,operators and equipment providers are actively promoting and deploying 5G technology,and all links in the industry chain are mature.It is expected that the future market size will reach 17 trillion,especially in today’s industrial field,the application of 5G technology will further enhance work efficiency,ensure work quality,and promote good development in the industrial field.Based on this,this paper will study the development of 5G wireless technology in the industrial field,so as to provide corresponding reference for the good application of 5G technology in the industrial field.

Comprehensive Analysis of Secure Data Aggregation Scheme for Industrial Wireless Sensor Network

As an Industrial Wireless Sensor Network(IWSN)is usually deployed in a harsh or unattended environment,the privacy security of data aggregation is facing more and more challenges.Currently,the data aggregation protocols mainly focus on improving the efficiency of data transmitting and aggregating,alternately,the aim at enhancing the security of data.The performances of the secure data aggregation protocols are the trade-off of several metrics,which involves the transmission/fusion,the energy efficiency and the security in Wireless Sensor Network(WSN).Unfortunately,there is no paper in systematic analysis about the performance of the secure data aggregation protocols whether in IWSN or in WSN.In consideration of IWSN,we firstly review the security requirements and techniques in WSN data aggregation in this paper.Then,we give a holistic overview of the classical secure data aggregation protocols,which are divided into three categories:hop-by-hop encrypted data aggregation,end-to-end encrypted data aggregation and unencrypted secure data aggregation.Along this way,combining with the characteristics of industrial applications,we analyze the pros and cons of the existing security schemes in each category qualitatively,and realize that the security and the energy efficiency are suitable for IWSN.Finally,we make the conclusion about the techniques and approach in these categories,and highlight the future research directions of privacy preserving data aggregation in IWSN.

A routing algorithm for industrial wireless network based on ISA100.11a

ISA100.11 a industrial wireless network standard is based on a deterministic scheduling mechanism.For the timeslot delay caused by deterministic scheduling,a routing algorithm is presented for industrial environments.According to timeslot,superframe,links,channel and data retransmission of deterministic scheduling mechanisms that affect the design of the routing algorithm,the algorithm selects the link quality,timeslot delay and retransmission delay as the routing criteria and finds the optimum communication path by k shortest paths algorithm.Theoretical analysis and experimental verification show that the optimal paths selected by the algorithm not only have high link quality and low retransmission delay,but also meet the requirements of the deterministic scheduling.The algorithm can effectively solve the problem of packet loss and transmission delay during data transmission,and provide a valuable solution for efficient data transmission based on determinacy.

Method to deploy wireless relays in industrial wireless monitoring

In light of demands for wireless monitoring and the characteristics of wireless channel,a complete deployment method containing channel survey,path loss estimation,and gradient grade of wireless relay nodes is proposed.It can be proved by experiments that under the premise of meeting the requirements of real-time and redundant-topology,the total number of relay nodes could be minimized by using the proposed method.

Dynamic Time Division Multiple Access Algorithm for Industrial Wireless Hierarchical Sensor Networks

Industrial wireless sensor networks adopt a hierarchical structure with large numbers of sensors and routers. Time Division Multiple Access (TDMA) is regarded as an efficient method to reduce the probability of confliction. In the intra-cluster part, the random color selection method is effective in reducing the retry times in an application. In the inter-cluster part, a quick assign algorithm and a dynamic maximum link algorithm are proposed to meet the quick networking or minimum frame size requirements. In the simulation, the dynamic maximum link algorithm produces higher reductions in the frame length than the quick assign algorithm. When the number of routers is 140, the total number of time slots is reduced by 25%. However, the first algorithm needs more control messages, and the average difference in the number of control messages is 3 410. Consequently, the dynamic maximum link algorithm is utilized for adjusting the link schedule to the minimum delay with a relatively high throughput rate, and the quick assign algorithm is utilized for speeding up the networking process.

Hybrid Power Bank Deployment Model for Energy Supply Coverage Optimization in Industrial Wireless Sensor Network

Energy supply is one of the most critical challenges of wireless sensor networks(WSNs)and industrial wireless sensor networks(IWSNs).While research on coverage optimization problem(COP)centers on the network’s monitoring coverage,this research focuses on the power banks’energy supply coverage.The study of 2-D and 3-D spaces is typical in IWSN,with the realistic environment being more complex with obstacles(i.e.,machines).A 3-D surface is the field of interest(FOI)in this work with the established hybrid power bank deployment model for the energy supply COP optimization of IWSN.The hybrid power bank deployment model is highly adaptive and flexible for new or existing plants already using the IWSN system.The model improves the power supply to a more considerable extent with the least number of power bank deployments.The main innovation in this work is the utilization of a more practical surface model with obstacles and training while improving the convergence speed and quality of the heuristic algorithm.An overall probabilistic coverage rate analysis of every point on the FOI is provided,not limiting the scope to target points or areas.Bresenham’s algorithm is extended from 2-D to 3-D surface to enhance the probabilistic covering model for coverage measurement.A dynamic search strategy(DSS)is proposed to modify the artificial bee colony(ABC)and balance the exploration and exploitation ability for better convergence toward eliminating NP-hard deployment problems.Further,the cellular automata(CA)is utilized to enhance the convergence speed.The case study based on two typical FOI in the IWSN shows that the CA scheme effectively speeds up the optimization process.Comparative experiments are conducted on four benchmark functions to validate the effectiveness of the proposed method.The experimental results show that the proposed algorithm outperforms the ABC and gbest-guided ABC(GABC)algorithms.The results show that the proposed energy coverage optimization method based on the hybrid power bank deployment model generates more accurate results than the results obtained by similar algorithms(i.e.,ABC,GABC).The proposed model is,therefore,effective and efficient for optimization in the IWSN.

A Methodology for Reliability of WSN Based on Software Defined Network in Adaptive Industrial Environment

As communication technology and smart manufacturing have developed, the industrial internet of things(IIo T)has gained considerable attention from academia and industry.Wireless sensor networks(WSNs) have many advantages with broad applications in many areas including environmental monitoring, which makes it a very important part of IIo T. However,energy depletion and hardware malfunctions can lead to node failures in WSNs. The industrial environment can also impact the wireless channel transmission, leading to network reliability problems, even with tightly coupled control and data planes in traditional networks, which obviously also enhances network management cost and complexity. In this paper, we introduce a new software defined network(SDN), and modify this network to propose a framework called the improved software defined wireless sensor network(improved SD-WSN). This proposed framework can address the following issues. 1) For a large scale heterogeneous network, it solves the problem of network management and smooth merging of a WSN into IIo T. 2) The network coverage problem is solved which improves the network reliability. 3) The framework addresses node failure due to various problems, particularly related to energy consumption.Therefore, it is necessary to improve the reliability of wireless sensor networks, by developing certain schemes to reduce energy consumption and the delay time of network nodes under IIo T conditions. Experiments have shown that the improved approach significantly reduces the energy consumption of nodes and the delay time, thus improving the reliability of WSN.

Adaptive Power Control for mutual Interference Avoidance in Industrial Internet-of-Things

With the vigorous development of the Internet of Things and 5G technology, such as machine-to-machine and device-todevice, all kinds of data transmission including environmental monitoring and equipment control strengthens the key role of wireless sensor networks in the large-scale wireless communication system. However, especially in the complex industrial wireless applications, the low utilization efficiency of the limited wireless radio resource enhances the coexistence problem between heterogeneous networks. In this paper, from the severe mutual interference point of view, a mathematical model regarding cumulative interferences in the industrial wireless sensor networks is described. Then, from the perspective of mutual interference avoidance, an adaptive power control scheme is proposed in order to handle the normal communication needs on both the primary link and the secondary link. At last, nonlinear programming is taken to solve the corresponding optimization problem. Some typical analyses are given to verify the effectiveness of the proposed scheme on optimizing the tradeoff between the system throughput and energy consumption. Especially, the energy-efficiency of the novel scheme for Industrial Internet of Things is also analysed. Results show that the proposed power control is efficient. The throughput could be enhanced and the energy consumption could be reduced with the guarantee of mutual interference avoidance.

文华东方酒店采用Ruckus Wireless智能Wi-Fi解决方案

智能无线网络公司Ruckus Wireless日前宣布,文华东方酒店集团选择其ZoneFlex智能Wi-Fi产品和技术为旗下遍及亚太和欧洲的酒店提供各种访客和管理服务支持。文华东方酒店是Ruckus在过去60天里全球新签订的65家酒店客户之一。

Design of IEEE1451.5 WTIM for Industrial Network Based on Ubiquitous Sensor Network

Recently, the use of ubiquitous sensor network technology has spread vastly. The ubiquitous sensor networks are widely de- ployed in factory auttxnation as they provide effective measuring solution for instruments. The wired/wireless network module, which provides the interface to connect to the u-sensor network, is needed but there is no perfect standardization about the interface. In this situation, the interface compatibility between measuring instrument can be maintained using the IEEEI451 international standard. In this paper, the Wireless Transducer Interface Mcduie （WTIM） based on IEEE1451.5 was designed. It coxnects to the measuring instnmnt, like the muiti-meter, power meter, and etc., to support the RS232 interface. As these devices cannot connect to network without a mod- ule, we use the WTIM to help these devices connect to network sys- ton. Its ftmction was verified through the ubiquitous network connection and data transfer between monitoring PC and measuring instrument. This technology is expected to reduce cost in order to construct the wireless industry automation system using existing devices.

Broadcom与Skyhook Wireless公司提供先进的Wi-Fi定位服务

全球有线和无线通信半导体市场的领导者Broadcom（博通）公司宣布它将对其定位服务（LBS）基础设施进行升级，以便在其定位服务系列中添加Wi-Fi定位。Broadcom公司将充分利用它在GPS和Wi-Fi两种技术上的领先地位，并使用由Skyhook Wireless公司（它在开发Wi-Fi定位方面处于领军地位）开发的Wi-Fi定位系统，集成、部署和提供这种新的功能。

Silicon Labs Wireless Xpress模块免编程实现蓝牙和Wi-Fi连接

Silicon Labs(亦称“芯科科技”发布了全新的Wireless Xpress解决方案,帮助开发人员一天内连接并运行物联网应用,且无需进行软件开发。Silicon Labs的Wireless Xpress提供了基于配置的开发体验,满足了开发人员的所有需求,这包括经过认证的Bluetooth 5 Low Energy(LE)和Wi Fi模块、集成的协议栈和易于使用的工具。

Silicon Labs Wireless Xpress模块免编程实现蓝牙和Wi-Fi连接

Silicon Labs日前发布了全新的Wireless Xpress解决方案，该方案可帮助开发人员在一天内连接并运行物联网应用，且无需进行软件开发。

Wireless Xpress模块免编程实现蓝牙和Wi-Fi连接

芯科科技日前发布了全新的Wireless Xpress解决方案,帮助开发人员-天内连接并运行物联网应用,且无需进行软件开发.Silicon Labs的Wireless Xpress提供了基于配置的开发体验,满足了开发人员的所有需求,这包括经过认证的Bluetooth 5 Low Energy（LE）和Wi-Fi模块、集成的协议栈和易于使用的工具.

CSR携手Skyhook Wireless，合作开发Wi-Fi定位技术

无线技术提供商CSR公司和Wi-Fi定位系统及XPS 2.0混合定位系统的制造商Skyhook Wireless公司日前宣布，合作为CSR的Wi-Fi芯片引入先进的定位能力。Skyhook Wireless的核心技术——Wi-Fi定位系统（WPS）是一个软件，它能够监测到Wi-Fi接入点并与已知地理位置点数据库进行比较，从而提供精确的位置信息。通过将CSR的UniFi、嵌入式Wi-Fi芯片及GPS定位解决方案与Skyhook的定位能力进行整合，使设备制造商能够更加轻松地支持和推出位置服务，以满足消费者的位置需求。

爱特梅尔与H&D Wireless携手 提供嵌入式Wi-Fi解决方案

爱特梅尔公司（Atmel Corporation）宣布与H＆D Wireless公司合作，推出用于爱特梅尔32位AVR？微控制器的IEEE802．11b＋gWi—Fi解决方案。在这项合作中，H＆D Wireless将提供SPB104 Wi—Fi扩展板卡，该板卡能够通过sD卡插座轻易连接AVR32UC3评测工具套件。