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Real-time QoS support in wireless sensor networks: a survey
- In: 7th IFAC International Conference on Fieldbuses & Networks in Industrial & Embedded Systems - FeT’2007
, 2007
"... Abstract: Real-time wireless sensor networks are becoming more and more important by the requirement of message delivery timeliness in emerging new applications. Supporting real-time QoS in sensor networks faces severe challenges due to the wireless nature, limited resource, low node reliability, di ..."
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Cited by 132 (6 self)
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Abstract: Real-time wireless sensor networks are becoming more and more important by the requirement of message delivery timeliness in emerging new applications. Supporting real-time QoS in sensor networks faces severe challenges due to the wireless nature, limited resource, low node reliability, distributed architecture and dynamic network topology. There are tradeoffs between different application requirements including energy efficiency and delay performance. This paper studies the state of the art of current real-time solutions including MAC protocols, routing protocols, data processing strategies and cross-layer designs. Some research challenges and future design favors are also identified and discussed. Keywords: Real-time, wireless sensor networks, MAC, routing, cross-layer. 1.
Recent and Emerging Topics in Wireless Industrial Communications: A Selection
, 2007
"... In this paper we discuss a selection of promising and interesting research areas in the design of protocols and systemsforwirelessindustrialcommunications.Wehaveselected topicsthathaveeitheremergedashottopicsintheindustrial communicationscommunityinthelastfewyears(likewireless sensornetworks),orwhi ..."
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Cited by 96 (1 self)
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In this paper we discuss a selection of promising and interesting research areas in the design of protocols and systemsforwirelessindustrialcommunications.Wehaveselected topicsthathaveeitheremergedashottopicsintheindustrial communicationscommunityinthelastfewyears(likewireless sensornetworks),orwhichcouldbeworthwhileresearchtopicsin thenextfewyears(forexamplecooperativediversitytechniques for error control, cognitive radio/opportunistic spectrum access for mitigation of external interferences).
A Survey of Visual Sensor Networks
, 2009
"... Visual sensor networks have emerged as an important class of sensor-based distributed intelligent systems, with unique performance, complexity, and quality of service challenges. Consisting of a large number of low-power camera nodes, visual sensor networks support a great number of novel vision-bas ..."
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Cited by 81 (0 self)
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Visual sensor networks have emerged as an important class of sensor-based distributed intelligent systems, with unique performance, complexity, and quality of service challenges. Consisting of a large number of low-power camera nodes, visual sensor networks support a great number of novel vision-based applications. The camera nodes provide information from a monitored site, performing distributed and collaborative processing of their collected data. Using multiple cameras in the network provides different views of the scene, which enhances the reliability of the captured events. However, the large amount of image data produced by the cameras combined with the network’s resource constraints require exploring new means for data processing, communication, and sensor management. Meeting these challenges of visual sensor networks requires interdisciplinary approaches, utilizing vision processing, communications and networking, and embedded processing. In this paper, we provide an overview of the current state-of-the-art in the field of visual sensor networks, by exploring several relevant research directions. Our goal is to provide a better understanding of current research problems in the different research fields of visual sensor networks, and to show how these different research fields should interact to solve the many challenges of visual sensor networks.
Real-time query scheduling for wireless sensor networks
- in Real-Time Systems Symposium
, 2007
"... Abstract — Recent years have seen the emergence of wireless cyber-physical systems that must support real-time queries of physical environments through wireless sensor networks. This paper proposes Real-Time Query Scheduling (RTQS), a novel approach to conflict-free transmission scheduling for real- ..."
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Cited by 26 (12 self)
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Abstract — Recent years have seen the emergence of wireless cyber-physical systems that must support real-time queries of physical environments through wireless sensor networks. This paper proposes Real-Time Query Scheduling (RTQS), a novel approach to conflict-free transmission scheduling for real-time queries in wireless sensor networks. First, we show that there is an inherent trade-off between latency and real-time capacity in query scheduling. We then present three new real-time schedulers. The non-preemptive query scheduler supports high real-time capacity but cannot provide low response times to high priority queries due to priority inversions. The preemptive query scheduler eliminates priority inversions at the cost of reduced capacity. The slack stealing query scheduler combines the benefits of the preemptive and non-preemptive schedulers to improve the capacity while meeting query deadlines. We provide schedulability analysis for each scheduler. The analysis and advantages of our approach are validated through NS2 simulations. Index Terms — Query scheduling, schedulability analysis, sensor networks
Flow-Based Real-Time Communication in Multi-Channel Wireless Sensor Networks
"... Abstract. As many radio chips used in today’s sensor mote hardware can work at different frequencies, several multi-channel communication protocols have recently been proposed to improve network throughput and reduce packet loss for wireless sensor networks. However, existing work cannot utilize mul ..."
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Cited by 21 (6 self)
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Abstract. As many radio chips used in today’s sensor mote hardware can work at different frequencies, several multi-channel communication protocols have recently been proposed to improve network throughput and reduce packet loss for wireless sensor networks. However, existing work cannot utilize multiple channels to provide explicit guarantees for application-specified end-to-end communication delays, which are critical to many real-time applications such as surveillance and disaster response. In this paper, we propose MCRT, a multi-channel real-time communication protocol that features a flow-based channel allocation strategy. Because of the small number of orthogonal channels available in current mote hardware, MCRT allocates channels to network partitions formed based on many-to-one data flows. To achieve bounded end-to-end communication delay for every data flow, the channel allocation problem has been formulated as a constrained optimization problem and proved to be NP-complete. We then present the design of MCRT, which includes a channel allocation algorithm and a real-time packet forwarding strategy. Extensive simulation results based on a realistic radio model demonstrate that MCRT can effectively utilize multiple channels to reduce the number of deadlines missed in end-to-end communications. Our results also show that MCRT outperforms a state-of-the-art real-time protocol and two baseline multi-channel communication schemes. 1
Wireless Multimedia Sensor Networks: Current Trends and Future Directions
- SENSORS
, 2010
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Adaptive Fault Tolerant QoS Control Algorithms for Maximizing System Lifetime of Query-Based Wireless Sensor Networks
"... Abstract- Data sensing and retrieval in wireless sensor systems have a widespread application in areas such as security and surveillance monitoring, and command and control in battlefields. In query-based wireless sensor systems, a user would issue a query and expect a response to be returned within ..."
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Cited by 18 (11 self)
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Abstract- Data sensing and retrieval in wireless sensor systems have a widespread application in areas such as security and surveillance monitoring, and command and control in battlefields. In query-based wireless sensor systems, a user would issue a query and expect a response to be returned within the deadline. While the use of fault tolerance mechanisms through redundancy improves query reliability in the presence of unreliable wireless communication and sensor faults, it could cause the energy of the system to be quickly depleted. Therefore, there is an inherent tradeoff between query reliability vs. energy consumption in query-based wireless sensor systems. In this paper, we develop adaptive fault tolerant quality of service (QoS) control algorithms based on hop-by-hop data delivery utilizing “source ” and “path ” redundancy, with the goal to satisfy application QoS requirements while prolonging the lifetime of the sensor system. We develop a mathematical model for the lifetime of the sensor system as a function of system parameters including the “source ” and “path ” redundancy levels utilized. We discover that there exists optimal “source ” and “path ” redundancy under which the lifetime of the system is maximized while satisfying application QoS requirements. Numerical data are presented and validated through extensive simulation, with physical interpretations given, to demonstrate the feasibility of our algorithm design.
Cross-layer Quality of Service Support for UWB Wireless Multimedia Sensor Networks
"... are networks of wirelessly interconnected devices that allow retrieving video and audio streams, still images, and scalar sensor data. WMSN require the sensor network paradigm to be rethought in view of the need for mechanisms to deliver multimedia content with a pre-defined level of quality of serv ..."
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Cited by 14 (6 self)
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are networks of wirelessly interconnected devices that allow retrieving video and audio streams, still images, and scalar sensor data. WMSN require the sensor network paradigm to be rethought in view of the need for mechanisms to deliver multimedia content with a pre-defined level of quality of service (QoS). In this paper, a new cross-layer communication architecture based on the time-hopping impulse radio ultra wide band technology is described, designed to reliably and flexibly deliver QoS to heterogeneous applications in WMSNs, by leveraging and controlling interactions among different layers of the protocol stack according to applications requirements. Simulations show that the proposed system achieves the performance objectives of WMSNs without sacrificing on design modularity. I.
Multipath Routing in Wireless Sensor Networks: Survey and Research Challenges
, 2012
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