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Showing papers on "Wireless sensor network published in 2015"


Journal ArticleDOI
TL;DR: This paper presents an overview of the RF-EHNs including system architecture, RF energy harvesting techniques, and existing applications, and explores various key design issues according to the network types, i.e., single-hop networks, multiantenna networks, relay networks, and cognitive radio networks.
Abstract: Radio frequency (RF) energy transfer and harvesting techniques have recently become alternative methods to power the next-generation wireless networks As this emerging technology enables proactive energy replenishment of wireless devices, it is advantageous in supporting applications with quality-of-service requirements In this paper, we present a comprehensive literature review on the research progresses in wireless networks with RF energy harvesting capability, which is referred to as RF energy harvesting networks (RF-EHNs) First, we present an overview of the RF-EHNs including system architecture, RF energy harvesting techniques, and existing applications Then, we present the background in circuit design as well as the state-of-the-art circuitry implementations and review the communication protocols specially designed for RF-EHNs We also explore various key design issues in the development of RF-EHNs according to the network types, ie, single-hop networks, multiantenna networks, relay networks, and cognitive radio networks Finally, we envision some open research directions

2,352 citations


Journal ArticleDOI
TL;DR: An overview of state-of- the-art RF-enabled WET technologies and their applications to wireless communications, highlighting the key design challenges, solutions, and opportunities ahead.
Abstract: The performance of wireless communication is fundamentally constrained by the limited battery life of wireless devices, the operations of which are frequently disrupted due to the need of manual battery replacement/recharging. The recent advance in RF-enabled wireless energy transfer (WET) technology provides an attractive solution named wireless powered communication (WPC), where the wireless devices are powered by dedicated wireless power transmitters to provide continuous and stable microwave energy over the air. As a key enabling technology for truly perpetual communications, WPC opens up the potential to build a network with larger throughput, higher robustness, and increased flexibility compared to its battery-powered counterpart. However, the combination of wireless energy and information transmissions also raises many new research problems and implementation issues that need to be addressed. In this article, we provide an overview of stateof- the-art RF-enabled WET technologies and their applications to wireless communications, highlighting the key design challenges, solutions, and opportunities ahead.

1,032 citations


Journal ArticleDOI
TL;DR: A smart hospital system (SHS), which relies on different, yet complementary, technologies, specifically RFID, WSN, and smart mobile, interoperating with each other through a Constrained Application Protocol (CoAP)/IPv6 over low-power wireless personal area network (6LoWPAN) network infrastructure.
Abstract: Over the last few years, the convincing forward steps in the development of Internet of Things (IoT)-enabling solutions are spurring the advent of novel and fascinating applications. Among others, mainly radio frequency identification (RFID), wireless sensor network (WSN), and smart mobile technologies are leading this evolutionary trend. In the wake of this tendency, this paper proposes a novel, IoT-aware, smart architecture for automatic monitoring and tracking of patients, personnel, and biomedical devices within hospitals and nursing institutes. Staying true to the IoT vision, we propose a smart hospital system (SHS), which relies on different, yet complementary, technologies, specifically RFID, WSN, and smart mobile, interoperating with each other through a Constrained Application Protocol (CoAP)/IPv6 over low-power wireless personal area network (6LoWPAN)/representational state transfer (REST) network infrastructure. The SHS is able to collect, in real time, both environmental conditions and patients’ physiological parameters via an ultra-low-power hybrid sensing network (HSN) composed of 6LoWPAN nodes integrating UHF RFID functionalities. Sensed data are delivered to a control center where an advanced monitoring application (MA) makes them easily accessible by both local and remote users via a REST web service. The simple proof of concept implemented to validate the proposed SHS has highlighted a number of key capabilities and aspects of novelty, which represent a significant step forward compared to the actual state of the art.

913 citations


Journal ArticleDOI
TL;DR: The existing state-of-the-art in wireless sensor networks for agricultural applications is reviewed thoroughly and various case studies to thoroughly explore the existing solutions proposed in the literature in various categories according to their design and implementation related parameters.

627 citations


Journal ArticleDOI
TL;DR: In this article, the authors reviewed the most updated progress of self-powered active sensors as a response to a stimulation/triggering from the ambient environment, including the four basic working modes of TENGs.

609 citations


Journal ArticleDOI
TL;DR: This article presents an overview of enabling technologies for efficient WEH, analyzes the lifetime of WEH-enabled IoT devices, and briefly study the future trends in the design of efficientWEH systems and research challenges that lie ahead.
Abstract: The Internet of Things (IoT) is an emerging computing concept that describes a structure in which everyday physical objects, each provided with unique identifiers, are connected to the Internet without requiring human interaction. Long-term and self-sustainable operation are key components for realization of such a complex network, and entail energy-aware devices that are potentially capable of harvesting their required energy from ambient sources. Among different energy harvesting methods, such as vibration, light, and thermal energy extraction, wireless energy harvesting (WEH) has proven to be one of the most promising solutions by virtue of its simplicity, ease of implementation, and availability. In this article, we present an overview of enabling technologies for efficient WEH, analyze the lifetime of WEH-enabled IoT devices, and briefly study the future trends in the design of efficient WEH systems and research challenges that lie ahead.

587 citations


Journal ArticleDOI
TL;DR: This paper proposes a harvest-then-cooperate (HTC) protocol, in which the source and relay harvest energy from the AP in the downlink and work cooperatively in the uplink for the source's information transmission.
Abstract: In this paper, we consider a wireless-powered cooperative communication network consisting of one hybrid access-point (AP), one source, and one relay. In contrast to conventional cooperative networks, the source and relay in the considered network have no embedded energy supply. They need to rely on the energy harvested from the signals broadcasted by the AP for their cooperative information transmission. Based on this three-node reference model, we propose a harvest-then-cooperate (HTC) protocol, in which the source and relay harvest energy from the AP in the downlink and work cooperatively in the uplink for the source's information transmission. Considering a delay-limited transmission mode, the approximate closed-form expression for the average throughput of the proposed protocol is derived over Rayleigh fading channels. Subsequently, this analysis is extended to the multi-relay scenario, where the approximate throughput of the HTC protocol with two popular relay selection schemes is derived. The asymptotic analyses for the throughput performance of the considered schemes at high signal-to-noise radio are also provided. All theoretical results are validated by numerical simulations. The impacts of the system parameters, such as time allocation, relay number, and relay position, on the throughput performance are extensively investigated.

429 citations


Journal ArticleDOI
TL;DR: This technical note investigates how an attacker should schedule its Denial-of-Service (DoS) attacks to degrade the system performance.
Abstract: Security of Cyber-Physical Systems (CPS) has gained increasing attention in recent years. Most existing works mainly investigate the system performance given some attacking patterns. In this technical note, we investigate how an attacker should schedule its Denial-of-Service (DoS) attacks to degrade the system performance. Specifically, we consider the scenario where a sensor sends its data to a remote estimator through a wireless channel, while an energy-constrained attacker decides whether to jam the channel at each sampling time. We construct optimal attack schedules to maximize the expected average estimation error at the remote estimator. We also provide the optimal attack schedules when a special intrusion detection system (IDS) at the estimator is given. We further discuss the optimal attack schedules when the sensor has energy constraint. Numerical examples are presented to demonstrate the effectiveness of the proposed optimal attack schedules.

427 citations


Journal ArticleDOI
TL;DR: Practical engineering solutions are focused on which sensor devices are used and what they are used for; and the identification of sensor configurations and network topologies, which identifies their respective motivations and distinguishes their advantages and disadvantages in a comparative review.
Abstract: In recent years, the range of sensing technologies has expanded rapidly, whereas sensor devices have become cheaper. This has led to a rapid expansion in condition monitoring of systems, structures, vehicles, and machinery using sensors. Key factors are the recent advances in networking technologies such as wireless communication and mobile ad hoc networking coupled with the technology to integrate devices. Wireless sensor networks (WSNs) can be used for monitoring the railway infrastructure such as bridges, rail tracks, track beds, and track equipment along with vehicle health monitoring such as chassis, bogies, wheels, and wagons. Condition monitoring reduces human inspection requirements through automated monitoring, reduces maintenance through detecting faults before they escalate, and improves safety and reliability. This is vital for the development, upgrading, and expansion of railway networks. This paper surveys these wireless sensors network technology for monitoring in the railway industry for analyzing systems, structures, vehicles, and machinery. This paper focuses on practical engineering solutions, principally, which sensor devices are used and what they are used for; and the identification of sensor configurations and network topologies. It identifies their respective motivations and distinguishes their advantages and disadvantages in a comparative review.

392 citations


Journal ArticleDOI
TL;DR: In this paper, a wireless sensor network architecture for vegetable greenhouse is proposed in order to achieve scientific cultivation and lower management costs from the aspect of environmental monitoring, according to the analysis of the features of greenhouse environment, a practical and low-cost greenhouse monitoring system is designed based on WSN technology to monitor key environmental parameters such as the temperature, humidity and illumination.

366 citations


Proceedings ArticleDOI
01 Nov 2015
TL;DR: This paper addresses the challenge of bringing TSCH (Time Slotted Channel Hopping MAC) to dynamic networks, focusing on low-power IPv6 and RPL networks, and introduces Orchestra, which allows Orchestra to build non-deterministic networks while exploiting the robustness of TSCH.
Abstract: Time slotted operation is a well-proven approach to achieve highly reliable low-power networking through scheduling and channel hopping. It is, however, difficult to apply time slotting to dynamic networks as envisioned in the Internet of Things. Commonly, these applications do not have pre-defined periodic traffic patterns and nodes can be added or removed dynamically.This paper addresses the challenge of bringing TSCH (Time Slotted Channel Hopping MAC) to such dynamic networks. We focus on low-power IPv6 and RPL networks, and introduce Orchestra. In Orchestra, nodes autonomously compute their own, local schedules. They maintain multiple schedules, each allocated to a particular traffic plane (application, routing, MAC), and updated automatically as the topology evolves. Orchestra (re)computes local schedules without signaling overhead, and does not require any central or distributed scheduler. Instead, it relies on the existing network stack information to maintain the schedules. This scheme allows Orchestra to build non-deterministic networks while exploiting the robustness of TSCH.We demonstrate the practicality of Orchestra and quantify its benefits through extensive evaluation in two testbeds, on two hardware platforms. Orchestra reduces, or even eliminates, network contention. In long running experiments of up to 72~h we show that Orchestra achieves end-to-end delivery ratios of over 99.99%. Compared to RPL in asynchronous low-power listening networks, Orchestra improves reliability by two orders of magnitude, while achieving a similar latency-energy balance.

Proceedings ArticleDOI
24 Aug 2015
TL;DR: SDN-WISE is stateful and pursues two objectives: to reduce the amount of information exchanged between sensor nodes and the SDN network controller, and to make sensor nodes programmable as finite state machines so enabling them to run operations that cannot be supported by stateless solutions.
Abstract: In this paper SDN-WISE, a Software Defined Networking (SDN) solution for WIreless SEnsor networks, is introduced. Differently from the existing SDN solutions for wireless sensor networks, SDN-WISE is stateful and pursues two objectives: (i) to reduce the amount of information exchanged between sensor nodes and the SDN network controller, and (ii) to make sensor nodes programmable as finite state machines so enabling them to run operations that cannot be supported by stateless solutions. A detailed description of SDN-WISE is provided in this paper. SDN-WISE offers APIs that allow software developers to implement the SDN Controller using the programming language they prefer. This represents a major advantage of SDN-WISE as compared to existing solutions because it increases flexibility and simplicity in network programming. A prototype of SDN-WISE has been implemented and is described in this paper. Such implementation contains the modules that allow a real SDN Controller to manage an OMNeT++ simulated network. Finally, the paper illustrates the results obtained through an experimental testbed which has been developed to evaluate the performance of SDN-WISE in several operating conditions.

Journal ArticleDOI
TL;DR: This study presents a first look at the effects of security attacks on the communication channel as well as sensor tampering of a connected vehicle stream equipped to achieve CACC, and shows that an insider attack can cause significant instability in the CACC vehicle stream.
Abstract: Autonomous vehicles capable of navigating unpredictable real-world environments with little human feedback are a reality today. Such systems rely heavily on onboard sensors such as cameras, radar/LIDAR, and GPS as well as capabilities such as 3G/4G connectivity and V2V/V2I communication to make real-time maneuvering decisions. Autonomous vehicle control imposes very strict requirements on the security of the communication channels used by the vehicle to exchange information as well as the control logic that performs complex driving tasks such as adapting vehicle velocity or changing lanes. This study presents a first look at the effects of security attacks on the communication channel as well as sensor tampering of a connected vehicle stream equipped to achieve CACC. Our simulation results show that an insider attack can cause significant instability in the CACC vehicle stream. We also illustrate how different countermeasures, such as downgrading to ACC mode, could potentially be used to improve the security and safety of the connected vehicle streams.

Journal ArticleDOI
TL;DR: This work develops one data collection protocol called EDAL, which stands for Energy-efficient Delay-aware Lifetime-balancing data collection, and proposes both a centralized heuristic to reduce its computational overhead and a distributed heuristics to make the algorithm scalable for large-scale network operations.
Abstract: Our work in this paper stems from our insight that recent research efforts on open vehicle routing (OVR) problems, an active area in operations research, are based on similar assumptions and constraints compared to sensor networks. Therefore, it may be feasible that we could adapt these techniques in such a way that they will provide valuable solutions to certain tricky problems in the wireless sensor network (WSN) domain. To demonstrate that this approach is feasible, we develop one data collection protocol called EDAL, which stands for Energy-efficient Delay-aware Lifetime-balancing data collection. The algorithm design of EDAL leverages one result from OVR to prove that the problem formulation is inherently NP-hard. Therefore, we proposed both a centralized heuristic to reduce its computational overhead and a distributed heuristic to make the algorithm scalable for large-scale network operations. We also develop EDAL to be closely integrated with compressive sensing, an emerging technique that promises considerable reduction in total traffic cost for collecting sensor readings under loose delay bounds. Finally, we systematically evaluate EDAL to compare its performance to related protocols in both simulations and a hardware testbed.

Journal ArticleDOI
TL;DR: A Multi-Level Smart City architecture is proposed based on semantic web technologies and Dempster-Shafer uncertainty theory and described and explained in terms of its functionality and some real-time context-aware scenarios.

Journal ArticleDOI
01 Sep 2015
TL;DR: The document discusses the applicability and limitations of existing IP-based Internet security protocols and other security protocols used in wireless sensor networks, which are potentially suitable in the context of IoT.
Abstract: The Internet of Things or "IoT" defines a highly interconnected network of heterogeneous devices where all kinds of communications seem to be possible, even unauthorized ones. As a result, the security requirement for such network becomes critical whilst common standard Internet security protocols are recognized as unusable in this type of networks, particularly due to some classes of IoT devices with constrained resources. The document discusses the applicability and limitations of existing IP-based Internet security protocols and other security protocols used in wireless sensor networks, which are potentially suitable in the context of IoT. The analysis of these protocols is discussed based on a taxonomy focusing on the key distribution mechanism.

Journal ArticleDOI
TL;DR: A survey on reliability protocols in WSNs is presented and several reliability schemes based on retransmission and redundancy techniques using different combinations of packet or event reliability in terms of recovering the lost data using hop-by-hop or end-to-end mechanisms are reviewed.

Proceedings ArticleDOI
16 Jul 2015
TL;DR: This paper exploits the strategic position of such gateways to offer several higher-level services such as local storage, real-time local data processing, embedded data mining, etc., proposing thus a Smart e-Health Gateway.
Abstract: There have been significant advances in the field of Internet of Things (IoT) recently. At the same time there exists an ever-growing demand for ubiquitous healthcare systems to improve human health and well-being. In most of IoT-based patient monitoring systems, especially at smart homes or hospitals, there exists a bridging point (i.e., gateway) between a sensor network and the Internet which often just performs basic functions such as translating between the protocols used in the Internet and sensor networks. These gateways have beneficial knowledge and constructive control over both the sensor network and the data to be transmitted through the Internet. In this paper, we exploit the strategic position of such gateways to offer several higher-level services such as local storage, real-time local data processing, embedded data mining, etc., proposing thus a Smart e-Health Gateway. By taking responsibility for handling some burdens of the sensor network and a remote healthcare center, a Smart e-Health Gateway can cope with many challenges in ubiquitous healthcare systems such as energy efficiency, scalability, and reliability issues. A successful implementation of Smart e-Health Gateways enables massive deployment of ubiquitous health monitoring systems especially in clinical environments. We also present a case study of a Smart e-Health Gateway called UTGATE where some of the discussed higher-level features have been implemented. Our proof-of-concept design demonstrates an IoT-based health monitoring system with enhanced overall system energy efficiency, performance, interoperability, security, and reliability.

Journal ArticleDOI
04 May 2015-Sensors
TL;DR: The research extends the smart home system to smart buildings and models the design issues related to the smart building environment; these design issues are linked with system performance and reliability.
Abstract: Our research approach is to design and develop reliable, efficient, flexible, economical, real-time and realistic wellness sensor networks for smart home systems. The heterogeneous sensor and actuator nodes based on wireless networking technologies are deployed into the home environment. These nodes generate real-time data related to the object usage and movement inside the home, to forecast the wellness of an individual. Here, wellness stands for how efficiently someone stays fit in the home environment and performs his or her daily routine in order to live a long and healthy life. We initiate the research with the development of the smart home approach and implement it in different home conditions (different houses) to monitor the activity of an inhabitant for wellness detection. Additionally, our research extends the smart home system to smart buildings and models the design issues related to the smart building environment; these design issues are linked with system performance and reliability. This research paper also discusses and illustrates the possible mitigation to handle the ISM band interference and attenuation losses without compromising optimum system performance.

Journal ArticleDOI
TL;DR: The key approach to enable efficient and reliable management of WSN within an infrastructure supporting various WSN applications and services is a cross-layer design of lightweight and cloud-based RESTful Web service.
Abstract: With the accelerated development of Internet-of-Things (IoT), wireless sensor networks (WSNs) are gaining importance in the continued advancement of information and communication technologies, and have been connected and integrated with the Internet in vast industrial applications. However, given the fact that most wireless sensor devices are resource constrained and operate on batteries, the communication overhead and power consumption are therefore important issues for WSNs design. In order to efficiently manage these wireless sensor devices in a unified manner, the industrial authorities should be able to provide a network infrastructure supporting various WSN applications and services that facilitate the management of sensor-equipped real-world entities. This paper presents an overview of industrial ecosystem, technical architecture, industrial device management standards, and our latest research activity in developing a WSN management system. The key approach to enable efficient and reliable management of WSN within such an infrastructure is a cross-layer design of lightweight and cloud-based RESTful Web service.

Journal ArticleDOI
TL;DR: This paper focuses on comprehensively gathering most recent developments in UWSN applications and their deployments, and classified the underwater applications into five main classes, namely, monitoring, disaster, military, navigation, and sports, to cover the large spectrum of UWSN.
Abstract: There is no escaping fact that a huge amount of unexploited resources lies underwater which covers almost 70% of the Earth. Yet, the aquatic world has mainly been unaffected by the recent advances in the area of wireless sensor networks (WSNs) and their pervasive penetration in modern day research and industrial development. The current pace of research in the area of underwater sensor networks (UWSNs) is slow due to the difficulties arising in transferring the state-of-the-art WSNs to their underwater equivalent. Maximum underwater deployments rely on acoustics for enabling communication combined with special sensors having the capacity to take on harsh environment of the oceans. However, sensing and subsequent transmission tend to vary as per different subsea environments; for example, deep sea exploration requires altogether a different approach for communication as compared to shallow water communication. This paper particularly focuses on comprehensively gathering most recent developments in UWSN applications and their deployments. We have classified the underwater applications into five main classes, namely, monitoring, disaster, military, navigation, and sports, to cover the large spectrum of UWSN. The applications are further divided into relevant subclasses. We have also shown the challenges and opportunities faced by recent deployments of UWSN.

Journal ArticleDOI
TL;DR: A robust anonymous authentication protocol for health-care applications using WMSNs is proposed, which has strong security and computational efficiency and is more suitable for Health-Care applications usingWMSNs.
Abstract: With the fast development of wireless communication technologies and semiconductor technologies, the wireless sensor network (WSN) has been widely used in many applications As an application of the WSN, the wireless medical sensor network (WMSN) could improve health-care quality and has become important in the modern medical system In the WMSN, physiological data are collected by sensors deployed in the patient's body and sent to health professionals' mobile devices through wireless communication Then health professionals could get the status of the patient anywhere and anytime The data collected by sensors are very sensitive and important The leakage of them could compromise the patient's privacy and their malicious modification could harm the patient's health Therefore, both security and privacy are two important issues in WMSNs Recently, Kumar et al proposed an efficient authentication protocol for health-care applications using WMSNs and claimed that it could withstand various attacks However, we find that their protocol is vulnerable to the off-line password guessing attack and the privileged insider attack We also point out that their protocol cannot provide user anonymity In this paper, we will propose a robust anonymous authentication protocol for health-care applications using WMSNs Compared with Kumar et al's protocol, the proposed protocol has strong security and computational efficiency Therefore, it is more suitable for health-care applications using WMSNs

Journal ArticleDOI
TL;DR: A survey on potential renewable energy resources along with their characteristics and applications in WSN and various battery recharging techniques and their applications with respect to WSN are presented.
Abstract: In recent years there has been several technological advances in Wireless Sensor Networks (WSN), but energy still remains a paramount resource. The amount of available energy has a direct effect on the performance, functionality and lifetime of WSN. Being bound by cost and size, sensor nodes are usually equipped with limited amount of energy and therefore requires a replacement of batteries occasionally. But replacement might not always be feasible option and in some scenarios might even be prohibitive. This indicates the need for more viable solutions, these involve generating energy at the sensor nodes or have it delivered to them i.e., energy harvesting or wireless energy transfer. The objective of this paper is threefold: first we present a survey on potential renewable energy resources along with their characteristics and applications in WSN. Second, this study also describes various battery recharging techniques and their applications with respect to WSN. Finally, we discuss formidable issues, challenges and future research directions.

Journal ArticleDOI
TL;DR: In this paper, a wireless communication network with a full-duplex hybrid energy and information access point and a set of wireless users with energy harvesting capabilities is considered, where the causal dependence of each user's harvesting time on the transmission time of earlier users is modeled by assuming that energy harvested in the future cannot be used for the current transmission.
Abstract: In this paper, we consider a wireless communication network with a full-duplex hybrid energy and information access point and a set of wireless users with energy harvesting capabilities. The hybrid access point (HAP) implements full-duplex through two antennas: one for broadcasting wireless energy to users in the downlink and the other for simultaneously receiving information from the users via time division multiple access (TDMA) in the uplink. Each user can continuously harvest wireless power from the HAP until it transmits, i.e., the energy causality constraint is modeled by assuming that energy harvested in the future cannot be used for the current transmission. This leads to the causal dependence of each user's harvesting time on the transmission time of earlier users, e.g., the second user scheduled to transmit can harvest more energy if the first user has longer transmission time. Under this setup, we investigate the sum-throughput maximization (STM) problem and the total-time minimization (TTM) problem for the proposed full-duplex wireless-powered communication network. For the STM problem, the optimal solution is obtained as a closed-form expression, which can be computed with linear complexity. For the TTM problem, by exploiting the properties of the coupled constraints, we propose a two-step algorithm to obtain an optimal solution. Then, low-complexity suboptimal solutions are proposed for each problem by exploiting the characteristics of the optimal solutions. Finally, simulation studies on the effect of user scheduling show that different scheduling strategies should be adopted for STM and TTM.

Journal ArticleDOI
TL;DR: This paper adopts a power-law decaying data model verified by real data sets and proposes a random projection-based estimation algorithm for this data model, which requires fewer compressed measurements and greatly reduces the energy consumption.
Abstract: Data collection is a crucial operation in wireless sensor networks. The design of data collection schemes is challengingdue to the limited energy supply and the hot spot problem. Leveraging empirical observations that sensory data possess strongspatiotemporal compressibility, this paper proposes a novel compressive data collection scheme for wireless sensor networks. We adopt a power-law decaying data model verified by real data sets and then propose a random projection-based estimation algorithm for this data model. Our scheme requires fewer compressed measurements, thus greatly reduces the energy consumption. It allowssimple routing strategy without much computation and control overheads, which leads to strong robustness in practical applications. Analytically, we prove that it achieves the optimal estimation error bound. Evaluations on real data sets (from the GreenOrbs, IntelLab and NBDC-CTD projects) show that compared with existing approaches, this new scheme prolongs the network lifetime by $1.5 \times$ to $2 \times$ for estimation error 5-20 percent.

Journal ArticleDOI
TL;DR: C-SPINE, a framework for Collaborative BSNs (CBSNs), is proposed and natively supports multi-sensor data fusion among CBSNs to enable joint data analysis such as filtering, time-dependent data integration and classification.

Journal ArticleDOI
12 Dec 2015-Sensors
TL;DR: This paper classifies the existing works into three categories as Static Sensor Network (SSN), Community Sensor network (CSN) and Vehicle sensor network (VSN) based on the carriers of the sensors.
Abstract: The air quality in urban areas is a major concern in modern cities due to significant impacts of air pollution on public health, global environment, and worldwide economy. Recent studies reveal the importance of micro-level pollution information, including human personal exposure and acute exposure to air pollutants. A real-time system with high spatio-temporal resolution is essential because of the limited data availability and non-scalability of conventional air pollution monitoring systems. Currently, researchers focus on the concept of The Next Generation Air Pollution Monitoring System (TNGAPMS) and have achieved significant breakthroughs by utilizing the advance sensing technologies, MicroElectroMechanical Systems (MEMS) and Wireless Sensor Network (WSN). However, there exist potential problems of these newly proposed systems, namely the lack of 3D data acquisition ability and the flexibility of the sensor network. In this paper, we classify the existing works into three categories as Static Sensor Network (SSN), Community Sensor Network (CSN) and Vehicle Sensor Network (VSN) based on the carriers of the sensors. Comprehensive reviews and comparisons among these three types of sensor networks were also performed. Last but not least, we discuss the limitations of the existing works and conclude the objectives that we want to achieve in future systems.

Journal ArticleDOI
TL;DR: A comprehensive model for the power consumption of wireless sensor nodes is presented, which takes a system-level perspective to account for all energy expenditures: communications, acquisition and processing and results in a new framework for studying and analyzing the energy life-cycles in applications.
Abstract: Low-energy technologies in the Internet of Things (IoTs) era are still unable to provide the reliability needed by the industrial world, particularly in terms of the wireless operation that pervasive deployments demand. While the industrial wireless performance has achieved an acceptable degree in communications, it is no easy task to determine an efficient energy-dimensioning of the device in order to meet the application requirements. This is especially true in the face of the uncertainty inherent in energy harvesting. Thus, it is of utmost importance to model and dimension the energy consumption of the IoT applications at the pre-deployment or pre-production stages, especially when considering critical factors, such as reduced cost, life-time, and available energy. This paper presents a comprehensive model for the power consumption of wireless sensor nodes. The model takes a system-level perspective to account for all energy expenditures: communications, acquisition and processing. Furthermore, it is based only on parameters that can empirically be quantified once the platform (i.e., technology) and the application (i.e., operating conditions) are defined. This results in a new framework for studying and analyzing the energy life-cycles in applications, and it is suitable for determining in advance the specific weight of application parameters, as well as for understanding the tolerance margins and tradeoffs in the system.

Journal ArticleDOI
TL;DR: A new distributed event-triggered communication scheme is proposed to determine whether or not each sensor's current sampled-data should be broadcast and transmitted for filter design, and a co-design algorithm for simultaneously determining the filter parameters and the threshold parameters is developed.

Journal ArticleDOI
TL;DR: A survey of the recent advances in radio resource allocation in CR sensor networks (CRSNs) is presented and an insight into the related issues and challenges is provided, and future research directions are clearly identified.
Abstract: Wireless sensor networks (WSNs) use the unlicensed industrial, scientific, and medical (ISM) band for transmissions. However, with the increasing usage and demand of these networks, the currently available ISM band does not suffice for their transmissions. This spectrum insufficiency problem has been overcome by incorporating the opportunistic spectrum access capability of cognitive radio (CR) into the existing WSN, thus giving birth to CR sensor networks (CRSNs). The sensor nodes in CRSNs depend on power sources that have limited power supply capabilities. Therefore, advanced and intelligent radio resource allocation schemes are very essential to perform dynamic and efficient spectrum allocation among sensor nodes and to optimize the energy consumption of each individual node in the network. Radio resource allocation schemes aim to ensure QoS guarantee, maximize the network lifetime, reduce the internode and internetwork interferences, etc. In this paper, we present a survey of the recent advances in radio resource allocation in CRSNs. Radio resource allocation schemes in CRSNs are classified into three major categories, i.e., centralized, cluster-based, and distributed. The schemes are further divided into several classes on the basis of performance optimization criteria that include energy efficiency, throughput maximization, QoS assurance, interference avoidance, fairness and priority consideration, and hand-off reduction. An insight into the related issues and challenges is provided, and future research directions are clearly identified.