Solution For Wireless Sensor Networks Research Articles

Evaluation of RPL-compliant routing solutions in real-life WSNs

Wireless Sensor Networks (WSN) applications continue to expand and already cover almost all our daily activities improving from security and environmental efficiency to gaming experience. The diverse applications running on top of WSNs have led to the design of an immense number of routing protocols. Few years ago, the IETF standardized the IPv6 routing protocol for low-power and lossy networks (RPL) which is based on routing metrics to build communication paths between a source and the destination node. While significant efforts have focused on the design of routing metrics that satisfy the various applications, limited work has been reported on validating their performance using real-life motes. In this paper, we focus on validating the simulation results (obtained through the JSim simulator) using TelosB motes for a set of routing metrics that have been proposed in our previous articles.

Energy-efficient mobile targets detection in the presence of mobile sinks

Tracking moving targets has become an increasingly important application for sensor networks. Sensor nodes may sense moving targets far away from the Source, and hence a large amount of energy may be wasted by them to send sensory data to the Source. Designing efficient algorithms and protocols for data dissemination to mobile sinks is an interesting research and engineering issue, especially for large-scale wireless sensor networks (WSNs). Sink mobility brings new challenges to the design of data dissemination. The location updates for each mobile sink need to be continuously propagated through the field to all sensor nodes, so that future data reports can be correctly delivered to the sink. As energy and resources of a sensor node are limited, these algorithms and protocols should meet a high energy efficiency and a high delivery ratio. To deal with this issue, we propose a framework, called Tree Overlay Grid (TOG), for data collection and dissemination. To route queries and deliver data efficiently in our framework, a geometric routing GFB (Greedy Forwarding within Bound) is proposed to create a TTDD-like grid network, and a tree protocol is used to construct local trees around sinks. In addition, two mechanisms are introduced to prolong the network lifetime. The first mechanism tries to save energy by reducing the traffic load; the second one tries to slow down energy consumption by balancing the traffic load. The simulation results show that TOG outperforms the best known data collection solution and some current data collection solutions for WSNs with multiple mobile sinks.

Design and Implement of Zigbee Network System Based on the Transparent Transmission Mode

Currently main short-range communication technologies which are used to build wireless sensor network im- plementations conclude Bluetooth, WIFI technology and ZigBee technology. Zigbee technology has advantages in trans- mission distance, node capacity, battery life, etc. And ZigBee protocol formulates the network layer and application layer standard on the basis of IEEE 802.15.4 physical layer and data link layer standards, ZigBee technology is considered to be the best solution for wireless sensor networks. Wireless sensor network applications based on ZigBee technology mainly takes use of ZigBee protocol to implementnet working and data transmission. In order to simplify the implementation of ZigBee technology, this article put forward a kind of ZigBee Network system based on the transparent transmission mode. The system uses ZigBee firmware module to build the hardware platform, implements the control and functions of ZigBee firmware module through interface RS232 and implements the data transparent transmission inside network.Experimental tests show that: the network has a lower packet loss rate based on ZigBee network transparent transmission mode, reason- able packet length helps to reduce power consumption and improve the system stability, meanwhile extend the life cycle of the system.

A multi-level clustering scheme based on cliques and clusters for wireless sensor networks

Wireless sensor networks (WSNs) have a wide range of applications in our lifetime. Indeed, WSNs perform a various missions and tasks in odor localization, firefighting, medical service, surveillance and security. In order to accomplish these tasks, the sensors have to perform partitioning protocols to form an organization into clusters and cliques. The hierarchical clustering is the key solution for WSNs to deal with the scalability problems in a network composed of millions of nodes. In this paper, a new hierarchical partitioning scheme is presented, named MCCC. It is cliques and clusters based hierarchical scheme that takes into account the size of cliques and clusters, it also minimizes the number of hops between the cluster head and its nodes. The proposed scheme is motivated by the need to have minimum and maximum size for cliques and clusters. This hierarchical scheme is proposed to respond to the energy and memory constraints for WSNs.

Printed flexible thermoelectric generators for use on low levels of waste heat

This work focuses on the design, fabrication and testing of thermoelectric generator (TEG) devices using dispenser printer. A series-parallel prototype of 50 couples, with 3.5mm×600μm×100μm printed element dimensions, is fabricated on a custom designed polyimide substrate. Se doped mechanically alloyed (MA) Bi2Te3 was used as the n-type material whereas Te doped MA Bi0.5Sb1.5Te3 was used as p-type material. The prototype TEG device produces a power output of 33×10−6W at 0.75×10−3A and 43×10−3V for a temperature difference of 20K resulting in a device areal power density of 2.8Wm−2. To achieve a similar power output in a practical situation, such as from pipes carrying hot fluid an experimental study in forced and natural convection is performed. In forced convection, 33×10−6W power output is achieved when the pipe surface temperature is about 373K. While, in natural convection, maximum power up to 8×10−6W power is obtained at 373K pipe surface temperature. Forced convection is desired for the system to generate sufficiently high power. In the case of natural convection, we achieved much lower power compared to forced convection. The prototype presented in this work demonstrates the feasibility of deploying a printable and “perpetual” power solution for practical wireless sensor network (WSN) applications.

Harvested Power Wireless Sensor Network Solution for Disaggregated Current Estimation in Large Buildings

In modern economies, large service buildings are responsible for an important part of the global electrical energy consumption. The implementation of energy saving strategies can benefit from disaggregated consumption monitoring. To tackle this problem, a number of technological solutions exist, being however, expensive in equipment, installation and maintenance. Because of its decentralized operation principle, wireless sensor networks (WSNs) are an important tool to implement disaggregated electrical energy monitoring. The development of a self-powered, battery-free current sensor node for large WSNs may contribute to the implementation of monitoring solutions for large buildings. In this paper, a solution to monitor disaggregated consumption is presented, based on a contact-less power source for Zigbee nodes using a split-core toroidal coil current transformer (SCCT). The proposed device is able to power a battery-free wireless node estimating also the current drawn by the electrical load with a single SCCT. The SCCT is successfully applied to power a battery-free wireless device running a complex communication software stack. The proposed system is described through simulation as well as the experimental results.

A Low Cost, Highly Scalable Wireless Sensor Network Solution to Achieve Smart LED Light Control for Green Buildings

Reducing energy demand in the residential and industrial sectors is an important challenge worldwide. In particular, lights account for a great portion of total energy consumption, and unfortunately a huge amount of this energy is wasted. Light-emitting diode (LED) lights are being used to light offices, houses, industrial, or agricultural facilities more efficiently than traditional lights. Moreover, the light control systems are introduced to current markets, because the installed lighting systems are outdated and energy inefficient. However, due to high costs, installation issues, and difficulty of maintenance; existing light control systems are not successfully applied to home, office, and industrial buildings. This paper proposes a low cost, wireless, easy to install, adaptable, and smart LED lighting system to automatically adjust the light intensity to save energy and maintaining user satisfaction. The system combines motion sensors and light sensors in a low-power wireless solution using Zigbee communication. This paper presents the design and implementation of the proposed system in a real-world deployment. Characterization of a commercial LED panel was performed to evaluate the benefit of dimming for this light technology. Measurements of total power consumption over a continuous six months period (winter to summer) of a busy office were acquired to verify the performance and the power savings across several weather conditions scenarios. The proposed smart lighting system reduces total power consumption in the application scenario by 55% during a six month period and up to 69% in spring months. These figures take also into account individual user preferences.

Sub-sampling framework comparison for low-power data gathering: a comparative analysis.

A key design challenge for successful wireless sensor network (WSN) deployment is a good balance between the collected data resolution and the overall energy consumption. In this paper, we present a WSN solution developed to efficiently satisfy the requirements for long-term monitoring of a historical building. The hardware of the sensor nodes and the network deployment are described and used to collect the data. To improve the network's energy efficiency, we developed and compared two approaches, sharing similar sub-sampling strategies and data reconstruction assumptions: one is based on compressive sensing (CS) and the second is a custom data-driven latent variable-based statistical model (LV). Both approaches take advantage of the multivariate nature of the data collected by a heterogeneous sensor network and reduce the sampling frequency at sub-Nyquist levels. Our comparative analysis highlights the advantages and limitations: signal reconstruction performance is assessed jointly with network-level energy reduction. The performed experiments include detailed performance and energy measurements on the deployed network and explore how the different parameters can affect the overall data accuracy and the energy consumption. The results show how the CS approach achieves better reconstruction accuracy and overall efficiency, with the exception of cases with really aggressive sub-sampling policies.

Experimental study: a LQI-based ranging technique in ZigBee sensor networks

Ranging technology which estimates the distance between two communicating wireless nodes has been widely used as a necessary component in localisation solutions for wireless sensor networks (WSN). Because of low system cost and less computational complexity, link quality indicator (LQI) based ranging techniques are increasingly applied in Zigbee sensor networks. However, due to the environmental affects and electronic noise generated by hardware, raw LQI data could not be directly aligned with distances. To eliminate errors in LQI data and obtain higher ranging accuracy, we design and evaluate a novel LQI-based ranging technique which includes three essential data processing components: pre-correction, error compensation and mixed regression analysis. The proposed ranging technique is implemented and evaluated on a Zigbee sensor prototype - Tarax. Experiment results show that the average ranging error is less than 1 m, confirming that the proposed technique is able to achieve higher ranging accuracy and suitable for localisation applications in WSN.

Scalability of dense wireless lighting control networks

In modern lighting systems, the introduction of wirelessly controlled LED light sources leads to very dense wireless lighting networks. Current approaches for control message transmission are based on broadcasting messages among many luminaires. However, adequate communication performance - in particular, sufficiently low latency and synchronicity - is difficult to ensure in such networks, especially if the network is part of a wireless building management system and carries not only low-latency broadcast messages but also collects data from sensors. This article describes the challenge of dense wireless lighting control networks. In particular, it discusses the underlying mechanisms and refers to current wireless sensor network solutions in which scalability is relevant.

A Survey on Protocols, Platforms and Simulation Tools for Wireless Sensor Networks

Wireless Sensor Networks (WSNs) are becoming very common technology which combine sensing, processing, and wireless multi-hop networking. This paper provides a wide review of the present state about WSNs at the time of its writing. Following a top- down approach, WSNs concept, definition and applications is provided. Furthermore, an overview of WSNs constrains and judgment metrics such as lifetime and latency is given. Then, the communication protocol stack for WSNs is described, and protocols developed for each layer are discussed. Finally, this paper provides review and comparisons of current simulation programs All of these features make the paper valuable for an extensive variety of possible readers, researchers in WSNs, students stating research in WSNs, specialists wanting to offer WSN solutions, and WSN application designers.

Combination Adaptive Traffic Algorithm and Coordinated Sleeping in Wireless Sensor Network

Wireless sensor network (WSN) uses a battery as its primary power source, so that WSN will be limited to battery power for long operations. The WSN should be able to save the energy consumption in order to operate in a long time.WSN has the potential to be the future of wireless communications solutions. WSN are small but has a variety of functions that can help human life. WSN has the wide variety of sensors and can communicate quickly making it easier for people to obtain information accurately and quickly. In this study, we combine adaptive traffic algorithms and coordinated sleeping as power‐efficient WSN solution. We compared the performance of our proposed ideas combination adaptive traffic and coordinated sleeping algorithm with non‐adaptive scheme. From the simulation results, our proposed idea has good‐quality data transmission and more efficient in energy consumption, but it has higher delay than that of non‐adaptive scheme.Keywords:WSN,adaptive traffic,coordinated sleeping,beacon order,superframe order.

Security Analysis in Wireless Sensor Networks

In recent years, wireless sensor network (WSN) is employed in many application areas such as monitoring, tracking, and controlling. For many applications of WSN, security is an important requirement. However, security solutions in WSN differ from traditional networks due to resource limitation and computational constraints. This paper analyzes security solutions: TinySec, IEEE 802.15.4, SPINS, MiniSEC, LSec, LLSP, LISA, and LISP in WSN. The paper also presents characteristics, security requirements, attacks, encryption algorithms, and operation modes. This paper is considered to be useful for security designers in WSNs.

Wireless Environmental Sensor Networking With Analog Scatter Radio and Timer Principles

Environmental variables monitoring with wireless sensor networks (WSNs) is invaluable for precision agriculture applications. However, the effectiveness of existing low-power, conventional (e.g., ZigBee-type) radios in large-scale deployments is limited by power consumption, cost, and complexity constraints, while the existing WSN solutions employing nonconventional, scatter-radio principles have been restricted to communication ranges of up to a few meters. In this paper, the development of a novel analog scatter-radio WSN is presented, that employs semipassive sensor/tags in bistatic topology (i.e., carrier emitter placed in a different location from the reader), consuming <;1 mW of power, with communication range exceeding 100 m. The experimental results indicate that the multipoint surface fitting calibration, in conjunction with the employed two-phase filtering process, both provide a mean absolute error of 1.9% environmental relative humidity for a temperature range of 10 °C-50 °C. In addition, the energy consumption per measurement of the proposed environmental monitoring approach can be lower than that of conventional radio WSNs. Finally, the proposed approach operational characteristics are presented through a real-world network deployment in a tomato greenhouse.

An energy efficient joint localization and synchronization solution for wireless sensor networks using unmanned aerial vehicle

Localization and synchronization are fundamental services for many applications in wireless sensor networks (WSNs), since it is often required to know the sensor nodes' position and global time to relate a given event detection to a specific location and time. However, the localization and synchronization tasks are often performed after the sensor nodes' deployment on the sensor field. Since manual configuration of sensor nodes is usually an impractical activity, it is necessary to rely on specific algorithms to solve both localization and clock synchronization problems of sensor nodes. With this in mind, in this work we propose a joint solution for the problem of 3D localization and time synchronization in WSNs using an unmanned aerial vehicle (UAV). A UAV equipped with GPS flies over the sensor field broadcasting its geographical position. Therefore, sensor nodes are able to estimate their geographical position and global time without the need of equipping them with a GPS device. Through simulation experiments, we show that our proposed joint solution reduces time synchronization and localization errors as well as energy consumption when compared to solutions found in the literature.

K-Coverage Problems and Solutions in Wireless Sensor Networks: A Survey

Wireless Sensor Networks (WSNs) consist of sensor nodes those are capable of sensing environmental data such as temperature, humidity, pressure, sound etc. and transmit those data to a basestation through the network. Achieving sufficient coverage in the sensing area is a challenging feature in WSNs. Coverage indicates that how well an area is monitored i.e., whether each location of an area is within the sensing range of sensors. Some WSNs applications require multilevel coverage where each location in an area is covered by more than one sensor node. Moreover, sensor nodes must have to maintain a communication range among themselves. In this paper, a survey has been presented onk-coverage problems in WSNs where each location of an area should be covered by at least k sensors. Here, two categories of k-coverage problems have been identified and their different solution approaches have been discussed.

Improvement of range-free localization technology by a novel DV-hop protocol in wireless sensor networks

Localization is a fundamental issue for many applications in wireless sensor networks. Without the need of additional ranging devices, the range-free localization technology is a cost-effective solution for low-cost indoor and outdoor wireless sensor networks. Among range-free algorithms, DV-hop (Distance Vector-hop) has the advantage to localize the mobile nodes which has less than three neighbour anchors. Based on the original DV-hop algorithm, this paper presents two improved algorithms (Checkout DV-hop and Selective 3-Anchor DV-hop). Checkout DV-hop algorithm estimates the mobile node position by using the nearest anchor, while Selective 3-Anchor DV-hop algorithm chooses the best 3 anchors to improve localization accuracy. Then, in order to implement these DV-hop based algorithms in network scenarios, a novel DV-hop localization protocol is proposed. This new protocol is presented in detail in this paper, including the format of data payloads, the improved collision reduction method E-CSMA/CA, as well as parameters used in deciding the end of each DV-hop step. Finally, using our localization protocol, we investigate the performance of typical DV-hop based algorithms in terms of localization accuracy, mobility, synchronization and overhead. Simulation results prove that Selective 3-Anchor DV-hop algorithm offers the best performance compared to Checkout DV-hop and the original DV-hop algorithm.

The Research of Wireless Sensor Network System Based on Internet of Things

Along with the once again leap development of science and technology, wireless sensor network technology by a great number of agency predicted to be the core technology of power to change the world, has become the one of the important research field both at home and abroad, has wide application background. It is in special scenario application especially, due to the special restrictions on target area, making the advantages of wireless sensor network system well. In this article, through the research of wireless sensor network system, key technologies and difficulties in the design of the Internet of things system for wireless sensor network solution, and describes in detail the system each function module in detail.

Experimental evaluations of RSS threshold‐based optimised DV‐HOP localisation for wireless ad‐hoc networks

DV-HOP is a well-known connectivity-based range-free scheme which offers a cost-effective localisation solution for resource-constrained wireless ad-hoc and sensor networks. However, it generates a prominent amount of error with small-scale networks due to its multi-hop nature. To minimise the error and to make it applicable to both small- and large-scale networks, it is proposed to configure the connectivity of the network using available received signal strength (RSS) measurements and a predefined RSS threshold. An approximate formula for the optimal RSS threshold value that shows the minimum amount of error for a particular network to be localised is derived as a function of the total number of nodes and the network size. Experimental results confirm that utilising the proposed RSS threshold-based connectivity configuration significantly improves the localisation accuracy of DV-HOP in a practical environment without any extra hardware.

Applied Technology for Typical Attacks and Security Mechanisms in Wireless Sensor Networks

Wireless Sensor Networks (WSNs) are used in many applications in military and commercial areas. These applications often include the monitoring of sensitive information such as enemy movement on the battlefield or the location of personnel in a building. However, due to the highly resource constrained in sensor nodes, traditional security strategies always can do few with attacks on WSNs. In this Paper, we proposes a study of attacks and security mechanisms in WSNs. First, we summarize the attacks to WSNs and the security requirements based on the TCP\IP networking model, then we present the security solutions to each attack. Along the way we highlight the advantages and disadvantages of various WSN solutions and further compare and evaluate these solutions.