Wide Area Sensor Networks Research Articles

Application and performance of a Low Power Wide Area Sensor Network for distributed remote hydrological measurements

Communication distances of wireless sensor networks (WSNs) are greatly limited in settings where vegetation coverage is moderate or dense, and power consumption can be an issue in remote environmental settings. A newer innovative technology called “Low Power Wide Area Sensor Networks” (LPWAN) is capable of greater communication distances while consuming less power than traditional WSNs. This research evaluates the design and in-field performance of a LPWAN configuration in headwater catchments to measure environmental variables. The performance of the Beta LPWAN deployment indicate reduced signal strength in topographic valleys, but better actual than modelled data transmission performance. System performance during extreme cold temperatures (below – 15 ºC) resulted in increased sensor down time. The configuration of antennae combinations provides the greatest improvement in signal strength and system performance. This technology facilitates remote collection of physically-based, spatially-distributed information within regions with limited accessibility, ultimately advancing data collection capabilities into areas that are not feasible to visit regularly.

Applying AES algorithm for secure data transmission between Sensor node and LoRa Gateway to Web Server

Lora Gateway is an intermediary device that can connect devices in the IoT system. IoT is the Internet of Things, consisting of a system of interrelated digital and mechanical devices and machines, capable of transmitting data over a network without requiring human-computer interaction. Lora is a long distance wireless communication technology that enables communication over a wide range between devices. Through this device, the Sensor nodes in the IoT system can transmit and receive data by LoRa waves to the Gateway and by Wifi/3G to the web server via the Internet. Data communicates in the internet environment, so important information needs to be protected by data encryption. This paper presents research and application of 128-bit AES symmetric encryption algorithm in LoRa wide area sensor network to secure data transmission between IoT devices and web server through LoRa Gateway device. The research team has designed and built models for testing sensor stations with integrated humidity and temperature sensors, LoRa Gateway integrating Lora module and wifi/3G module, developing the interface on web server with decoding, monitoring, and data storage features, and proposing a solution with AES encryption algorithm and architecture applied in the development of embedded software for LoRa module. The research results are tested on the model to test the encryption, data transmission, and decryption functions in applications for IoT LoRa Gateway systems. With this initial research, it is possible to apply the AES algorithm to secure data transmission in IoT Gateway systems.

Human Cognitive Models for Heritage Site Monitoring

Integrating evidence from a single sensor over time is becoming more common due to the Internet of Things (IoT). It can play a critical role in Heritage site monitoring, as networks of sensors are required to catalog and analyze data over extended periods of time. Researchers have often adopted the mechanisms used for multi-source integration, such as Bayesian conditioning and Dempster- Shafer reasoning. Research in human cognitive models provides an interesting alternative insights for accumulating evidence over time. We used this research as a foundation for the current approach which integrates the set theoretic nature of Dempster-Shafer theory with an estimation structure based on Kalman filtering. It is well suited for applications to Wide-area Sensor Networks (WSN) that are commonly found in heritage sites.

CONSTRUCTION OF LORA DATA POWER SENSOR FROM GIOT AND ACSIP USING SQL TECHNIQUE

LoRa is one of developing data commuication infrastructures which can be enabled sensors on a large scale, wide area operations, and low energy consumption.the benefit of Low energy consumption in LoRa impacted on the length of data, the spread factor and the type of operation. by the challanges in smart building, LoRa can be best solution to cover wide area sensor network. and one of the critical points is how to ensure the data can be trusted. The purpose of this research is to observe the data taken from the power used in single phase electrical in residential consumers. the LoRa infrastructure used to deliver the data is using GioT and Acsip as the gateway and End Node, then involving SQL technique as a programming tools to refine the data.

Sub-GHz Band Communication Bridge Connecting TCP/IP Network

Recently, low power wide area (LPWA) communication devices have attracted attention in the construction of wide area sensor networks. A type of LPWA device called a sub-GHz band communication device allows a 1-hop wide area communication system to have improved power consumption. However, a sub-GHz band communication system is not scalable due to the lack of compatibility with heterogeneous communication devices, such as WiFi and LTE. In this paper, we propose a sub-GHz band communication bridge that builds a cross-over communication system connecting a conventional TCP/IP network and LPWA network. The communication bridge enables scalable TCP/IP network services (e.g., HTTP) by transmitting an ethernet frame over an LPWA network. Through experiments using IM920, a dedicated device for 920 MHz band communication, we evaluated the performance and behavior of communication through TCP applications over a TCP/IP network and LPWA network connected by the proposed communication bridge.

Optimized Gateway Placement for Interference Cancellation in Transmit-Only LPWA Networks.

We study the placement of gateways in a low-power wide-area sensor network, when the gateways perform interference cancellation and when the model of the residual error of interference cancellation is proportional to the power of the packet being canceled. For the case of two sensor nodes sending packets that collide, by which we mean overlap in time, we deduce a symmetric two-crescent region wherein a gateway can decode both collided packets. For a large network of many sensors and multiple gateways, we propose two greedy algorithms to optimize the locations of the gateways. Simulation results show that the gateway placements by our algorithms achieve lower average contention, which means higher packet delivery ratio in the same conditions, than when gateways are naively placed, for several area distributions of sensors.

Telecommunication Platforms for Transmitting Sensor Data over Communication Networks-State of the Art and Challenges.

The importance of constructing wide-area sensor networks for holistic environmental state evaluation has been demonstrated. A general structure of such a network has been presented with distinction of three segments: local (based on ZigBee, Ethernet and ModBus techniques), core (base on cellular technologies) and the storage/application. The implementation of these techniques requires knowledge of their technical limitations and electromagnetic compatibility issues. The former refer to ZigBee performance degradation in multi-hop transmission, whereas the latter are associated with the common electromagnetic spectrum sharing with other existing technologies or with undesired radiated emissions generated by the radio modules of the sensor network. In many cases, it is also necessary to provide a measurement station with autonomous energy source, such as solar. As stems from measurements of the energetic efficiency of these sources, one should apply them with care and perform detailed power budget since their real performance may turn out to be far from expected. This, in turn, may negatively affect—in particular—the operation of chemical sensors implemented in the network as they often require additional heating.

Hardware platform for wide-area vehicular sensor networks with mobile nodes

In recent years, Wireless Sensor Networks have experienced significant growth, mainly motivated by the development of standard communication protocols and the availability of low cost microcontrollers and wireless transceivers, resulting in low-power small-size sensing and data processing capable devices, and wireless communication links. In this paper, a hardware platform for the deployment of a heterogeneous multi-tiered Sensor Network architecture supporting highly mobile nodes covering wide geographic areas for automotive applications is proposed. In the presented network architecture, the low level system consists of an IEEE 802.15.4 based Wireless Sensor Network fully composed of compatible devices that support all the standard functionalities. As a novelty, some extensions are proposed to release part of the topological restrictions of IEEE 802.15.4 communication protocol which limit the development of WSN for applications with wide area coverage and high mobility requirements. The proposed hardware platform has been implemented and experimentally validated and characterized in vehicular applications to monitor and communicate specific environmental parameters in a heavy transport fleet.

Statistical Analysis of Array Gain for Cooperative MISO Transmitters without CSI

Virtual Multiple-Input Single-Output (MISO) is recently proposed to extend the benefits of transmitter space diversity to networks in which the deployment of antenna arrays on individual nodes is infeasible from a practical point of view. Ad-hoc and sensor networks are examples of these type of networks. In these scenarios, nodes equipped with single antenna can cooperatively transmit to emulate an antenna array. However, cooperative transmissions require knowledge of the channel state either at the transmitter side or the receiver side in order to achieve full performance gains. Several solutions are proposed in the literature under these assumptions, but at the expense of increased overhead and energy consumption. In this paper, the array gain at the receiver from the non-coherent combining of the signals from multiple transmitters is analyzed in statistical sense, under the assumption that the channel knowledge is unavailable. The transmitters are assumed to be randomly spread over a circular region. More specifically, exact or very accurate closed-form expressions for the expectation and variance of the array gain are obtained, and then a complete statistical distribution is postulated and validated by means of heuristic procedures, goodness-of-fit tests and specialized software. The results obtained in this paper can be especially useful for the implementation of two-tiered wide area sensor networks.

Vibration spectrum analyzer using stretched membranes of polymer piezoelectrics for sensor networks

The key problem tackled in this paper is the development of a stand-alone self-powered sensor to directly sense the spectrum of mechanical vibrations. Such a sensor could be deployed in wide area sensor networks to monitor structural vibrations of large machines (e.g. aircrafts) and initiate corrective action if the structure approaches resonance. In this paper, we study the feasibility of using stretched membranes of polymer piezoelectric polyvinlidene fluoride for low-frequency vibration spectrum sensing. We design and evaluate a low-frequency vibration spectrum sensor that accepts an incoming vibration and directly provides the spectrum of the vibration as the output.

Multi-technological Transmission Platform for a Wide-area Sensor Network

The article presents an idea of building a wide-area sensor network for monitoring the environmental state. The network combines different technologies for data acquisition and is heterogenic in that it is suited to use different data transmission technologies. A distinguishing feature, making this network different from its existing counterparts, is its easy expansion by adding new sensor types, as well as its scalability and functional universality. DOI: http://dx.doi.org/10.5755/j01.eee.19.1.3265

Dynamic Data Driven Applications System Concept for Information Fusion

We present a framework of Information Fusion (IF) using the Dynamic Data Driven Applications Systems (DDDAS) concept. Existing literature at the intersection of these two topics supports environmental modeling (e.g., terrain understanding) for context enhanced applications. Taking advantage of sensor models, statistical methods, and situation- specific spatio-temporal fusion products derived from wide area sensor networks, DDDAS demonstrates robust multi-scale and multi-resolution geographical terrain computations. We highlight the complementary nature of these seemingly parallel approaches and propose a more integrated analytical framework in the context of a cooperative multimodal sensing application. In particular, we use a Wide-Area Motion Imagery (WAMI) application to draw parallels and contrasts between IF and DDDAS systems that warrants an integrated perspective. This elementary work is aimed at triggering a sequence of deeper insightful research towards exploiting sparsely sampled piecewise dense WAMI measurements – an application where the challenges of big-data with regards to mathematical fusion relationships and high-performance computations remain significant and will persist. Dynamic data-driven adaptive computations are required to effectively handle the challenges with exponentially increasing data volume for advanced information fusion systems solutions such as simultaneous target tracking and identification.

Practical Remarks on Designing a Local Segment in a Wide-area Wireless Sensor Network for Measuring Factors Hazardous to the Environment

In order to construct an effective wide-area sensor network, an optimal solution consists in dividing it into a local and a core segment. On the local side, the ZigBee technology is commonly applied to transfer sensor data as it offers effective mechanisms of self-organization and automatic reorganization in case of failure. Since ZigBee is claimed to be natively suited to multi-hop transmission, its performance – in terms of throughput and delay – was quantitatively tested in a chain topology consisting of up to five hops. The achievable data rates were found to be exponentially decreasing with successive hops whereas the delay was growing linearly. A strong dependence was also confirmed between an antenna type used on ZigBee devices and the maximum achievable operating range.DOI: http://dx.doi.org/10.5755/j01.eee.18.9.2821

Efficient and scalable continuous skyline monitoring in two-tier streaming settings

Two-tier streaming settings are a typical dynamic environment where continuous skylines represent an important semantic indicator for multiple attributes. To monitor skylines over the dynamic data in such settings, one needs to continuously update the skyline query results in order to reflect the new data values. This paper tackles the problem of continuous skyline monitoring on a central query server over dynamic data from multiple data sites. Simply sending the updates of tuple values to the server is cost-prohibitive. Therefore, we propose an approach that allows the central server to collaborate with the data sites to monitor the possible skyline changes. By doing so, the processing load is distributed over all the data sites instead of only on the central server. Furthermore, this collaborative approach minimizes the bandwidth consumption between the server and the data sites, which is often critical in a widely distributed environment such as a wide-area sensor network. We give theoretical upper bounds for the computation costs and communication costs of the proposed collaborative approach. We also conduct extensive experiments on both synthetic and real data sets. The experimental results demonstrate that our collaborative approach is efficient, scalable and well-balanced in terms of communication costs and computation costs.

Energy Efficient Topology Control based on Sociological Cluster in Wireless Sensor Networks

The network topology for a wide area sensor network has to support connectivity and a prolonged lifetime for the many applications used within it. The concepts of structure and group in sociology are similar to the concept of cluster in wireless sensor networks. The clustering method is one of the preferred ways to produce a topology for reduced electrical energy consumption. We herein propose a cluster topology method based on sociological structures and concepts. The proposed sociological clustering topology (SOCT) is a method that forms a network in two phases. The first phase, which from a sociological perspective is similar to forming a state within a nation, involves using nodes with large transmission capacity to set up the global area for the cluster. The second phase, which is similar to forming a city inside the state, involves using nodes with small transmission capacity to create regional clusters inside the global cluster to provide connectivity within the network. The experimental results show that the proposed method outperforms other methods in terms of energy efficiency and network lifetime.

A Wide-Area Sensor Network Based on Fiber Optic Power Supply

A Wide-Area Sensor Network Based on Fiber Optic Power Supply

A Wide-Area Sensor Network Based on Fiber Optic Power Supply

A wide-area sensor network whose sensor nodes are driven by supplied laser power is proposed in this paper. Each sensor node produces an optical signal by modulating a part of the supplied laser light and sends it back to a monitor. A developed sensor node was driven with an incident optical power of 1.7 mW, which is low enough to drive more than 100 sensor nodes placed along an optical fiber line. We also developed wireless/optical interface nodes that integrate the sensor network with wireless sensors and realize ubiquitous sensing.

UTupleSpace: A Bi-Directional Shared Data Space for Wide-Area Sensor Network

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The COMPASS-2 satellite and the ground-based LOIS vector sensing radar facility as novel tools for ionospheric plasma diagnostics

To give a more detailed and complete understanding of physical plasma processes that govern the solar–terrestrial space, and to develop qualitative and quantitative models of the magnetosphere–ionosphere–thermosphere coupling, it is necessary to design and build the next generation of instruments for space diagnostics and monitoring. Novel ground-based wide-area sensor networks, such as the LOFAR Outrigger In Scandinavia (LOIS, LOFAR: Low Frequency Array) radar facility, comprising wide band, and vector-sensing radio receivers with full three-dimensional polarization coverage, and multi-spacecraft plasma diagnostics should help solve outstanding problems of space physics and describe long-term environmental changes. The new digital radio frequency analyzer (RFA) on board the low-orbiting COMPASS-2 satellite was designed to monitor and investigate the ionospheric plasma properties. This two-point ground-based and topside ionosphere-located space plasma diagnostic can be a useful new tool for monitoring and diagnosing turbulent plasma properties. The RFA on board the COMPASS-2 satellite is the first in a series of experiments which is planned to be launched into the near-Earth environment. The main purpose of this presentation is to describe new advanced diagnostic techniques of the near-Earth space plasma and point out the scientific challenges of the COMPASS-2 and LOIS experiments.