Search results for " Sensor Networks."
showing 10 items of 157 documents
Urban Air Quality Monitoring Using Vehicular Sensor Networks
2014
The quality of air is a major concern in modern cities as pollutants have been demonstrated to have significant impact on human health. Networks of fixed monitoring stations have been deployed in urban areas to provide authorities with data to define and enforce dynamically policies to reduce pollutants, for instance by issuing traffic regulation measures. However, fixed networks require careful placement of monitoring stations to be effective. Moreover, changes in urban arrangement, activities, or regulations may affect considerably the monitoring model, especially when budget constraints prevent from relocating stations or adding new ones to the network. In this chapter we discuss a diffe…
A hybrid storage system for wireless sensor nodes powered with energy harvesting
2019
With the recent development of Internet of Things (IoT) and Wireless Sensor Networks (WSN), research and industry have been increasingly focusing on the opportumty of collecting the energy arising from the environment. The Energy Harvesting provides the possibility to supply devices which are placed out of reach or in hazardous spots, e.g. the Wireless Sensor Nodes. Among the different parts belonging to an Energy Harvesting system, the power management network represents a challenging topic. In this paper a Hybrid Energy Storage System (HESS) usable for a WSN powered with Energy Harvesting, based on a battery-capacitor integration, is presented. The experimental results concerning the asse…
Strategies and Techniques for Powering Wireless Sensor Nodes through Energy Harvesting and Wireless Power Transfer
2019
The continuous development of internet of things (IoT) infrastructure and applications is paving the way for advanced and innovative ideas and solutions, some of which are pushing the limits of state-of-the-art technology. The increasing demand for Wireless Sensor Nodes (WSNs) able to collect and transmit data through wireless communication channels, while often positioned in locations that are difficult to access, is driving research into innovative solutions involving energy harvesting (EH) and wireless power transfer (WPT) to eventually allow battery-free sensor nodes. Due to the pervasiveness of radio frequency (RF) energy, RF EH and WPT are key technologies with the potential to power …
Design of Low-Cost Noise Measurement Sensor Network: Sensor Function Design
2010
In this paper, we report the sensor function design and implementation of a wireless sensor network application for measuring environmental acoustic noise. The system is built on ATmega128 and CC2420 platform. The protocol stack is based on CiNet stack with a global synchronization scheme and supports multi-hop communications. Strict filtering function specified by ITU-R 468 (namely A-weighting) is followed. Both the indoor and outdoor test results were compared with standard sound level meters (CESVA SC-20c and Pulsar94) and showed a less than ±2dB error in both short-term and longterm measurement. Power consumption has been measured that a single AA-type battery can sustain the applicatio…
From vertical to horizontal architecture
2006
Some of the main challenges related to wireless sensor networks implementation are low-quality communication, energy conservation, resource-constrained computation, distributed network management, data processing and the scalability of the protocols. This combination makes the implementation of software a demanding task and encourages to new approaches when thinking of software architecture.In this paper an architecture combining a low protocol stack with a cross-layer management entity is presented. One of the main ideas behind the architecture presented is to make application programming easier and to simplify the protocol stack in such a way that it would suit better for the limited reso…
Towards adaptive localization in wireless sensor networks
2012
It is often useful or even indispensable to know the locations of the nodes in a wireless sensor network (WSN), from both network functionality and applications point of view. A potential yet one of the most challenging method is to utilize received signal strength indicator (RSSI) for distance estimation. Albeit easily adopted, using of RSSI is notorious for imprecise distance estimates which can lead to inaccuracies in location estimates. In this paper, we study RSSI-based localization in WSNs through simulation experiments. We evaluate and compare a hybrid algorithm and its modifications with well-known range-based and range-free localization algorithms. Simulation results indicate that …
An Integrated Architecture for Surveillance and Monitoring in an Archaeological Site
2005
This paper describes an on-going work aimed at designing and deploying a system for the surveillance and monitoring of an archaeological site, namely the "Valley of the Temples" in Agrigento, Italy. Given the relevance of the site from an artistical and historical point of view, it is important to protect the monuments from malicious or simply incautious behavior; however, the vastity of the area to be monitored and the vague definition of its boundaries make it unpractical to provide extensive coverage through traditional sensors or similar devices. We describe the design of an architecture for the surveillance of the site and for the monitoring of the visitors' behavior consisting in an i…
A new Scheme for RPL to handle Mobility in Wireless Sensor Networks
2017
Mobile wireless sensor networks (WSNs) are characterised by dynamic changes in the network topology leading to route breaks and disconnections. The IPv6 routing protocol for low power and lossy networks (RPL), which has become a standard, uses the Trickle timer algorithm to handle changes in the network topology. However, neither RPL nor Trickle timer are well adapted to mobility. This paper investigates the problem of supporting mobility when using RPL. It enhances RPL to fit with sensors' mobility by studying two cases. Firstly, it proposes to modify RPL in order to fit with a dynamic and hybrid topology in the context of medical applications. Secondly, it investigates a more general case…
Power-constrained sensor selection and routing for cooperative detection in cognitive radios
2012
Given a spectrum-sensing network, a set of active nodes jointly aggregate sensed data at a preset frequency-band and simultaneously route this information to an arbitrarily chosen querying node through a power-constrained multi-hop path. Locally, each sensor node is assumed to be an energy-based detector. This work focuses on deriving algorithms that jointly optimize sensor selection and cooperative detection from which a power-efficient route to the querying node can be established, and then, a tree routing structure spanning the chosen nodes is constructed under a power budget constraint. Sensor information is sequentially aggregated along this optimized routing structure up to the queryi…
An intrusion detection system for selective forwarding attack in IPv6-based mobile WSNs
2017
Selective forwarding attack is considered among the most dangerous attack in wireless sensor networks, particularly in mobile environment. The attackers compromise legitimate nodes and selectively drop some packets. In addition to that, the movement of some nodes increases link failures, collisions and packet loss. So, it will be more difficult to detect malicious nodes from legitimates ones. This paper focuses on detecting selective forwarding attackers in IPv6-based mobile wireless sensor networks when the standardized IPv6 Routing Protocol for Low Power and Lossy Networks (RPL) is used. Contrarily to previous works which propose solutions to detect selective forwarding attack in static w…