1 / 37

Emerging Technologies

CISB422. Emerging Technologies. Sensor Networks. Background. Definition:

wilmet
Télécharger la présentation

Emerging Technologies

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. CISB422 Emerging Technologies Sensor Networks

  2. Background • Definition: • Wiki: consists of spatially distributed autonomoussensors to monitor physical or environmental conditions, such as temperature, sound, pressure, etc. and to cooperatively pass their data through the network to a main location • Key to gathering information needed by smart environments

  3. Fundamental Concepts Sensor An object which performs sensing task

  4. Fundamental Concepts Sensing Technique to gather information about physical object or processes including the occurrences of events

  5. Fundamental Concepts • Sensor • A device that detects a change in a physical stimulus and turns it into a signal which can be measured or recorded • Transducer • A device that transfers power from one system to another in the same of different form

  6. Sensor Technology

  7. Transducers

  8. Sensor classification • Which sensor for which application? • Stimulus, specifications, physical phenomenon, conversion mechanism, material and application • Stimulus • Acoustic, electric, magnetic, optical, thermal, mechanical • Physical property to be monitored • Temperature, chemical, light, humidity, position, motion • Active • Require external power supply • Passive • Detect energy and derive power from the energy input

  9. Sensor classification cont

  10. Wireless Sensor/Actuator Network • Networks of nodes that sense and potentially also control their environment. They communicate the information through wireless links “enabling interaction between people or computers and the surrounding environment” • Verdone et all, 2008

  11. Wireless sensor/actuator network • A collection of small randomly dispersed devices that provide 3 main functions:- • Ability to monitor physical and environmental conditions (real time) • Ability to operate devices that control the conditions • Ability to provide efficient, reliable communications via wireless network

  12. Wireless Sensor/Actuator Networks

  13. History • Defense Advanced Research Projects Agency (DARPA) • 1978: Distributed Sensor Nets Workshop • Early 1980s: • Distributed Sensor Networks (DSN) • Sensor Information Technology (SensIT) program

  14. History-cont • Rockwell Science Center, UCLA • 1996: Low Power Wireless Integrated Microsensor (LWIM) • UC Berkeley • Smart Dust project (motes) • Berkeley Wireless Research Center • Low-power sensor device • MIT • μAMPS project-low power hardware and software components for sensor nodes

  15. Basic of Wireless Sensor Networks • Network Topology • Communication Protocols and Routing • Sensor Node Architecture

  16. Network Topology • Point to Point • Star • Mesh • Extended Star

  17. Routing Protocols • Routing protocols depends on: • Power and resource limitations of the network nodes • Time-varying quality of the wireless channel • Possibility for packet loss and delay • First class: • Flat network architecture: all nodes are peers • Second class • Structured: nodes are organized in clusters based on residual energy • Third class • Data-centric approach to disseminate interest: attribute based naming • Fourth class • Uses location to address a sensor node

  18. Routing Protocols • Low Energy Adaptive Clustering Hierarchy (LEACH) • Clustering-based protocol • Utilizes randomized rotation of the cluster-heads to evenly distribute the energy load among sensor nodes in the network • Assume base station is fixed and far from sensors, all nodes are homogenous and energy-constrained

  19. Routing Protocols cont • Power Efficient Gathering in Sensor Information System (PEGASIS) • Chain-based power efficient protocols based on LEACH • Near optimal • All nodes have location information about all other nodes and each has the capability of transmitting data to base station directly • Sensor nodes are immobile

  20. Routing Protocols cont • Threshold Sensitive Energy Efficient Sensor Network (TEEN) • Cluster based routing protocol • Network is composed of a base station and sensor nodes with the same initial energy • Base station has a constant power supply and can transmit with high power to all the nodes directly

  21. Routing Protocols cont • Flooding and Gossiping • Simple, less maintenance • Each node which receives data sends the packet to its neighbors

  22. Sensor Node Architecture

  23. Wireless Sensor Networks Standards and Specifications • IEEE 1451 • WirelessHart • ZigBee / 802.15.4 • ZigBee IP • 6LoWPAN

  24. Challenges and Constraints • Energy • Self-Management • Wireless Networking • Decentralized Management • Design Constraints • Security • Others

  25. Self Management • Ad Hoc Deployment • No predetermined and engineered locations of individual sensor nodes • Unattended Operation • Operate without human intervention: configuration, adaptation, maintenance, repair must be performed autonomously • Self organization: network’s ability to adapt configuration parameters based on system and environmental state • Self optimization: device’s ability to monitor and optimize the use of its own resources • Self protection: device’s ability to recognize and protect itself from intrusions and attacks • Self healing: device’s ability to discover, identify, react to network disruptions

  26. Wireless Networking • Attenuation: RF signal fades • Larger distance between base station and sensor node requires more transmission power • Must support multi-hop communications and routing

  27. Decentralized Management • Due to large scale and energy constraint • Results are not optimal, but more energy efficient

  28. Security • Sensitive information • Exposed to malicious intrusions and attacks • Wireless:-eavesdrop on sensor transmission • Denial of service attack • Use of jamming attack: high powered wireless signals are used to prevent successful sensor communications

  29. Others

  30. Technology in Focus • Applications: • Air, soil and water monitoring • Condition based maintenance • Habitat monitoring • Seismic detection • Military surveillance • Inventory tracking • Smart spaces

  31. Applications • Structural Health Monitoring • Traffic Control • Health Care • Pipeline monitoring • Precision Agriculture • Active Volcano • Underground Mining • Smart City

  32. Healthcare

  33. Smart Building • Heating, ventilation, and air conditioning systems (HVAC) • Lightning • Shading • Air quality and window control • Systems switching off devices • Metering (covered in the section on smart grids) • Standard household applications (e.g. televisions, washing machines) • Security and safety (access control).

  34. Smart Building: The New York Times

  35. Smart Building: The New York Times cont • Consumes 30% less energy than traditional skycrappers • Has a curtain wall-serves as sunscreen and changes color during the day • Shading system-tracks the sun position and relies on sensor network to automatically actuate the raising and lowering of the shades • HVAC system is equipped with temperature sensors; rely on free air cooling

  36. Smart Building: Type of Sensors • Temperature sensors and heat detectors • Light level detectors • Movement and occupancy sensors • Smoke and gas detectors • Status sensors (e.g. air quality, open windows) • Glass break sensors

  37. Precision Agriculture • Plant/crop monitoring • Soil monitoring • Climate monitoring • Insect-disease-weed monitoring • Example: • Low Frequency Array (LOFAR) Agro Project • Measured micro climate in a potato field to provide information on how to fight fungal disease and phytophra

More Related