1. Wireless Sensor Networks
Rob Roosendaal, Lecturer
INHolland University

2. Agenda Introduction Theoretical Background Practical Information
Agenda
Introduction
Theoretical Background
Practical Information
Wrap up and questions

3. Introduction to Wireless Sensor Networks
Introduction to Wireless Sensor Networks

4. Our projects Alzheimer's disease ADL: Activities in Daily Life
Our projects
Alzheimer's disease
ADL: Activities in Daily Life
Acceptance of technologies
How to measure progress in ADL
Tablet as interface for easy acceptance
Sensor technology for detection
Sensor communication
Collecting data

5. Crawling the web Alzheimer's disease Human computer interaction
Crawling the web
Alzheimer's disease
Human computer interaction
Programming Android tablets
Connectiong devices to a tablet
Wireless Sensor Networks

6. Alzheimer's disease Memory loss that disrupts daily life
Alzheimer's disease
Memory loss that disrupts daily life
Challenges in planning or solving problems
Difficulty completing familiar tasks at home to work or at leisure
Confusion with time or place
Trouble understanding visual images and special relationships
New problems with words in speaking or writing
Misplacing things and loosing the ability to retrace steps
Decreased and poor judgement
Withdrawl from work or social activities
Change in mood and peronality

7. Framework for Disseminating Data
Framework for Disseminating Data
Establish communications message (What should be said?)
Define the audience (To whom should it be said?)
Select the channel (Through what communication medium?)
Market the message (How should the message be stated?)
Evaluate the impact (What effect did the message create?)
Principles and Practice of Public Health Surveillance (Teutsch and Churchill, 2000)

8. Wireless Sensor Network
Wireless Sensor Network
A wireless sensor network (WSN) of spatially distributed autonomous sensors to monitor physical or environmental conditions and to cooperatively pass their data through the network to a main location. The more modern networks are bi-directional, also enabling control of sensor activity.

9. Measuring physical parameters
Measuring physical parameters
Acoustic, sound, vibration
Automotive, transportation
Chemical
Electric current, electric potential, magnetic, radio
Environment, weather, moisture, humidity
Flow, fluid velocity
Ionizing radiation, subatomic particles
Navigation instruments
Position, angle, displacement, distance, speed, acceleration
Optical, light, imaging, photon
Pressure
Force, density, level
Thermal, heat, temperature
Proximity, presence
Sensor technology
Other sensors and sensor related properties and concepts
This is only a summarized list, the complete list of sensors you can use is about 400 items long !

10. Measuring physical parameters
Measuring physical parameters
Focusing on healthcare, domotics and personal environment
Which sensors do we have?

11. IT Points of interest Autonomous sensors
Points of interest IT
Autonomous sensors
Physical or environmental conditions
Cooperatively pass their data
Through the network to a main location
(Bi-directional, control of sensor activity)

12. Autonomous sensors Sensing + Processing + Communication
Autonomous sensors
Sensing + Processing + Communication
Prone to failure
Energy drain
Resource limitations:
Memory, Power, Processing
Sensor network architectures:
Layered, Clustered

13. Physical or environmental conditions
Physical or environmental conditions

14. Cooperatively pass their data
Cooperatively pass their data
Receive or transmit
Transmit if data has to be sent
Single-hop
Close by
Lower transmission rate
Multi-hop
Higher transmission rate
Less nodes available
Data-gathering wireless sensor networks: organization and capacity,
Enrique J. Duarte-Melo, Mingyan Liu

15. Through the network to a main location
Through the network to a main location
Wireless and wired network parts
Distributed routing, different routing protocols
Adapting to changes in connectivity
Real-time communication, connection oriented!
Quality of Service
Security

16. Structure/Backbone (HW)
Structure/Backbone (HW)
Hardware aspects
basic aspects (CPU, memory, radio)
specific sensors aspects (what type of signals are you measuring?)

17. Structure/Backbone (SW)
Structure/Backbone (SW)
Software aspects
Operating system
Network stack aspects
MAC layer aspects
Network layer aspects
Transport layer aspects
Application aspects

18.
Structure/Backbone

19. Equipment Tablet, running the app Static computer for developing
Equipment
Tablet, running the app
Static computer for developing
Wireless sensor network to gather data and sent data to the tablet
Wireless network for the tablet to comunicate with the internet
Server for monitoring the app (compressed data)

20. Wireless Sensor Node (1)
Wireless Sensor Node (1)
Sensor nodes
sensor technology
tiny battery driven computers
wireless communication interface
organize into a network
monitoring of processes, environmental conditions, events
act as routers
forward data cooperatively

21. Wireless Sensor Node (2)
Wireless Sensor Node (2) 4 1 3 5 2

22. Wireless Sensor Node (3)
Wireless Sensor Node (3)
1/5 6 7

23. Classifications of sensor network protocols
Classifications of sensor network protocols

24. Clustered sensor network architecture
Clustered sensor network architecture
Organizes the sensor nodes into clusters
Each cluster is governed by a cluster-head
Only heads send messages to a BS
Suitable for data fusion
Self-organizing

25. Layered sensor network architecture
Layered sensor network architecture
Short-distance, low power
Unified Network Protocol Framework (UNPF)
Integrates three operations:
Network Initialization & Maintenance Protocol
MAC Protocol
Routing Protocol

26. Network Initialization & Maintenance Protocol
Network Initialization & Maintenance Protocol
Base Station (BS) broadcasts ID using Code Division Multiple Access (CDMA) common control channel (BS reaches all nodes in one hop)
Nodes record BS ID & send beacon signal with their own IDs at their low default power levels
All nodes the BS can hear are at 1-hop distance
The BS broadcasts a control packet with all layer one node IDs
All nodes send a beacon signal again
The layer one nodes record the IDs they hear-layer 2
The layer one nodes inform the BS of the layer 2
The BS broadcasts the layer2 nodes IDs,…
To maintain: periodic beaconing updates are required

27.
Routing Protocol
Downlink from the BS is by direct broadcast on the control channel
Enables multi-hop data forwarding to the BS
The remaining energy is considered when forwarding to the next hop (layer)
Only the nodes of the next layer need to be maintained in the routing table

28. Low-Energy Adaptive Clustering Hierarchy (LEACH)
Low-Energy Adaptive Clustering Hierarchy (LEACH)
Self-organizing and adaptive clustering protocol
Evenly distributes the energy expenditure among the sensors
Performs data aggregation where cluster heads act as aggregation points
Two main phases:
Setup phase: organizing the clusters
Steady-state phase: deals with the actual data transfers to the BS

29. Low-Energy Adaptive Clustering Hierarchy (LEACH)
Low-Energy Adaptive Clustering Hierarchy (LEACH)
Merits:
Accounting for adaptive clusters and rotating cluster heads
Opportunity to implement any aggregation function at the cluster heads
Demerits:
Highly dynamic environments
Continuous updates
Mobility

30. Efficient Data Gathering in WSN
Efficient Data Gathering in WSN
Data gathering from different correlated
cues from the network state uses hints or cues about the physical environment to optimize network behavior
energy-efficient rooted aggregation trees a simple, scalable and distributed correlation-aware aggregation structure
congestion reduction techniques providing congestion control from the sink to the sensors in a sensor field

31. Medium Access Control Framing Medium Access Reliability Flow Control
Medium Access Control
Framing
Frame format and data en- and decapsulation
Medium Access
Which devices participate in communication at what time
Reliability
Successful transmission between devices
Flow Control
Prevent frame loss through buffer overloads
Error Control
Error detection or correction

32. Location discovery? Distance estimation Position computation
Location discovery?
Distance estimation
Techniques to estimate the relative distance between nodes
Position computation
Calculate coordinates based on known other nodes
Triangulation, multilateration, proximity
Localization
Based on information about distances and positions

33. Leftovers Quality of network coverage Security Real time communication
Leftovers
Quality of network coverage
Security
Real time communication
...

34.
Conclusion

35. The internet of things is close!
The internet of things is close!
What we can do:
Acquired data
Reports or alarm notices
Automatically forwarded to information systems

36. The internet of things is close!
The internet of things is close!
What we can do with this technology:
Extending the internet into the real-world
Autonomous Information Systems
Automatically update themselves
Synchronize with the actual state of monitored structure or process

37. The internet of things is close!
The internet of things is close!
What we can do with this technology:
Near-real-time information enables early intervention
Prevent abnormal behavior
Malfunction
Damages
Dangerous situations

38. The internet of things is close!
The internet of things is close!
Typical application domains:
Home care and e-health (or t-health)
Environmental monitoring
Factory automation and maintenance
Supply chain and asset management
Physical security and control …

39. Practical Information
Practical Information

40. Wireless Sensor Network
Wireless Sensor Network
Coalesenses
Wireless Sensor Technology
Wireless Sensor Modules
Wireless Sensor Solutions
Solar Power Harvesting
Wireless Sensor Devices
...

41. Wireless Sensor Modules
Wireless Sensor Modules
The iSense modular hardware and software platform for wireless networks for industry and research applications comprises modules for wireless networking, sensors modules, different power supplies, solar power harvesting, interfaces to PCs, GPS and more.

42. Wireless Sensor Solutions
Wireless Sensor Solutions
Based upon a broad range of hardware, software and protocol components as well as our different networking devices, coalesenses offers both standardized as well as customer specific wireless sensor networking systems.

43. Solar Power Harvesting
Solar Power Harvesting
The iSense Solar Power Harvesting System is an out-of-the-box solution for running self-powered wireless sensor networks. By harvesting solar energy and storing it in a rechargeable battery, it allows to operate sensor nodes all-time autonomously

44. Wireless Sensor Devices
Wireless Sensor Devices
coalesenses offers a number of different devices as building blocks for wireless systems, ranging from LAN gateways over repeaters to USB sticks.

45. Wireless Sensor Technology
Wireless Sensor Technology
coalesenses offers a collection of hardware and software for wireless sensor networks, a technology for literally giving eyes and ears to modern control and information systems.

46.
Wrapup and Questions

47. Wrap up Environment: Main question: Health, Alzheimers
Wrap up
Environment:
Health, Alzheimers
Domotics, Wireless Sensor Networks
IT, Tablet and internet connection
Main question:
How can we add value to the life of a patient with Alzheimers

48.
What is next?

49.
Questions