1. 1 Thomas Watteyne @ EDERC 2010 1. Introduction to Sensor Networks

2. 2 Section 1 - Overview 1. Introduction to Sensor Networks 1.1From Smart Dust to Smart Plants 1.2Applications 1.3The Nature of Wireless 1.4Conclusions Thomas Watteyne @ EDERC 2010

3. 3 1.1 From Smart Dust to Smart Plants

4. 4 The Promise of Wireless time $ sensing computation communication Thomas Watteyne @ EDERC 2010

5. 5 1997, the Smart Dust vision Thomas Watteyne @ EDERC 2010

6. 6 Off-the-Shelf Hardware Thomas Watteyne @ EDERC 2010

7. 7 1999, Optical Communication 15km Thomas Watteyne @ EDERC 2010

8. 8 2001, Intel Developers Forum 800 motes 8-level dynamic network Thomas Watteyne @ EDERC 2010

9. 9 2001, 29 Palms Demo Thomas Watteyne @ EDERC 2010

10. 10 S. Oh et al, "Tracking and coordination of multiple agents using sensor networks: system design, algorithms and experiments," Proc. of the IEEE, 2007. S. Kim et al, “Health Monitoring of Civil Infrastructures Using Wireless Sensor Networks,” IPSN, Cambridge, MA, April 2007 A. Ledezci, http://www.isis.vanderbilt.edu/projects/countersniper J. Lees et al, “Reventador Volcano 2005: Eruptive Activity Inferred from Seismo-Acoustic Observation”, Jnl, of of Volcanology and Geothermal Research, 2007 Wireless Sensor Networks Sensor Networks for Security Structural Monitoring Sniper Localization Environmental Monitoring Thomas Watteyne @ EDERC 2010

11. 11 Thomas Watteyne @ EDERC 2010 1.2 Applications

12. 12 We all agree… Thomas Watteyne @ EDERC 2010

13. 13 Building Monitoring UC Berkeley’s Center for Built Environment Seismic testing demo: real- time data acquisition hundreds of sensors on 3 floors wiring cost by far outweighs sensor cost. $200 vs. $5,000 per node in a wireless version. A few days installation (vs. weeks) Thomas Watteyne @ EDERC 2010

14. 14 Habitat Monitoring Overview – Study the Leach's Storm Petrel's Habitat – UC Berkeley, Prof. Dave Culler – Deployed during summer 2002 for 4 months on an uninhabited island 15km off the coast of Maine, USA Platform – 43 mica motes – TinyOS – Humidity, pressure, temperature, light, IR radiation Networking – Transmit-only nodes – One transmission every 70 seconds – 1.7% duty cycle – Simple CSMA MAC Thomas Watteyne @ EDERC 2010

15. 15 Precision Agriculture Overview – Micro-climate study in a potato field – Delft U. Technology, Prof. Langendoen – Deployed during Summer 2005 for 3 months in a potato field in Holland Platform – 100 motes (AtMega128L, CC1000) – TinyOS – Humidity, temperature Networking – T-MAC – Single-hop (Mint routing) – 11% duty cycle Thomas Watteyne @ EDERC 2010

16. 16 Automated Meter Reading Overview – Urban-wide Water Meter Reading – Coronis Systems, Elster group – Deployed since 2005 in Sable- d'Olonne, France Platform – 25,000 proprietary nodes Networking – Static routing tree – Parent association done at deployment – 10+ years (<.1% duty cycle) Thomas Watteyne @ EDERC 2010

17. 17 Building Automation Smart Grid Applications Industrial Automation Industrial Applications Thomas Watteyne @ EDERC 2010

18. 18 Thomas Watteyne @ EDERC 2010 1.3 The Nature of Wireless

19. 19 The Cost of Wireless Thomas Watteyne @ EDERC 2010 90%? time $ sensors computation & communication installation, connection, commissioning wired cost reduced wiring cost cellular M2M capillary M2M

20. 20 Barriers to Adoption Thomas Watteyne @ EDERC 2010 Reliability Standards Ease of use Power consumption Development cycles Node size 0%20% 60%80%100%

21. 21 Energy Efficiency OperationTimePower Energy Required Technology Fill a packet with analog samples 1 s0.025 mW25 µJ MSP430 @ 4 MHz, 80 Samples Transmit or Receive a packet 0.006 s50 mW400 µJCC2420 2.5 mJ to generate and pass this packet along 100x more than to build it Thomas Watteyne @ EDERC 2010

22. 22 Interoperability Thomas Watteyne @ EDERC 2010 The Internet

23. 23 Connectivity Thomas Watteyne @ EDERC 2010

24. 24 Reliability Reliability is challenged by: external interference multi-path fading Thomas Watteyne @ EDERC 2010

25. 25 External Interference Thomas Watteyne @ EDERC 2010

26. 26 First Challenge: External Interference IEEE802.11 (Wi-Fi) IEEE802.15.1 (Bluetooth) IEEE802.15.4 (ZigBee) Thomas Watteyne @ EDERC 2010

27. 27 Typical Tx power IEEE802.11-2007: 100mW IEEE802.15.4-2006: 1mW First Challenge: External Interference 2.4 GHz Channels 11-26 2.4835 GHz 5 MHz 2.4 GHz PHY Thomas Watteyne @ EDERC 2010

28. 28 IEEE802.11b/g/n IEEE802.11a/n First Challenge: External Interference 868 MHz 433 MHz 2.4 GHz5 GHz IEEE802.15.4 Thomas Watteyne @ EDERC 2010

29. 29 First Challenge: External Interference 45 motes * 50x50m office environment 12 million packets exchanged, equaly over all 16 channels *data collected by Jorge Ortiz and David Culler, UCB Publicly available at wsn.eecs.berkeley.edu Thomas Watteyne @ EDERC 2010

30. 30 Second Challenge: Multipath Fading Thomas Watteyne @ EDERC 2010

31. 31 Second Challenge: Multipath Fading Separate sender and receiver by 100cm Have sender send bursts of 1000 packets Have receiver count the number of received packets Move transmitter around in a 20cmx35cm square and start over Thomas Watteyne @ EDERC 2010

32. 32 Second Challenge: Multipath Fading ch.11 Thomas Watteyne @ EDERC 2010

33. 33 Second Challenge: Multipath Fading ch.11ch.12 0% reliability100% reliability Thomas Watteyne @ EDERC 2010

34. 34 Second Challenge: Multipath Fading ch.11 ch.13 ch.15 ch.17 ch.12 ch.14 ch.16 ch.18 ch.19 ch.21 ch.23 ch.25 ch.20 ch.22 ch.24 ch.26 changing channel improves performance Thomas Watteyne @ EDERC 2010

35. 35 Taking A Real-World Example Doherty, Lindsay, Simon. “Channel- Specific Wireless Sensor Network Path Data”, ICCCN 2007. 44 nodes, 26 days Thomas Watteyne @ EDERC 2010

39. 39 Pathloss RSSI does not give an indication about distance Thomas Watteyne @ EDERC 2010

40. 40 Stability over all paths, all channels Thomas Watteyne @ EDERC 2010

41. 41 2.405 GHz 2.480 GHz 802.15.4 Channels 802.11bg Channels * each dot represents 15 minutes Stability over all paths, all channels Thomas Watteyne @ EDERC 2010

42. 42 Stability over all paths, all channels Thomas Watteyne @ EDERC 2010

43. 43 Stability over all paths, all channels Thomas Watteyne @ EDERC 2010

44. 44 Thomas Watteyne @ EDERC 2010 1.4 Conclusions

45. 45 Conclusions Research – many network degrees of freedom, hence a lot of work – focus is on intra wireless sensor network communication – impact era has passed but numerous problems are still open Development – keep it simple and tailor to required application – focus is on communication between WSN and Internet – impact era is yet to come Business – WSN promise significant financial cost savings – business takes off slower than anticipated due to various reasons Thomas Watteyne @ EDERC 2010