1. May 5, 2005Estevez - CS 526 - Spring 20051 Improve Radio Link Modeling in Wireless Sensor Network Simulation Ricky Estevez CS526, Spring 2005, Dr. Chow University of Colorado at Colorado Springs

2. May 5, 2005Estevez - CS 526 - Spring 20052 Wireless Sensor Networks Provide a means of communicating environmental data to an end-user Problem Domains Habitat Monitoring Wildfire Monitoring and Prevention First Responders Sensor Network

3. May 5, 2005Estevez - CS 526 - Spring 20053 First Responders Sensor Network Or lifeline as I like to call it Provide critical information to first responders in the event of an emergency

4. May 5, 2005Estevez - CS 526 - Spring 20054 Motes Use wireless sensors called motes

5. May 5, 2005Estevez - CS 526 - Spring 20055 Example Deployment First Responder – Orange Team base station mote 01010101 First Responder – Green Team First Responder – Blue Team

6. May 5, 2005Estevez - CS 526 - Spring 20056 Research Topic: RF Signal Propagation How do Radio Frequency (RF) signals behave indoors? Fact: radio signals lose strength over distance Fact: radio signals lose strength when traveling through obstructions, such as walls, floors, ceilings

7. May 5, 2005Estevez - CS 526 - Spring 20057 Attenuation Loss in signal strength is called attenuation

8. May 5, 2005Estevez - CS 526 - Spring 20058 Attenuation Example A signal travels from A to B Passes through medium M A -> M -> B Input signal strength is 500 milliwatts Output signal strength reduces to 250 milliwatts after passing through. Attenuation is approximately 4dB Excessive amount of attenuation will lead to signal loss and consequently loss of information.

9. May 5, 2005Estevez - CS 526 - Spring 20059 RF Signal Propagation Variables Physical properties of the obstruction: wood, plastic, steel, thickness Distance: line of sight versus obstructed RF type: i.e. 802.11b

10. May 5, 2005Estevez - CS 526 - Spring 200510 Modeling and Simulation Many tools exist to aid modeling these real-world variables TinyOS – mote operating system TOSSIM – simulate TinyOS code TinyViz – visual TOSSIM

11. May 5, 2005Estevez - CS 526 - Spring 200511 TinyViz is Extensible Achieved through plugin capability Built-in RadioModel plugin Excellent starting point Additional variables can be modeled

12. May 5, 2005Estevez - CS 526 - Spring 200512 Plugin Model Comparison VariablesRadio Model PluginObstructed Radio Model Plugin DistanceYes RF signal typeNo Obstruction attenuationNoYes 2D ObstructionsNoYes 3D ObstructionsNo

13. May 5, 2005Estevez - CS 526 - Spring 200513 My Research Goals Enhance Jeff Rupps Obstructed Radio Signal Model Plugin: RF signal type 3D obstructions, floor, ceilings, and walls (compound computation) More robust obstruction attenuation specification (signal type, distance)

14. May 5, 2005Estevez - CS 526 - Spring 200514 Prototype Screenshot

15. May 5, 2005Estevez - CS 526 - Spring 200515 Continued Research Indoor attenuation represents a complex set of variables Precise implementation method is TBD Incorporate the Java 3D API. Porting this to TinyViz is TBD

16. May 5, 2005Estevez - CS 526 - Spring 200516 References Rupp, Jeff. Radio Signal Obstuction Plug-in for TinyViz. CS526 Fall 2003. Department of Computer Science, University of Colorado at Colorado Springs. 1420 Austin Bluffs Parkway, Colorado Springs, CO 80933-7150. Mainwaring, Alan, Polastre, Joseph, Szewczyk, Robert, Culler, David, Anderson, John. Wireless Sensor Networks for Habitat Monitoring. Intel Research Laboratory, Berkeley. EECS Department, University of California at Berkeley. College of the Atlantic, Bar Harbor, Maine. Godavari, Ganesh. Chow, Edward, C. First Responders Sensor Network (FRSN). Final Report for NISSC Fall 2003 Project. Department of Computer Science, University of Colorado at Colorado Springs. 1420 Austin Bluffs Parkway, Colorado Springs, CO 80933-7150.