1. IEEE Globecom OWC, Miami, FL, December 2010 1 3-D Optical Wireless Localization Mehmet Bilgi, Murat Yuksel, and Nezih Pala mbilgi@cse.unr.edu, yuksem@cse.unr.edu, npala@fiu.edu Computer Science and Engineering University of Nevada, Reno Project Website: http://www.cse.unr.edu/~yuksem/fso-manet.htm

2. IEEE Globecom OWC, Miami, FL, December 2010 2 Outline Motivation Literature Survey Packet-Based Simulation for Multi-Transceiver Structures Localization Results Summary and Conclusions

3. IEEE Globecom OWC, Miami, FL, December 2010 Localization in MANETs: Motivation Providing contextual (location) information to data (motion, light measurement) is important Geographical routing protocols can use localization: ID-to-Location mapping

4. IEEE Globecom OWC, Miami, FL, December 2010 Localization Approaches Range-only Orientation-only Using both Using landmarks and mapping (by robotics community)

5. IEEE Globecom OWC, Miami, FL, December 2010 Localization Literature Range-only: estimate ranges using power loss measurements, assume simple path RF propagation 3 anchors in 2D, 4 in 3D Saravese 02 introduced a tuning phase Whitehouse 02 used both signal strength and acoustic time of flight

6. IEEE Globecom OWC, Miami, FL, December 2010 Localization Literature Orientation-only: Use bearing and sectoring devices Assign a direction to incoming signal Niculescu 03 used a set of ultrasound and an antenna array Found: localization error increases as one goes away from the anchors Hybrid: Akella 07 used FSO to achieve 100% localization extent in a connected graph

7. IEEE Globecom OWC, Miami, FL, December 2010 Packet-Based Simulation of FSO- MANETs NS-2 extensions Contributed FSO propagation Accounting for noise Alignment Lists

8. IEEE Globecom OWC, Miami, FL, December 2010 Packet-Based Simulation of FSO- MANETs down target target [n] down target up target down target link layer interface queue MAC wireless phy up target channe l mac up target target [k] down target up target down target link layer interface queue MAC wireless phy channe l target [0] down target up target link layer interface queue MAC wireless phy channe l mac up target mac up target AODV wireless channel up target Default NS-2 mobile node design had only 1 interface Introduced FSO propagation at wireless channel alignment list Introduced alignment lists for each interface

9. IEEE Globecom OWC, Miami, FL, December 2010 9 3-D FSO Localization Orientation-only localization with two localized neighbors: A third node can triangulate using the advertised normals received from two other GPS-enabled nodes. Location Tx Normal Location Tx Normal

10. IEEE Globecom OWC, Miami, FL, December 2010 10 3-D FSO Localization: Heuristics Anchor Distance Angular Priority Arrival Times

11. IEEE Globecom OWC, Miami, FL, December 2010 11 3-D FSO Localization How to select 2 out of many neighbors? Acceptable, predictable error

12. IEEE Globecom OWC, Miami, FL, December 2010 GPS-Enabled Node Effect Increasing Trend Decreasing Trend

13. IEEE Globecom OWC, Miami, FL, December 2010 Message Exchange Overhead High localization extent with reasonable overhead

14. IEEE Globecom OWC, Miami, FL, December 2010 14 Conclusions Introduced optical-only 3-D localization techniques, Provided accuracy results with respect to: Node density GPS-enabled node count Localization overhead Localization is possible using a direction-only approach without extra hardware

15. IEEE Globecom OWC, Miami, FL, December 2010 15 Future Work Introduce realistic 3-D terrain models Experiment using the prototype

16. IEEE Globecom OWC, Miami, FL, December 2010 16 Thank you! THE END Acknowledgments This work was supported by the U.S. National Science Foundation under awards 0721452 and 0721612 and DARPA under contract W31P4Q-08-C-0080