1. A Testbed for Evaluation of the Effects of Multipath on Performance of TOA-based Indoor Geolocation Jie He, Student Member, IEEE, Kaveh Pahlavan, Fellow, IEEE, Shen Li, Student Member, IEEE, and Qin Wang Presented by Yishuang Geng

2. RSS based localization

3. TOA based localization

4. Why we choose TOA? 1)GPS doesn’t work in indoor environment 2)RSS based localization doesn’t have good precision Application Shopping center Airport Hospital Factories Museum Why we build testbed? 1)Repeatable and controllable 2)Performance evaluation before deployement 3)Facilitate algorithm design 4)Disadvantage of transmitter/receiver taken into account

5. Multipath condition

6. Physical scenario of multipath Free space Line of sight Non Line of sight(a)Detected direct path(DDP) (b)Undetected direct path(UDP)

7. Overall architecture of the testbed

8. Emulate Channel Model: Channel emulator

9. Real time Simulate up to 8 wireless channels Multiple fading models 70MHz bandwidth 1ns time domain resolution Intel core I7 with 8 high speed FPGA board Running Linux Ubuntu

10. Ray tracing

12. Testbed implementation Emulated Impulse Response NanoLOC Nodes PROPSim C8 Server

13. Measurement scenarios Free space: inside wireless chamber LOS: Room 233, 2 nd floor, AK building NLOS-DDP: Room 320a, 3 rd floor, AK building NLOS-UDP: Corridor 3 rd floor, AK building

14. Ranging algorithm

15. Localization algorithm

17. Performance evaluation --- Ranging

18. Performance evaluation --- Localization

19. Conclusion The testbed can evaluate the performance of TOA-based indoor geolocation system in visible, controllable and repeatable emulated channel. The emulated performances are close to the performance of field test, that validates the effectiveness of the testbed in performance evaluation of TOA-based indoor geolocation.

20. Thanks Questions?