Bike Loc a Realtime HighPrecision Bicycle Localization System

Bike. Loc: a Real-time High-Precision Bicycle Localization System Using Synthetic Aperture Radar Hongjiang Lyu, Linghe Kong, Chengzhang Li Yunxin Liu, Jiansong Zhang, Guihai Chen 2017. 8. 3 APNet 2017

Development of Smart Bicycles

Why not GPS? ÌGPS's error is at meters level. ÌIt performs poorly under tall buildings and in the tunnel.

Requirements for Bicycle Localization System 1 2 3 Portablility Little power consumption Online algorithm

A new bicycle localization system Related works: S. Kumar, S. Gil, D. Katabi, and D. Rus. Accurate indoor localization with zero start-up cost. Mobi. Com, 2014. J. Xiong and K. Jamieson. Arraytrack: A fine-grained indoor location system. NSDI, 2013. S. Nirjon, J. Liu, G. De. Jean, B. Priyantha, Y. Jin, and T. Hart. Coin-gps: indoor localization from direct gps receiving. Mobi. Sys, 2014. Bike. Loc:

Overview of Bike. Loc 1 Take Channel State Information (CSI) snapshots 2 Performing Circular Synthetic Aperture Radar 3 Determine the direction of APs

Theoretical Part Circular Synthetic Aperture Radar Relative Power Wireless Channels

Theoretical Part Ob c sta Circular Synthetic Aperture Radar Relative Power le Wireless Channels

Theoretical Part Extending to Three Dimensions Relative Power

Design of Bike. Loc z Position of x the APs y Direction of Height Sensor of Motion APs the wheel Localization Position of Real-time the wheel Localization Starting point Middle point Current point

Design of Bike. Loc

Why Wheel? Ì We use Circular Synthetic Aperture Radar (CSAR). Ì CSAR is tansition-resilient.

Hardware Prototype of Bike. Loc Laptop Mobike Antennas Gyroscope

Experimental Results Relative power among different A 2 A 1 azimuthal and polar angle with antenna pairs: A 1 A 2, A 1 A 3, A 2 A 3 and Sum of them. A 3 Accuracy: 1. 5° A 1 A 2 Sum A 2 A 3 A 1 A 3

Angle-Of-Arrival Estimation Accuracy AOA Estimation of Different Antenna Pairs:

Localization Accuracy Against Number of APs:

Localization Accuracy Error in Distance of Motion Sensor Localization：

Conclusion ÌWe design Bike. Loc, a novel design to enable accurate bicycle localization based on a subtle combination of the wheel and Wi. Fi devices. ÌWe implement a prototype of Bike. Loc. In our testbed, we showed that Bike. Loc is very promising to achieve tens of centimeters level localization accuracy.

Q&A 19