TY - GEN
T1 - Push the limit of WiFi based localization for smartphones
AU - Liu, Hongbo
AU - Gan, Yu
AU - Yang, Jie
AU - Sidhom, Simon
AU - Wang, Yan
AU - Chen, Yingying
AU - Ye, Fan
PY - 2012
Y1 - 2012
N2 - Highly accurate indoor localization of smartphones is critical to enable novel location based features for users and businesses. In this paper, we first conduct an empirical investigation of the suitability of WiFi localization for this purpose. We find that although reasonable accuracy can be achieved, significant errors (e.g., 6 ~ 8m) always exist. The root cause is the existence of distinct locations with similar signatures, which is a fundamental limit of pure WiFibased methods. Inspired by high densities of smartphones in public spaces, we propose a peer assisted localization approach to eliminate such large errors. It obtains accurate acoustic ranging estimates among peer phones, then maps their locations jointly against WiFi signature map subjecting to ranging constraints. We devise techniques for fast acoustic ranging among multiple phones and build a prototype. Experiments show that it can reduce the maximum and 80-percentile errors to as small as 2m and 1m, in time no longer than the original WiFi scanning, with negligible impact on battery lifetime.
AB - Highly accurate indoor localization of smartphones is critical to enable novel location based features for users and businesses. In this paper, we first conduct an empirical investigation of the suitability of WiFi localization for this purpose. We find that although reasonable accuracy can be achieved, significant errors (e.g., 6 ~ 8m) always exist. The root cause is the existence of distinct locations with similar signatures, which is a fundamental limit of pure WiFibased methods. Inspired by high densities of smartphones in public spaces, we propose a peer assisted localization approach to eliminate such large errors. It obtains accurate acoustic ranging estimates among peer phones, then maps their locations jointly against WiFi signature map subjecting to ranging constraints. We devise techniques for fast acoustic ranging among multiple phones and build a prototype. Experiments show that it can reduce the maximum and 80-percentile errors to as small as 2m and 1m, in time no longer than the original WiFi scanning, with negligible impact on battery lifetime.
KW - Peer assisted localization
KW - Smartphone
KW - WiFi fingerprint localization
UR - http://www.scopus.com/inward/record.url?scp=84866605999&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84866605999&partnerID=8YFLogxK
U2 - 10.1145/2348543.2348581
DO - 10.1145/2348543.2348581
M3 - Conference contribution
AN - SCOPUS:84866605999
SN - 9781450311595
T3 - Proceedings of the Annual International Conference on Mobile Computing and Networking, MOBICOM
SP - 305
EP - 316
BT - MobiCom'12 - Proceedings of the 18th Annual International Conference on Mobile Computing and Networking
T2 - 18th Annual International Conference on Mobile Computing and Networking, MobiCom 2012
Y2 - 22 August 2012 through 26 August 2012
ER -