Review & PResentation
Locating in Fingerprint Space: Wireless Indoor Localization with Little Human Intervention Zheng Yang, Chenshu Wu, and Yunhao Liu Tsinghua University
outline LIFS
outline Background ~ Motivation ~ IPS & Site Survey Research Solution & Design Detailed Study ~ Stress-free Floor Plan ~ Fingerprint Space ~ Mapping Experimental Results Discussion Concluding Remarks
Global vs. indooR PositioninG system
vaRious indooR localization solutions
Fingerprinting-based method becomes the promising solution for ubiquitous IPS.
FinGeRPRintinG-based techniques
site suRvey
site suRvey
outline Background ~ Motivation ~ IPS & Site Survey Research Solution & Design Detailed Study ~ Stress-free Floor Plan ~ Fingerprint Space ~ Mapping Experimental Results Discussion Concluding Remarks
basic idea
basic idea
multi-dimensional scalinG
liFs desiGn
outline Background ~ Motivation ~ IPS & Site Survey Research Solution & Design Detailed Study ~ Stress-free Floor Plan ~ Fingerprint Space ~ Mapping Experimental Results Discussion Concluding Remarks
stRess-FRee FlooR Plan
stRess-FRee FlooR Plan
data collection
distance matRix
FinGeRPRint sPace constRuction
maPPinG
maPPinG Solution: Mapping corridors first, then rooms.
coRRidoR RecoGnition Build the Minimum Spanning Tree(MST) that connects all fingerprints Corridors: Fingerprints collected at corridors reside in core positions in fingerprint space, which have relatively large centrality values. Rooms: Remove corridor points from the fingerprint space and cluster the remaining points into đ?‘˜ clusters
coRRidoR RecoGnition
ReFeRence Point extRaction Reference Point Mapping: Find keys from the doors
sPace tRansFoRmation
sPace tRansFoRmation
sPace tRansFoRmation
outline Background ~ Motivation ~ IPS & Site Survey Research Solution & Design Detailed Study ~ Stress-free Floor Plan ~ Fingerprint Space ~ Mapping Experiment Results Discussion Concluding Remarks
evaluation They implemented LiFS on Android phones (Google Nexus S). They conducted experiments in a typical office building in Tsinghua University. Size of 1600m2, with 5 large rooms of 142m2, 7 small ones with different sizes and the other 4 inaccessible rooms. Totally m= 26 APs are installed (some with known locations).
evaluation ď ą They sample the floor plan every 4đ?‘š2 and obtain 292 location points over all accessible areas. ď ą They collect 600 traces by asking 4 volunteers to walk through areas of interests for 5 hours. ď ą For each trace, record WiFi with period of about 4 seconds
PeRFoRmance
outline Background ~ Motivation ~ IPS & Site Survey Research Solution & Design Detailed Study ~ Stress-free Floor Plan ~ Fingerprint Space ~ Mapping Experimental Results Discussion Concluding Remarks
discussion
discussion
conclusion
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