230 likes | 381 Views
To localise or to be localised with Wi-Fi in the Hubei Museum?. Edward Verbree, Sisi Zlatanova, Karl van Winden, Eva van der Laan, Antigoni Makri, Li Taizhou, Ai Haojun. Introduction. MSc Geomatics - DaRen Syntheses Project Hubei Provincial Museum – Wuhan China Localisation
E N D
To localise or to be localised with Wi-Fi in the Hubei Museum? Edward Verbree, Sisi Zlatanova, Karl van Winden, Eva van der Laan, Antigoni Makri, Li Taizhou, Ai Haojun
Introduction • MSc Geomatics - DaRen Syntheses Project • Hubei Provincial Museum – Wuhan China • Localisation • Wi-Fi Fingerprinting • Wi-Fi Monitoring • Wi-Fi Monitored Fingerprinting
Introduction • The overall goal of the project is to investigate the potential of a 3D indoor navigation systems and raise awareness of the possibilities provided by the technology for every-day users. • This goal is achieved by creating a 3D multi-purpose indoor navigation application named DaRen • Chinese words Da “intelligence, accessibility” and Ren “people”
ApplicationNavigation • Localisation • Routing • Visualisation
LocalisationResearch Question What are the possibilities of Wi-Fi monitoring in comparison to the commonly known fingerprinting method for the purpose of a 3D indoor navigation system?
LocalisationGranularity • Localisation ≠ (Point) Positioning • Localisation = Place oriented (floor, room, exhibition) • Localisation = Needed as starting place for routing • Localisation = Needed for location based services (sec)
Wi-Fi Fingerprinting • Existing WLAN-infrastructure can be used • Every second a location can be given • No privacy issues regarding storage of locations • Measurements of Signal Strength Reference Points • Creation of Radio Map • Location Determination
Measuring Procedure • Offline / Training Phase: • Measurements RSS have been performed in 4 directions • Time of measuring: 1 minute / direction • Creating probability radio map: • Consists of mean value and standard deviation • Online / Localisation: • Calculating the most probable location
Wi-Fi FingerprintingResults High Spatial Resolution of Reference Points + Probabilistic RSS values = Accurate Localisation Implemented @ Wuhan University
Wi-Fi FingerprintingLimitation • Device driven (Wi-Fi scanning) • Apple devices excluded • ‘Space segment’ (Wi-Fi Access Points) not under control • Access Point re-configuration requires update of radio map
Wi-Fi Monitoring • Beacon frames • Send by ALL mobile devices (smartphones, laptops, etc.) in order to connect to Access Point • Iff Wi-Fi is on (Free Internet in Museum) • Device doesn’t have to be connected • Wi-Fi Monitor – MeshliumXtreme: Receives and stores • MAC-address, • Strength of Signal Indicator (%), • Timestamp (Date/Time), • Vendor (Apple, Samsung, Nokia, etc) • Advantages • No additional application is required to acquire RSSI • Data can be stored at an external database, which can be used to provide information to museum and users every moment of the day
Wi-Fi MonitoringApplications • Localisation • Proximity (near) to Wi-Fi monitor • Distance to monitor • RSSI gives indication in ‘open’ space • Wi-Fi Monitored Fingerprinting possible • Business information • Count of (Wi-Fi enabled) visitors • Time spent at exhibation • Direction of movement of visitors (with two or more monitors) • Crowd control • No need of installed app, no user-involvement
Wi-Fi MonitoringLimitation • Relies on probe request frames of devices • Interval between two successful scans can be large • Not all mobile devices were scanned • Newer types of devices > update of firmware of monitor • Privacy Issues: Renew Recycling Bins • “City of London bans data-collecting Wi-Fi smart bins
Wi-Fi Monitored FingerprintingTest • Two Meshlium Xtreme Wi-Fi Monitors part of Access Point configuration while creating radio-map • Correlation determined between RSSI (Monitor) and RSS (devices) • RSSI Radio Map created for each Monitor
Wi-Fi Monitored Fingerprinting • RSSI Radio Map First monitor
Wi-Fi MonitoredFingerprinting • Where am I?
To localise or to be localisedConclusions To localise (to sniff) App needed at devices (if possible) Happy few (early adopters) Wi-Fi infrastructure not under control for localisation purposes or To be localised (to be sniffed) Web-application can be used at devices Everyone (Free Internet) Dedicated Wi-Fi-Monitors under control for localisation purposes