Performance Evaluation of Indoor Geolocation Systems Talk by Emmanuel Agu

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Performance Evaluation of Indoor Geolocation
SystemsTalk by Emmanuel Agu
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Introduction

• Emerging applications for indoor geolocation
• Commercial
• Public safety
• Military
• GPS does not perform well in indoor areas
• Two leading technologies for indoor geolocation
  system
• Using RSS and WLAN infrastructure
• Using TOA and UWB technology

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How RSS Fingerprint Systems Work?

• Two phases
• Offline calibration phase Form (location-gt RSS)
  radio map (Data collection)
• Real-Time phase compare received signal using
  pattern-matching algorithms, estimate mobile
  terminal location
• Parameters affecting accuracy/performance
• Number and location of access points
• Number of training points
• Pattern matching algorithm

PM algorithms
Location-Application
RSS
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3-Tier Performance Evaluation

• Required accuracy is application-dependent!!
• Build sample location-aware applications on WPI
  campus
• Location aware campus tour
• Laptop tracking security application, etc
• Compare proposed pattern matching algorithms,
  develop new ones
• Physical Layer Performance Evaluation
• Investigate and understand factors affecting RSS

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Locus

• Java-based software framework to compare
  pattern-matching algorithms
• Calibrated for WPI Wireless LAN

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Physical Layer Performance Evaluation

• Build testbed for controlled investigation of
  physical layer parameters (number of training
  points, APs, etc)
• Framework for real-time performance evaluation of
  indoor geolocation systems using RSS in WLAN
  infrastructure.
• Uses either Locus or commercial vendor
  geolocation applications (e.g. Ekahau, Newbury
  Networks, etc)
• Why testbed?
• No time-consuming massive measurements
• Repeatable scenarios suitable for comparative
  performance evaluations

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Challenges for Testbed Design for Performance
Evaluation of Indoor Geolocation Systems

• Multiple channel simulations are necessary to
  reflect multipath between mobile terminal and
  base station cards
• Interface to layout of the building is needed to
  determine the spatial behavior of the error

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Testbed
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The Main Elements of the Testbed

• Ray tracing software
• 2D ray tracing software
• PROPSim real-time channel simulator
• EKAHAU positioning system
• RSS fingerprinting based system

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Block Diagram of Testbed
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Credits

• Prof. Kaveh Pahlavan
• Mohammad Heidari (graduate student)
• Prof. Emmanuel Agu
• Ali Taheri (student)
• Arvinder Singh (student)