This document discusses indoor positioning technologies as an alternative to GPS which does not work well indoors. It outlines various positioning methods like lateration, angulation, and fingerprinting that can be used. It then surveys existing indoor positioning systems that use technologies like WiFi, Bluetooth, UWB, and inertial sensors. Specific solutions for indoor positioning on smartphones using only ambient WiFi signals and mobile sensors are also presented, such as WiFiSlam and Qualcomm's approach, which can achieve 2 to 2.5 meter accuracy.

1. Indoor Positioning
Prepared by:
Doaa Gamal
Lecturer Assistant
Faculty of Engineering – Suez Canal University
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2. Outline
• Outdoor Positioning
• Why indoor positioning needs new technology
• User requirements
• Positioning Methods
• SURVEY OF SYSTEMS for indoor positioning
• Indoor positioning on smartphones (WIFISLAM )
• Qualcomm solution
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3. Outdoor Positioning
Developed and maintained by the US Department
of Defense (DOD)
Officially known as the NAVSTAR System
(Navigation Satellite Timing and Ranging).
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History of GPS

4. Outdoor Positioning
1969—Defense Navigation Satellite System
(DNSS) formed
1973—NAVSTAR Global Positioning System
developed
1978—first 4 satellites
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History of GPS

5. Outdoor Positioning
• 1993—24th satellite launched; initial operational
capability
• 1995—full operational capability
• May 2000—Military accuracy available to all users
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History of GPS

6. Outdoor Positioning
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7. Outdoor Positioning
Differential GPS (DGPS)
Inertial Navigation Systems (INS)
Assisted GPS (AGPS)
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GPS accuracy enhancement

8. Why indoor positioning needs new
technology
• Non‐Line‐of‐Sight (NLoS) conditions
• Severe multipath and signal scattering
• high attenuation
• fast temporal changes due to the presence of people
and opening of doors
• high demand for precision and accuracy
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9. User requirements (application
requirements)
• accuracy
• coverage area
• cost
• robustness
• scalability
• number of users
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10. User requirements (accuracy)
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11. Positioning Methods
• Cell of Origin (CoO) / Proximity Detection
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12. Positioning Methods
• Centroid Determination
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13. Positioning Methods
• Lateration / Trilateration (TOA/RTOF)
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14. Positioning Methods
• Lateration / Trilateration (TDOA)
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15. Positioning Methods
• Lateration / Trilateration (RSSI)
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16. Positioning Methods
• Angulation (AOA)
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17. Positioning Methods
• Fingerprinting (FP) / Scene Analysis
• Dead Reckoning (DR)
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18. SURVEY OF SYSTEMS FOR
INDOOR POSITIONING
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Using electromagnetic waves
• GPS-based (A-GPS)
• Cellular-based
• UWB
• WLAN
• Bluetooth
• RFID

19. SURVEY OF SYSTEMS FOR
INDOOR POSITIONING
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Other techniques
• inertial navigation
• Ultra-sound
• Visible and infrared waves

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21. Indoor positioning on
smartphones
• Accelerometer
• gyroscope
• magnetometer
• barometer (iphone6)
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Sensors in Iphones

22. Indoor positioning on
smartphones (WIFISLAM )
• using only ambient Wi-Fi signals (RSSI) and mobile
sensors
• Requires an initial fingerprinting of a building
• RSSI signature map is used then to localize a mobile
device by comparing the measurements it makes
against the map.
• 2.5m accuracy
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23. Indoor positioning (Qualcomm)
• using only ambient Wi-Fi signals (RSSI) and mobile
sensors and map constraints
• Uses model-based approach
• 2m accuracy
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24. References
• Liu Et Al.: Survey Of Wireless Indoor Positioning Techniques
And Systems, Ieee Transactions On Systems, Man, And
Cybernetics—part C: Applications And Reviews, Vol. 37, No.
6, November 2007
• Naguib, Ayman, et al. "Scalable and accurate indoor
positioning on mobile devices." Indoor Positioning and
Indoor Navigation (IPIN), 2013 International Conference on.
IEEE, 2013.
• R. Mautz, “Indoor positioning technologies,” 2012,
habilitation thesis, ETH Zurich
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