1. ETH Zurich Engineering Geodesy - Prof. Dr. H. Ingensand Overview of Current Indoor Positioning Systems Dr. Rainer Mautz ETH Zürich Institute of Geodesy and Photogrammetry 3rd BALTIC-SWISS GEODETIC SCIENCE WEEK, Sept. 10-12, 2008, Tallinn

2. ETH Zurich Engineering Geodesy - Prof. Dr. H. Ingensand Positioning Requirements Overview of Systems GNSS Alternative Positioning Systems Conclusions & Outlook Contents 1. Positioning Requirements 2. Overview of Systems 3. GNSS 4. Alternative Positioning Systems 5. Conclusions & Outlook

3. ETH Zurich Engineering Geodesy - Prof. Dr. H. Ingensand User Requirements: availability:100% of the time timeliness:realtime reliability:no failures hybrid systems: to be avoided local installations:none accuracy:mm - cm coverage:global all environments: indoors: household, office & factory outdoors: urban & rural dynamic Positioning Requirements Overview of Systems GNSS Alternative Positioning Systems Conclusions & Outlook

4. ETH Zurich Engineering Geodesy - Prof. Dr. H. Ingensand Classification of Positioning Systems:  Signal wavelength (Radio Frequencies, Light Waves, Ultrasound, RFID, Terahertz)  Principle (trilateration, triangulation, signal strength)  Environment (indoor, outdoor, urban, rural, remote)  Active / passive sensors  Accuracy (μm – km)  Application (industry, surveying, navigation) Positioning Requirements Overview of Systems GNSS Alternative Positioning Systems Conclusions & Outlook

5. ETH Zurich Engineering Geodesy - Prof. Dr. H. Ingensand Positioning Requirements Overview of Systems GNSS Alternative Positioning Systems Conclusions & Outlook 1 m 10 m 100 m 1 km 10 km Indoor Outdoor Range 10 μm 100 μm 1 mm 1 cm 1 dm 1 m 10 m 100 m Accuracy graphic: Rainer Mautz

6. ETH Zurich Engineering Geodesy - Prof. Dr. H. Ingensand Positioning Requirements Overview of Systems GNSS Alternative Positioning Systems Conclusions & Outlook 1 m 10 m 100 m 1 km 10 km Indoor Outdoor Range 10 μm 100 μm 1 mm 1 cm 1 dm 1 m 10 m 100 m Accuracy graphic: Rainer Mautz

7. ETH Zurich Engineering Geodesy - Prof. Dr. H. Ingensand Positioning Requirements Overview of Systems GNSS Alternative Positioning Systems Conclusions & Outlook 1 m 10 m 100 m 1 km 10 km Indoor Outdoor Range 10 μm 100 μm 1 mm 1 cm 1 dm 1 m 10 m 100 m Accuracy graphic: Rainer Mautz

8. ETH Zurich Engineering Geodesy - Prof. Dr. H. Ingensand Most Geodetic Applications Positioning Requirements Overview of Systems GNSS Alternative Positioning Systems Conclusions & Outlook 1 m 10 m 100 m 1 km 10 km Indoor Outdoor Range 10 μm 100 μm 1 mm 1 cm 1 dm 1 m 10 m 100 m Accuracy graphic: Rainer Mautz Most Geodetic Applications

9. ETH Zurich Engineering Geodesy - Prof. Dr. H. Ingensand GNSS – Performance: SystemPrinciple Coverage Real- time AccuracyRange Signal Frequency Data Rate MarketCost Outdoo r Indoor Geodetic GNSS TOA, lateration, differential technique ( )  mmglobalRF20 Hzyes moderate to high in addition:  strong attenuation  fading: reflections, diffraction, scattering  no general model no direct line-of- sight:  obstacles  multipath limitations: Positioning Requirements Overview of Systems GNSS Alternative Positioning Systems Conclusions & Outlook

10. ETH Zurich Engineering Geodesy - Prof. Dr. H. Ingensand GPS (United States) GLONASS (Russia) Galileo (EU) Beidou, i.e. Compass (China) Current number31 MEO16 MEO1 MEO1 MEO, 4 GEO Number of satellites in space 2013:40 satellites (open sky) Implications on indoor environments ? marginal Other improvements: integrity, anti-jam power, security, clocks! Future number30 MEO24 MEO30 MEO27 MEO, 5 GEO Full operational capability 199520112013ca. 2010 number of satellites gain Positioning Requirements Overview of Systems GNSS Alternative Positioning Systems Conclusions & Outlook Today: 10 satellites (open sky)

11. ETH Zurich Engineering Geodesy - Prof. Dr. H. Ingensand Material[dB]Factor [-] Glass1 - 40.8 – 0.4 Wood2 - 90.6 – 0.1 Roofing Tiles / Bricks5 - 310.3 – 0.001 Concrete12 - 430.06 – 0.00005 Ferro-Concrete29 - 430.001 – 0.00005 Attenuation of various building materials (L1 = 1500 MHz) Stone (1997) Signal Strength in Decibel Watt of GNSS Satellites Environment[dBW] Satellite+14signal strength delivered from satellite Outdoors-155unaided fixes OK for standard receivers Indoors-176decode limit for high sensitive receivers Underground-191decode limit for aided, ultra-high sensitive receivers Indoors: 100 times weaker underground: 10000 times weaker Positioning Requirements Overview of Systems GNSS Alternative Positioning Systems Conclusions & Outlook

12. ETH Zurich Engineering Geodesy - Prof. Dr. H. Ingensand Assisted GNSS (AGNSS, AGPS) ephemeris, almanac via mobile phone (+) hot start, quicker position fix (-) long acquisition times indoors (-) high power needs for high sensitivity (-) accuracy degrades to m-level indoors How to overcome attenuation?  Increase receiver sensibility  Increase satellite signal power  Use ultra wideband GNSS signals Positioning Requirements Overview of Systems GNSS Alternative Positioning Systems Conclusions & Outlook graphic from: www.semsons.com

13. ETH Zurich Engineering Geodesy - Prof. Dr. H. Ingensand Locata: Terrestrial pseudolite transceivers Alternative Positioning Systems Positioning Requirements Overview of Systems GNSS Alternative Positioning Systems Conclusions & Outlook Picture from Barnes et al. (2003) 6thIinternational Symposium on Satellite Navigation Technology, Melbourne, Australia

14. ETH Zurich Engineering Geodesy - Prof. Dr. H. Ingensand SystemPrinciple Outdoo r Indoor Real- time AccuracyRange Signal Frequency Data Rate MarketCost Locata TOA, lateration 2 mm static 1 cm RTK, 2 - 3 kmRF1 Hz in progress high Locata – Key Parameters: (+) RTK: 1 – 2 cm deviations at 2.4 m/s (+) signal magnitude stronger than GNSS (+) indoors dm Problem: multipath (low elevation) Positioning Requirements Overview of Systems GNSS Alternative Positioning Systems Conclusions & Outlook Picture from J. Barnes, C. Rizos, M. Kanli, A. Pahwa „A Positioning Technology for Classically Difficult GNSS Environments from Locata“, IEEE Conference, San Diego California, 26 April 2006

15. ETH Zurich Engineering Geodesy - Prof. Dr. H. Ingensand iGPS iGPS transmitter and sensor during a test in a tunnel Positioning Requirements Overview of Systems GNSS Alternative Positioning Systems Conclusions & Outlook

16. ETH Zurich Engineering Geodesy - Prof. Dr. H. Ingensand iGPS – “laser resection” PrincipleOutdoorIndoor Real- time AccuracyRange Signal Frequency Data Rate MarketCost TOA angular measurements 0.1 – 0.2 mm 2 - 50 mRF40 Hzin progresshigh Key design:  two or more fixed transmitters  rotating fan-shaped laser beams  infrared signal  various sensors detect arrival times  position determination with spatial forward intersection graphic from Metris Positioning Requirements Overview of Systems GNSS Alternative Positioning Systems Conclusions & Outlook

17. ETH Zurich Engineering Geodesy - Prof. Dr. H. Ingensand Localisation using direction of arrival PrincipleOutdoorIndoor Real- time AccuracyRange Signal Frequency Data Rate MarketCost TOA, Triangulation 2° angle100 mRF-in progresslow Key design:  mobile units are transmitters  min. 3 receiving units with 4 patch antennas each  accuracy currently 2 angular degrees  position determination with trilateration graphic from Fraunhofer Institute Positioning Requirements Overview of Systems GNSS Alternative Positioning Systems Conclusions & Outlook α Δt

18. ETH Zurich Engineering Geodesy - Prof. Dr. H. Ingensand Ultrasound Systems – Crickets, Active Bat, Dolphin SystemPrinciple Outdoo r Indoor Real- time AccuracyRange Signal Frequency Data Rate MarketCost Cricket TOA, lateration  1 – 2 cm10 multrasound1 Hz develop ment low Active Bat TOA, lateration  1 – 5 cm1000 m 2 ultrasound75 Hznomoderate DOLPHIN TOA, lateration  2 cm room scale ultrasound20 Hznomoderate Picture: Cambridge University Positioning Requirements Overview of Systems GNSS Alternative Positioning Systems Conclusions & Outlook

19. ETH Zurich Engineering Geodesy - Prof. Dr. H. Ingensand Problems:  dependency on temperature  maximal range  deployment of reference beacons  multipath  reliability  interference with other sound sources Positioning Requirements Overview of Systems GNSS Alternative Positioning Systems Conclusions & Outlook Ultrasound Systems – Crickets, Active Bat, Dolphin SystemPrinciple Outdoo r Indoor Real- time AccuracyRange Signal Frequency Data Rate MarketCost Cricket TOA, lateration  1 – 2 cm10 multrasound1 Hz develop ment low Active Bat TOA, lateration  1 – 5 cm1000 m 2 ultrasound75 Hznomoderate DOLPHIN TOA, lateration  2 cm room scale ultrasound20 Hznomoderate

20. ETH Zurich Engineering Geodesy - Prof. Dr. H. Ingensand Positioning based on Signal Strength All signals can be used: WLAN, Ultrasound, RF, GPRS, etc. Problems:  reliability  accuracy SystemPrinciple Outdoo r Indoor Real- time AccuracyRange Signal Frequency Data Rate MarketCost SonitorRSSI, Cell ID  m-level15 multrasound0.3 Hzyeslow RFID Signal Strength  dm-m20 m RF, 866 MHz nolow Picture from: USC Robotics Research Lab Positioning Requirements Overview of Systems GNSS Alternative Positioning Systems Conclusions & Outlook

21. ETH Zurich Engineering Geodesy - Prof. Dr. H. Ingensand Outdoors: GNSS dominating system for open-sky Indoors: No overall solution yet Several indoor systems on the market  low accuracy  sophisticated setups  limited coverage area  inadequate costs  signals will penetrate buildings  use existing infrastructure  for higher accuracy are local installations unavoidable Project: Building own indoor positioning system! Conclusions Outdoors: GNSS dominating system for open-sky Indoors: No overall solution yet Several indoor systems on the market  low accuracy  sophisticated setups  limited coverage area  inadequate costs Outlook  signals will penetrate buildings  use existing infrastructure  for higher accuracy are local installations unavoidable Project: Building own indoor positioning system! Positioning Requirements Overview of Systems GNSS Alternative Positioning Systems Conclusions & Outlook

22. ETH Zurich Engineering Geodesy - Prof. Dr. H. Ingensand End