Indoor Localization Using 802.11 Time Differences of Arrival

This paper proposes a novel time-based method for determining the position of an IEEE 802.11g transmitter using multiple mutually synchronized 802.11g receivers. By means of baseband signal processing, the proposed algorithm obtains a high-resolution estimate of the time of arrival (TOA) of the long training sequence symbol at each receiver. An estimate of the position of the transmitter is obtained based on the estimation of the time differences of arrival (TDOA) of the symbols and the known fixed locations of the receivers. This paper investigates the effects of carrier and sampling clock offsets, in both frequency and phase, between nodes on the TOA and TDOA estimation error. In real-world experiments in a line of sight, low multipath indoor environment, the method was found to achieve mean errors of 42 cm per symbol for 1-D and 1.39 m per symbol for 2-D position estimation, for ranges of up to 25 m.

[1]  Juan C. García,et al.  Locally-Referenced Ultrasonic – LPS for Localization and Navigation , 2014, Sensors.

[2]  Christian Hoene,et al.  Measuring Round Trip Times to Determine the Distance Between WLAN Nodes , 2005, NETWORKING.

[3]  Visa Koivunen,et al.  Time Synchronization and Ranging in OFDM Systems Using Time-Reversal , 2013, IEEE Transactions on Instrumentation and Measurement.

[4]  K. C. Ho,et al.  A simple and efficient estimator for hyperbolic location , 1994, IEEE Trans. Signal Process..

[5]  J. Elson,et al.  Fine-grained network time synchronization using reference broadcasts , 2002, OSDI '02.

[6]  Joseph R. Cavallaro,et al.  High-resolution time of arrival estimation for OFDM-based transceivers , 2015 .

[7]  Reinhard Exel,et al.  A novel, high-precision timestamping platform for wireless networks , 2009, 2009 IEEE Conference on Emerging Technologies & Factory Automation.

[8]  Zan Li,et al.  TDOA for narrow-band signal with low sampling rate and imperfect synchronization , 2014, 2014 7th IFIP Wireless and Mobile Networking Conference (WMNC).

[9]  Juan Su,et al.  In doors location technology research based on WLAN , 2007 .

[10]  Alessandro Ferrero,et al.  A Fast, Simplified Frequency-Domain Interpolation Method for the Evaluation of the Frequency and Amplitude of Spectral Components , 2011, IEEE Transactions on Instrumentation and Measurement.

[11]  Kaveh Pahlavan,et al.  Super-resolution TOA estimation with diversity for indoor geolocation , 2004, IEEE Transactions on Wireless Communications.

[12]  Christian Mensing,et al.  Location Determination in OFDM-Based Mobile Radio Systems , 2013 .

[13]  Rosdiadee Nordin,et al.  Recent Advances in Wireless Indoor Localization Techniques and System , 2013, J. Comput. Networks Commun..

[14]  Alessandro Ferrero,et al.  A fast frequency-domain interpolation method for the evaluation of the frequency and amplitude of spectral components , 2010, 2010 IEEE Instrumentation & Measurement Technology Conference Proceedings.

[15]  Chris J. Bleakley,et al.  Survey of WiFi positioning using time-based techniques , 2015, Comput. Networks.

[16]  Cong Ling,et al.  Application of the Improved FOCUSS for Arrival Time Estimation (IFATE) algorithm to WLAN high accuracy positioning services , 2012, 2012 Ubiquitous Positioning, Indoor Navigation, and Location Based Service (UPINLBS).

[17]  Christian Hoene,et al.  Four-way TOA and software-based trilateration of IEEE 802.11 devices , 2008, 2008 IEEE 19th International Symposium on Personal, Indoor and Mobile Radio Communications.

[18]  Christian Hoene,et al.  Precise time of flight measurements in IEEE 802.11 networks by cross-correlating the sampled signal with a continuous Barker code , 2010, The 7th IEEE International Conference on Mobile Ad-hoc and Sensor Systems (IEEE MASS 2010).

[19]  Haihong Yu,et al.  Study on Improving GPS Measurement Accuracy , 2005, 2005 IEEE Instrumentationand Measurement Technology Conference Proceedings.

[20]  Henning Trsek,et al.  System integration of an IEEE 802.11 based TDoA localization system , 2010, 2010 IEEE International Symposium on Precision Clock Synchronization for Measurement, Control and Communication.

[21]  Reinhard Exel,et al.  Localisation of Wireless LAN Nodes Using Accurate TDoA Measurements , 2010, 2010 IEEE Wireless Communication and Networking Conference.

[22]  R. O. Schmidt,et al.  Multiple emitter location and signal Parameter estimation , 1986 .

[23]  Wamberto J. L. Queiroz,et al.  Localization in IEEE 802.11 networks by using the nelder-mead method , 2013, PM2HW2N '13.

[24]  T. Sauter,et al.  Clock Synchronization for Wireless Positioning of COTS Mobile Nodes , 2007, 2007 IEEE International Symposium on Precision Clock Synchronization for Measurement, Control and Communication.

[25]  Wout Joseph,et al.  Statistical validation of WLAN range calculated with propagation models for industrial environments by chipset-level received signal strength measurements , 2009 .

[26]  Rahim Tafazolli,et al.  Improved High Resolution TOA Estimation for OFDM-WLAN Based Indoor Ranging , 2013, IEEE Wireless Communications Letters.

[27]  Fang Zhao,et al.  Comparison of Super-Resolution Algorithms for TOA Estimation in Indoor IEEE 802.11 Wireless LANs , 2006, 2006 International Conference on Wireless Communications, Networking and Mobile Computing.

[28]  Jie Liu,et al.  A realistic evaluation and comparison of indoor location technologies: experiences and lessons learned , 2015, IPSN.

[29]  Thomas Kailath,et al.  ESPRIT-estimation of signal parameters via rotational invariance techniques , 1989, IEEE Trans. Acoust. Speech Signal Process..

[30]  F. Schoute,et al.  OFDM synchronisation based on the phase rotation of sub-carriers , 2000, VTC2000-Spring. 2000 IEEE 51st Vehicular Technology Conference Proceedings (Cat. No.00CH37026).