Clock Offsets in TDOA Localization

  • Nak-Seon Seong
  • Seong-Ook Park
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4239)


Time based TDOA localization systems require time or clock synch-ronization between receivers such as cellular base stations, satellites, and sensor nodes. Imperfection of time synchronization causes degradation in positioning accuracy. However if we know about its characteristics and how to estimate the clock offsets, the localization system can be properly calibrated to provide good quality of services. In this paper, hence, we present how to derive a localization error vector with independent clock offset, and illustrate its effect on the positioning errors, and then, provide a simple method of TDOA clock offset estimation from the observation of error vectors.


Sensor Node Wireless Sensor Network Error Vector Time Synchronization Clock Offset 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    Rockah, Y., Schultheiss, P.M.: Array Shape calibration using sources in unknown location Part I: Far-field source. IEEE Trans. Acoust., Speech, Signal Processing ASSP-35(3), 286–299 (1987)CrossRefGoogle Scholar
  2. 2.
    Rockah, Y., Schultheiss, P.M.: Array Shape calibration using sources in unknown location Part II: Near-field source and estimator implementation. IEEE Trans. Acoust., Speech, Signal Processing, ASSP-35(6), 724–735 (1987)CrossRefGoogle Scholar
  3. 3.
    Chen, Y.M., Lee, J.H., Yeh, C.C.: Two- dimensional angle of arrival estimation for uniform planar array with sensor position errors. In: Proc. IEE Radar, Signal Processing, vol. 140(1), pp. 37–42 (February 1993)Google Scholar
  4. 4.
    Foy, W.H.: Position-location solution by Taylor series estimations. IEEE Trans. Aerosp. Electron. Syst. AES-12, 187–194 (1976)CrossRefGoogle Scholar
  5. 5.
    Chan, Y.T., Ho, K.C.: An efficient closed-form localization solution from time difference of arrival measurements. In: Proc. IEEE ICASSP, ICASSP 1994, vol. ii, pp. II/393–II/396 (April 1994)Google Scholar
  6. 6.
    Ji, X., Zha, H.: Robust sensor localization algorithm in wireless ad-hoc sensor networks. In: Proc. IEEE ICCCN 2003, pp. 527–532 (October 2003)Google Scholar
  7. 7.
    Schmidt, R.: Least squares range difference location. IEEE Transactions on Aerospace and Electronic Systems 32(1) (January 1996)Google Scholar
  8. 8.
    Schmidt, R.: A new approach to geometry of range difference location. IEEE Transactions on Aerospace and Electronic Systems AES-8(3) (November 1972)Google Scholar
  9. 9.
    Chan, Y.T., Ho, K.C.: A simple and efficient estimator for hyperbolic location. IEEE Transactions on Signal Processing 42(8) (August 1994)Google Scholar
  10. 10.
    Schau, H.C., Robinson, A.Z.: Passive source localization employing intersecting spherical surfaces from time-of-arrival differences. IEEE Transactions on Acoustics, Speech, and Signal Processing, ASP-35 (August 1987)Google Scholar
  11. 11.
    Smith, J.O., Abel, J.S.: Closed-form least-squares source location estimation from range-difference measurements. IEEE Transactions on Acoustics, Speech, and Signal Processing, ASSP-35(12) (December 1987)Google Scholar
  12. 12.
    Fang, B.T.: Simple solutions for hyperbolic and related location fixes. IEEE Transactions on Aerospace and Electronic Systems 26(5) (September 1990)Google Scholar
  13. 13.
    Nasipuri, A., Li, K.: A Directionality Based Location Discovery Scheme far Wireless Sensor Networks. In: SNA 2002, pp. 105–111 (2002)Google Scholar
  14. 14.
    Kaplan, E.D.: Understanding GPS: Principles and Applications. Artech House Published (1996)Google Scholar
  15. 15.
    Rydström, M., Strom, E.G., Svensson, A.: Clock-offset cancellation methods for positioning in asynchronous sensor networks. In: International Conference on Wireless Networks, Communications and Mobile Computing, vol. 2, pp. 981–986 (June 2005)Google Scholar
  16. 16.
    Patwari, N., Hero III, A.O., Perkins, M., Correal, N.S., O’Dea, R.J.: Relative location estimation in wireless sensor networks. IEEE Transactions on Signal Processing 51(8), 2137–2148 (2003)CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Nak-Seon Seong
    • 1
  • Seong-Ook Park
    • 2
  1. 1.Electronics and Telecommunications Research InstituteDaejeonKorea
  2. 2.Department of Electronic EngineeringInformation and Communications UniversityDaejeonKorea

Personalised recommendations