Optimal Sensor Placement for Freeway Travel Time Estimation

  • Xuegang(Jeff) Ban
  • Ryan Herring
  • J.D. Margulici
  • Alexandre M. Bayen


This article presents a modeling framework and a polynomial solution algorithm for determining optimal locations of point detectors used to compute freeway travel times. First, an objective function is introduced to minimize the deviation of estimated and actual travel times of all individual sub-segments of a freeway route. By discretizing the problem in both time and space, we formulate it as a dynamic programming model, which can be solved via a shortest path search in an acyclic graph. Numerical examples are provided to illustrate the model and algorithm using microscopic traffic simulation and GPS data from the Mobile Centuryexperiment recently conducted by the University of California, Berkeley, Nokia and California Department of Transportation (Caltrans).


Optimal Sensor Link Travel Time Loop Detector Travel Time Estimation Actual Travel Time 
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.


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The authors would like to thank the four anonymous referees for their insightful comments and helpful suggestions on an earlier version of the paper. This research is partially supported by the California Department of Transportation (Caltrans).


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Copyright information

© Springer-Verlag US 2009

Authors and Affiliations

  • Xuegang(Jeff) Ban
    • 1
  • Ryan Herring
    • 2
  • J.D. Margulici
    • 2
  • Alexandre M. Bayen
    • 2
  1. 1.Rensselaer Polytechnic InstituteCaliforniaU.S.A
  2. 2.University of CaliforniaCaliforniaU.S.A

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