Sensor Networks

• Measuring traffic

Efficient management of highways and urban streets require accurate and timely information about traffic flow. Today, more than 90 percent of traffic measurements are derived from inductive loops, which are difficult to install and maintain. The aim of this project is to design and test low-cost, battery-operated, wireless sensor networks for measuring traffic. The effort involves: (1) communication protocols for these networks that conserve power and provide delay guarantees; (2) signal processing of sensor measurements to extract relevant information; (3) management of these networks in terms of deployment and diagnosis. The research is supported by Caltrans, California Department of Transportation, and National Science Foundation.
• Traffic measurements

Our traffic measurements using acoustic and magnetic sensors are available at Vehicle detection data bank. If you do use these data please acknowledge the website.

Recent Publications

• TDMA Scheduling Algorithms for Wireless Sensor Networks.
  Sinem Coleri Ergen and Pravin Varaiya. Wireless Networks, to appear, August 2009.
• Wireless sensor networks for measuring traffic
  P. Varaiya. Powerpoint presentation, William A. Anthony Distinguished Lecture, Cornell University, November 11, 2005.
• Optimal placement of relay nodes for energy efficiency in sensor networks.
  S. Coleri Ergen and P. Varaiya. ICC2006. [pdf 148K]
• Traffic surveillance with wireless magnetic sensors.
  S.-Y. Cheung, S. Coleri Ergen and P. Varaiya. Proc. 12th ITS World Congress, San Francisco, Nov. 2005. [pdf 214K]
• Energy efficient routing with delay guarantee for sensor networks.
  S. Coleri Ergen and P. Varaiya. Wireless Networks 13(5):679-690, October 2007. [pdf 148K]
• Trigonometric K clustering (TKC) for censored distance estimation,
  D. Lee, P. Varaiya and R. Sengupta. In Phoha, LaPorta and Griffin, (Eds), Sensor Network Operations, IEEE Press, May 2006. [pdf 707K]
• Traffic measurement and classfication using a single magnetic sensor,
  S-Y. Cheung, S. Coleri, B. Dundar, S. Ganesh, C-W. Tan and P. Varaiya. May 2004. 84th TRB Annual Meeting, Washington, D.C. January 2005. [pdf 264K]
• Signal processing of sensor node data for vehicle detection,
  J. Ding, S-Y. Cheung, C-W. Tan and P. Varaiya. April 2004. [pdf 133K]
• A sensor network for traffic monitoring,
  S-Y. Cheung, S. Coleri, B. Dundar, S. Ganesh, C-W. Tan and P. Varaiya. PowerPoint presentation, Plenary Talk, IPSN '04, Berkeley, CA, April 2004. [pdf 760K]
• PEDAMACS: Power efficient and delay aware medium access protocol for sensor networks,

S. Coleri and P. Varaiya. April 2004. [pdf 594K]