Radio Tomographic Imaging for Ambient Assisted Living

  • Maurizio Bocca
  • Ossi Kaltiokallio
  • Neal Patwari
Part of the Communications in Computer and Information Science book series (CCIS, volume 362)


Accurate localization of people in indoor and domestic environments is one of the key requirements for ambient assisted living (AAL) systems. This chapter describes how the received signal strength (RSS) measurements collected by a network of static radio transceivers can be used to localize people without requiring them to wear or carry any radio device. We describe a technique named radio tomographic imaging (RTI), which produces real-time images of the change in the radio propagation field of the monitored area caused by the presence of people. People’s locations are inferred from the estimated RTI images. We show results from a long-term deployment in a typical single floor, one bedroom apartment. In order to deal with the dynamic nature of the domestic environment, we introduce methods to make the RTI system self-calibrating. Experimental results show that the average localization error of the system is 0.23 m. Moreover, the system is capable of adapting to the changes in the indoor environment, achieving high localization accuracy over an extended period of time.


Wireless Networks Indoor Localization Received Signal Strength Radio Tomographic Imaging 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Maurizio Bocca
    • 1
  • Ossi Kaltiokallio
    • 2
  • Neal Patwari
    • 1
  1. 1.SPAN Lab, ECE DepartmentThe University of UtahSalt Lake CityUSA
  2. 2.Automation and Systems Technology DepartmentAalto UniversityEspooFinland

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