Personal Identification Based on Radio Signal Strength for Ubiquitous Healthcare Systems

  • Lee, Jong-Shill (Department of Biomedical Engineering, Hanyang University) ;
  • Park, Sang-Hae (Research Development Team, GS FuelCell Co. Ltd.) ;
  • Chee, Young-Joon (Department of Biomedical Engineering, Hanyang University) ;
  • Kim, In-Young (Department of Biomedical Engineering, Hanyang University) ;
  • Kim, Sun-I. (Department of Biomedical Engineering, Hanyang University)
  • Published : 2007.06.30


Personal identification is essential for the automatic measurement of biosignal information in home healthcare systems. Personal identification is usually achieved with passive radio frequency identification (RFID), which does little more than store a unique identification number. However, passive RFID is not ideal for automatic identification. We present a user identification system based on radio signal strength indication (RSSI) using ZigBee for active RFID tags. Personal identification is achieved by finding the largest RSSI value from aggregated beacon messages that are periodically transmitted by active RFID tags carried by users. Obtaining reliable person!'.! identification without restricting the orientation requires a certain distance between the closest active RFID tag from the ZED and the second closest tag. The results show that the closest active RFID tag from the ZED and the second closest tag must be at least 70 cm apart to achieve reliable personal identification.


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