1. FacialTIAN Shuyuan1425247310/22/2014 2. popularity utility price 3. Active Tags Use a battery communicate overdistances of severalmetersSemi-passive Tags Contain built-inbatteries to powerthe chips circuitry,resist interferenceand circumvent alack of power fromthe reader signaldue to longdistance. They are differentfrom active tags inthat they onlytransmit data at thetime a response isreceivedPassive Tags Derive their powerfrom the fieldgenerated by thereader without having anactive transmitter totransfer theinformation stored 4. Frequency of RFID tags in different applicationsFrequency Appx. ReadRangeData Speed Cost ofTagsApplicationLow Frequency(125kHz)