RFID Active Tags Transponders ...

RFID Active Tags Transponders: Understanding AIT Capabilities

... "In active RF tags, the labels are known as tags or transponders. They contain information that can range from a permanent ID number programmed into the tag by the manufacturer to a variable 128-kilobyte memory that can be programmed by a controller using RF energy. The controller is usually referred to as a reader or interrogator. An interrogator and a tag use RF energy to communicate with each other. The interrogator sends an RF signal that 'wakes up' the tag, and the tag transmits information to the interrogator. The interrogator also can write new information on the tag, thus permitting a user to alter the tag's information within the effective range. " ...