The tag, transponder, active contains within it a small battery that powers communication. The electro-magnetic field emitted by the reader and antenna activates the tag, which, thanks to the energy provided by the battery, begins to transmit outside the same field, reaching high communication distances (even over 100 mt).
Response-type active tags are typically read-write, with memory capacity ranging from 64 bytes to 32Kbytes; they may have an LED light that illuminates when communication is activated and can be “queried,” to check the “state of charge ” of the battery.
There are Response type tags with integrated sensors (or with external probes attached) suitable for detecting temperature and/or a change in state. An example of a well-known active tag and quite similar to Response technology is Telepass.
