RFID
RFID means Radio Frequency IDentification, i.e. identification using radio signals. An ID Tag sends a code to a receiver, either as an answer to a request or as proactive signal every second, minute or hour.
RFID is available in several variations that use different radio frequencies. These systems are divided into active or passive RFID.
Active RFID
Active RFID uses ID Tags that send an identification code to a receiver, usually at fixed intervals or if movement is detected.
Active RFID requires ID Tags that have their own power supply, usually in the form of a battery which means they are more expensive and require handling.
Passive RFID
Passive RFID use ID Tags that can respond to requests. The advantage of passive technology is that it typically utilises energy in the radio signal to answer the request and so passive ID Tags do not require their own power supply.
Since some materials may weaken radio signals, the actual positioning of passive ID Tags is very important.
Active RFID:
- Battery
- Limited information storage
Passive RFID:
- ID Tags and readers are inexpensive
- No batteries required
- Many ID Tags can be read at one time
- Requires infrastructure for readers
- Battery has to be recharged or replaced
- Cost of ID Tags
Passive RFID:
- Requires infrastructure for readers
- In the case of short-range RFID, normally requires a person to operate the reader
