RFID is short for Radio Frequency IDentification. RFID systems consist of tags (physical markers that contain information) and readers (that can enumerate tags and read information from them, and in some systems, write information to them). RFID is typically used to identify (and obtain information about) products and equipment marked with RFID tags.
RFID is short for Radio Frequency IDentification. RFID systems consist of tags (physical markers that contain information) and readers (that can enumerate tags and read information from them, and in some systems, write information to them). RFID is typically used to identify (and obtain information about) products and equipment marked with RFID tags.
There are various different standards for RFID systems. Systems can be classified based on their operating frequency ranges:
- LF: Low Frequency (125/135 kHz).
- HF: High Frequency (13.56 MHz). Short read range, used mostly for ID cards.
- UHF: Ultra High Frequency (840 - 960 MHz). Long read range and fast data capture (reads per second). Used for stock control and distribution in large open spaces.
Besides their standard RFID tags can be categorized based on their power supply:
- Passive: Tags are powered through the RF field emitted by the RFID reader. They modulate their power dissipation or reflect portions of the reader RF signal to send data back to the reader.
- Semi-Active / Semi-Passive: Tags are powered by themselves (e.g. through an on-board battery). Tags send data to the reader by modulating their power dissipation or reflecting portions of the reader RF signal.
- Active: Tags use their own power supply (e.g. an on-board battery) to both, power themselves and to generate their own RF signal to send data to the reader. This typically allows a larger communication range than with passive and semi-passive tags.
