RFID frequencies
All RFID technologies rely on the use of harmless, low power radio signals, which convey information to and from a tag, and provide power for it (in the case of passive tags).
A number of frequencies are commonly used for RFID systems; each has its own benefits and challenges:
Low Frequency (LF) tags are the oldest of all the RFID technologies. Operating at and around 125 kHz, these tags are widely available in a diverse range of packaged formats, and tend to provide relatively short ranges (typically tens of cm), and be relatively accommodating of environmental conditions (notably the presence of water). LF tags are relatively expensive because of their construction, are often bulky, and can generally only be read as single tags.
High Frequency (HF) tags operate at 13.56 MHz, a frequency available for use globally. HF tags can be read in large populations, at ranges of up to around 1m. These tags are relatively inexpensive, and were the first to be available in thin, flexible form factors (so called ‘smart labels’). |
