RFID systems can be broken down by the frequency band within which they operate: low frequency, high frequency, and ultra-high frequency. There are also two broad categories of RFID systems-passive and active. In the sections below we will explore the frequencies and types of RFID systems.
RFID Frequencies
Frequency refers to the size of the radio waves used to communicate between RFID system components. RFID systems throughout the world operate inlow frequency (LF),high frequency (HF)andultra high frequency (UHF) bands. Radio waves behave differently at each of these frequencies with advantages and disadvantages associated with using each frequency band.
If an RFID systems operates at a lower frequency, it has a shorter read range and slower data read rate, but increased capabilities for reading near or on metal or liquid surfaces. If a system operates at a higher frequency, it generally has faster data transfer rates and longer read ranges than lower frequency systems, but more sensitivity to radio wave interference caused by liquids and metals in the environment.
The RFID frequency spectrum
RFID is considered as a non specific short range device. It can use frequency bands without a license. Nevertheless, RFID has to be compliant with local regulations (ETSI, FCC etc.)
- LF : 125 kHz – 134,2 kHz : low frequencies,
- HF : 13.56 MHz : high frequencies,
- UHF : 860 MHz – 960 MHz : ultra high frequencies,
- SHF : 2.45 GHz : super high frequencies
