Because RFID systems generate and radiate electromagnetic waves, these systems are reasonably classified as radio equipment, and RFID systems should operate in such a way that they do not interfere with or impair other radio services. In particular, it should be ensured that RFID systems do not interfere with nearby radio and television broadcasts, mobile radio services (police, security services, industry and commerce), radio services for shipping and aviation, and cellular telephones.
RFID system operating frequency selection should take into account other radio services, not to cause interference and impact on their services. As a result, only frequency ranges specifically reserved for industrial, scientific and medical (ISM - Industrial-Scientific-Medical) applications are normally used. These frequency ranges are standardized worldwide.
In addition to the ISM frequencies, the entire frequency range up to 135 kHz is also available (in North and South America as well as in Japan: <400 kHz), because here it is possible to work with larger magnetic field strengths, which is particularly suitable for inductively coupled RFID systems.
The predominant frequencies for RFID systems are 0 to 135kHz, as well as the ISM frequencies 6.78MHz, 13.56MHz, 27.125MHz, 40.68MHz, 433.92MHz , 869.0MHz, 915.0MHz (which is not used in Europe), 2.45GMHz, 5.8GHz and 24.125 GHz. Typical RF tags (RFID systems) operate at the frequencies shown in the figure.