How to Choose the Right RFID Frequency for Your Application
Radio frequency identification (RFID) is classified as a type of Automatic Identification and Data Capture (AIDC) technology. AIDC methods automatically identify objects, collect data about them, and enter those data directly into computer systems with little or no human intervention.
RFID methods utilize radio waves to accomplish this. At a simple level, RFID systems consist of three components: an RFID tag or smart label, an RFID reader, and an antenna. RFID tags contain an integrated circuit and an antenna, which are used to transmit data to the RFID reader.
In order for the RFID readers and tags to communicate, they must be tuned to the same frequency. This is not unlike adjusting your radio dial to change to a different station, which broadcasts at a different frequency than the previous station that you were listening to. The most common RFID frequencies used for RFID applications are:
- Low frequency (9-135 KHz)
- High frequency (13.553-15.567 MHz)
- Amateur radio band (430-440 MHz)
- Ultra-high frequency (860-930 MHz)
- Microwave (2.4-2.4835 GHz, 5.8 GHz)
The frequency that you choose will depend on the type of RFID application, whether there are any mandates to be met, such as the DoD RFID mandate, and what country the application will be used in. Low-frequency (LF) tags, for example, are better for tagging nonmetal objects that may have a high water content. However, the read range of low-frequency tags is less than a foot.
By contrast, high-frequency (HF) tags can be used for metallic objects and objects with a higher water content, and they have a read range of about three feet. While ultra-high frequencies (UHF) have a greater read range and can transmit data faster than LF and HF tags, they consume more power and are not as versatile when it comes to the types of materials that they can penetrate. In order for their data to be read, UHF tags also require a clear pathway between the reader and the tag. Therefore, they are more suitable in situations where boxes will be scanned as they pass through dock doors.
Aside from the type of RFID application, the geographical region where the application will be used is important when selecting the right frequency, as different regions have different standards and regulations. The frequency ranges listed above pertain to North America.
Because of the many factors involved in determining the optimum frequency for your RFID application, it’s a good idea to consult with a company that specializes in implementing RFID systems.