Types Of RFID System
What are the types of RFID systems?
We can sort RFID system out to four types as per different frequency scopes. Frequencies vary greatly by the standards of different countries and regions.
- Low-frequency (LF): Range scope is defined from 30 KHz to 500 KHz, though the typical frequency is 125 KHz. LF RFID has short transmission ranges, generally anywhere from a few inches to less than six feet.
- High-frequency (HF): Range scope defined from 3 MHz to 30 MHz but the most popular frequency is 13.56 MHz. The standard read range is anywhere from a few inches to several feet.
- Ultrahigh-frequency (UHF): These range from 300 MHz to 960 MHz, with the typical frequency of 433 MHz for active system and 840~960 MHz for passive system, generally be read from 25-plus feet away.
- Microwave RFID . These run at 2.45 Ghz and can be read from 30-plus feet away.
The frequency used will depend on the RFID application, with actual obtained distances sometimes varying from what is expected. For example, when the U.S. State Department announced it would issue electronic passports enabled with an RFID chip, it said the chips would only be able to be read from approximately 4 inches away. However, the State Department soon received evidence that RFID readers could skim the information from the RFID tags from much farther than 4 inches -- sometimes upward of 33 feet away.
If longer read ranges are required, using tags with additional power can increase read ranges up to 300-plus feet.