Difference Between LF HF and UHF RFID
The use of RFID has grown throughout time into countless applications. However, these applications required a different version of RFID for various purposes. These variants were based upon the frequency of the radio waves used by the tags. There are several types of RFID cards, such as Low-frequency, High-frequency, and Ultra-high frequency tags. These frequencies carry different characteristics that allow each of them with several advantages.
Low-Frequency RFID Tags
In the radio wave spectrum, the range of frequencies between 30 kHz to 300 kHz is defined as the Low-frequency band. As such, Low-frequency RFID tags are those that typically operate at 125 kHz. These low-frequency tags have a slower data reading rate compared to a higher frequency. LF tags provide uniform transmission in every direction up to 10 cm. One great benefit of LF tags is that they are less susceptible to any electromagnetic interference or noise. These tags are often used for access control applications. LF RFID tags can also transmit through thin metal layers as well.
High-Frequency RFID Tags
The High-frequency band consists of frequencies from 3 MHz to 30 MHZ. Accordingly, major High-frequency RFID cards operate at 13.56 MHZ. In comparison to Low-frequency, High-frequency systems face a moderate level of radio-wave interference. There are a plethora of applications running on High-frequency applications. Accordingly, there are many standards and compliances for High-frequency applications. These standards include ISO 15693, ISO/IEC 14443A, and ISO/IEC 14443 for the MIFARE card range. Many of the smart cards, proximity technology, and NFC tags fall under High-frequency RFID applications.
Ultra-High Frequency RFID Tags
Band of frequencies between 300 MHz to 3 GHz is defined as the Ultra-high frequency band. Mostly, the UHF systems operate at 900 MHZ to 915 MHz frequencies. Such higher frequencies would allow a superior transmission range, up to 12 meters or 40 feet. Ultra-high frequency tags have the highest data transmission rate against LF or HF. However, UHF is most susceptible to EMI and radio wave noise. Also, these tags are relatively easy to manufacture, and as such, they are cheaper than LF & HF tags. UHF is growing fast in all industries with different applications.
Summary
There are particular needs where each type of RFID card is a better fit for the specific application. However, UHF tags are the most popular for new developments in the RFID market. A more extended range of UHF cards makes it suitable for a variety of industrial applications. For LF and HF, there will always be a scope where a particular transmission range is essential. Intelligent system architects know that the complex system should instead implement a combination of these technologies rather than relying on a single choice.
The growing demand for contactless and effortless technologies will bring more focus to RFID technologies. As such, there will be room for developments where multiple RFID devices will accompany users in the future. It will be essential to observe how these technologies can overcome challenges such as metal barriers, human health concerns, data security, and data transmission interference.
