This is an RFID technology overview for those wanting to purchase an RFID device.
Introduction
RFID (Radio Frequency Identification) technology is present in most businesses and establishments today. It helps identify or track various entities, such as objects or humans. RFID tech can be found in production, packaging, shelving, and ID systems, to name a few. Previous laborious processes of identifying things can be automated using RFID.
Before learning how to choose an RFID card and reader, first read about the technology behind RFID and the different standards associated with them below.
What's Behind RFID Tech
RFID technology is possible because of how electromagnetic waves work. These waves can be transmitted using coils or antennas from a transmitter (such as a card reader) to a receiver (such as an RFID Card or Key FOB) and vice versa. Certain modulation techniques permit data (through electromagnetic waves) to be transferred from one transmitting device to a receiving device. Microchips inside these modules perform certain tasks, such as storing, transmitting, and receiving data.Â
Additionally, inductive power can be transferred from a powered device (such as a Card Reader) to a non-powered device (such as a card or key FOB). This allows the non-powered device to operate without bulky batteries.
What are the Common Frequencies USed in RFID
- Low frequency (125 KHz )— LF-RFID is widely used in proximity cards and used for identification purposes. It has low bandwidth, transmitting fewer digital data per second than its higher-frequency counterparts. Low-bandwidth RFIDs can be used in access control systems, manufacturing, livestock, pets, and automotive keyless entry systems. Because of their low bandwidth, they have fewer memory locations to store data than their HF RFID counterpart. They are also less secure, allowing them to be cloned or copied. LF RFID’s advantage is its lower susceptibility to noise. They’re also better suited in liquid and metal environments. The read range of LF RFIDs is up to 10cm.
- High Frequency (13.56 MHz)—This RFID carrier frequency can accommodate higher bandwidths and use more memory storage and data. It’s primarily used in smart card technologies. Several international standards (ISOs) are implemented for HF RFIDs, such as ISO/IEC 15693 (vicinity cards), ISO/IEC14443A, B (proximity cards), and ISO/IEC 18092 (NFCs). These standards help so that HF-RIFD implementation is the same worldwide. HF RFIDs can have more secure encryption schemes. Common HF RFID protocols include MIFARE Classic, MIFARE DesFire, iClass, FelCa, Legic, etc. The read range of HF RFIDs is up to 30cm.
- Ultra-High Frequency (856 MHz—960 MHz)—These RFIDs are usually used in mining, construction, manufacturing, cargo, etc. They have a long read range, typically between 25m and 100m. The downside of UHF RFIDs is that they’re more expensive and cause high interference when used with metal or liquid environments.
What are the Common Formats USed in RFID
RFID cards use different formats that your RFID reader should recognize. Readers that recognize multiple formats or technologies exist, and you should be aware of them too.
- EM4100, TK4100 – EM4100, and TK4100 are ICs used in 125KHz RFID read-only transponders. This non-proprietary format uses a 64-bit array that’s generally suited for identification. There is no encryption involved in this format. The EM4100 and TK4100 are usually embedded in cheap RFID cards and readers.
- MIFARE (MIFARE Classic, Plus, and DESFire)—MIFARE is a format introduced by NXP semiconductors for use in their RFID chips. This format uses an HF-RFID frequency of 13.56 MHz. MIFARE is secure, uses encryption, and is generally preferred over non-secure formats (such as EM4100 or the HID Proximity), especially for environments where security is a concern. Over the years, several versions of MIFARE have come out, such as MIFARE Plus and DESFire, further enhancing the security of the MIFARE format.
- HID Proximity—HID Global Corporation introduced this format in their 125 KHz proximity cards. It has become an open-source industry standard for most industries using access control technology. HID Proximity uses a 26-bit (H10301) format. However, this format is insecure compared to the modern format used by smart cards.
- iClass – iClass is a proprietary format introduced by HID Global for contactless smart card solutions. iClass uses a High Frequency 13.56 MHz carrier and uses various security schemes. Within iClass comes different versions, including iClass Classic, iClass SE, iClass Seos, etc. Some iClass devices are multi-technology that can access different MIFARE and even old HID Proximity formats.
Conclusion
This RFID technology overview presented how RFID works, the different frequencies, and the common formats RFIDs have. By knowing this information, you should be able to select the appropriate RFID for your system.
