RFID Cards - How do they work for Access Control?

RFID, literally standing for Radio Frequency Identification, is used in most modern Access Control systems. This technology is used inside of contactless smart cards for identification and controls whether or not someone is authorised to enter a building or room. But how exactly does this technology work? Today we will be looking into how this advanced technology functions across the various frequencies available on the market.

How does RFID technology work?

When access control is installed, the card reader continually emits an RF Energy Field. It is this field which, when it has come into contact with a card, powers an aerial of copper wire which is looped inside the card body. It is that aerial which is connected to the Smart Card Chip inside of the card.

The chip in the card contains important information such as the card number, unique customer or facility code and various other types of data. The aerial in the card helps to power this chip.

Once the chip containing all the vital data is powered, the card number is then transmitted back to the reader by using the RF Field as a transmission channel. Finally, the reader transfers the card number to the access control system which will determine if the cardholder is authorised to enter.

Low Frequency – 125 KHz

There are a number of different frequencies used in Access Control methods, and you can get readers which combine these together or readers which use these separately. A very common frequency, 125 KHz, is classed as a low frequency and enables a great read range of up to 1 meter in the ideal conditions, however this low frequency technology can only transmit small amounts of data. A perfect choice for these kind of low frequency RFID Cards can be found within the HID Proximity Card and SwiftProx Card range.

These cards are most commonly suited for access control applications because of the small amount of data (customer code and card number) which needs to be translated.

Medium Frequency – 13.56 MHz

The current most popular choice, 13.56 MHz is classed as a medium frequency and can also be used for NFC purposes. Although this frequency enables a relatively short read range of around 30cm in optimal conditions, it does offer a much higher data transfer capability. This ability makes it suitable for a wide range of applications due to its shorter read range and larger data transfer function.

For a great example of a medium frequency (13.56 MHz technology which can be integrated in a wide array of applications, take a look at the MIFARE Classic EV1 4K Blank White PVC Cards.

Now that you have a better understanding of how powerful and innovative RFID technology works, we hope that you can better find the right technology for your business. If you do need any further help or would like more information, please get in touch with a member of our expert team today!