Before we answer the big question in this article, let’s start with something simple. What is RFID? RFID is short for Radio Frequency Identification. It is widely used to identify, authorize and/or authenticate a person. It has been used a lot at companies for an attendance system and also in cars to automate toll booths. The major advantage of this system is that it doesn’t have to be in the line of sight of the reader, unlike barcodes and QR codes. However, this same feature can also turn out to be disadvantageous especially in credit cards. Now that we know what RFID is let’s find out how it works.

Working

RFID is a method of automatic identification and data capture (AIDC). So when a receiver comes in the vicinity of the Radio Frequency Tag it picks up the required data transmitted by this tag. The reader sends out a Radio signal of low frequency (13.56 MHz) for a range of about 10-100 cm at given time intervals. For every iteration of this process, the antennae wait for a response from any recognized device. The device then gets powered on and sends its own feedback with data that it is programmed to send. The Receiver receives this data and does the required processing.

There are two types of RFID systems:

• Active RFID: These systems usually have their own power source. These devices are generally used for long-range communication.
• Passive RFID: These systems have no in-built power source. It takes power from the reader and transmits the required data.

RFID for IoT Boards

The most common RFID receiver used for IoT projects is the RC522. This reader can be used along with a Raspberry Pi, Arduino, Node MCU or many other boards as well. It usually comes with 8 pins.

Applications

• Libraries: RFID tags are stuck to the books of a library containing data that is unique to that book. This data can then be used to track the book. This makes the process of borrowing books much more efficient.
• Animal Tracking: RFID tags are attached to domestic animals as well as farm animals to track their presence and their movement.
• Highway toll booths: RFID tags are stuck to cars where readers on the toll booths take payment information from these cars. They use this information to initiate transactions to automate the billing process.
• Attendance systems: Employees or students carry identity cards along with them that contain RFID tags. These tags contain information that uniquely identifies the owner of the card. Once the user scans their card against the reader, their attendance gets registered on a database.

There are hundreds if not thousands of other applications of this technology. This useful technology has become more or less ubiquitous hence it becomes important to understand how it works.

Conclusion

I hope this article has given a meaningful insight into how RFID works and how it is being used in the real world. If you have any queries, suggestions or comments you can leave it in the comment section below.

Happy Learning!! 😃