What is RFID?
RFID is a radio frequency identification technology. This technology provides the ability to detect, read, record and interact with information stored in a tag using radio waves. For this purpose, tag readers and tags don't necessarily need a direct line of sight to each other, which makes it much easier to use RFID technology.
RFID system components
As you may have noticed, a basic RFID system consists of two main components: a tag and a tag-reader system. Now let's examine each of these sections separately.
An RFID tag contains a transceiver that communicates with the tag reader and interacts with it based on the tag structure. Tags are divided into two main active and passive categories:
- Active tags need to be powered by an external source, or from a built-in battery. Because this type of tag is bulkier than its passive partner, it is used in certain applications and is not widely seen in the retail industry.
- Passive labels use radio waves transmitted by the reader to supply their energy. These tags can be tiny and therefore have an extensive range of applications.
The internal structure of the tags consists of two main parts, an integrated circuit that is responsible for storing and processing the intended information, and an antenna that is used to receive and send the signal. The RFID tag also contains a non-volatile memory portion that can be read-only or writeable.
The tag reader system is also a radio transmitter/receiver that transmits radio waves to activate the tag. Then, the tag transmits its stored information is received by this device and be relayed to the information processing system.
Types of RFID systems
RFID systems are divided into three categories according to the type of radio frequency used:
- RFID systems with low frequency: These systems operate at a frequency between 30 to 500 kHz. These systems, known as LF RFIDs, have a limited range, usually between a few centimeters to a distance of less than one meter.
- RFID systems with high frequency: The radio frequency used by these systems is between 3 and 30 MHz, and their range is less than 2 meters. The use of the 13.56 MHz frequency is common in these systems that known as HF RFIDs.
- Ultra-high frequency RFID systems: UHF RFID systems with a frequency range of 300 MHz up to 960 MHz. The range of these systems is more than 8 meters.
RFID features allow it to have interesting applications. For example, today when you go to a large store, you must go to the POS after choosing the goods you want, so that the operator checks each bundle of your items with a barcode reader and issues the final bills. Now if there was an RFID system in this store, you just needed to pass your shopping cart from a reader's machine to get your bills immediately.
RFID is also used to track and manage various items. Processes such as customs clearance, inventory, sales, and surveys are only a limited number of RFID applications. The most interesting point is that RFID provides these capabilities with the least cost possible for the managers.
The practical freedom offered by RFID allows for the definition of highly innovative applications. For example, suppose a manufacturer supplies a particular item at an airport. By installing RFID tags as well as tag reader systems at airport entrances and exits, the manufacturer can find out that its products are bought by entering passengers or outgoing passengers, without inconvenience to the passengers or possibly direct examination.
Also, in some countries, plans were made to track the sale of various goods to collect information like in what parts of the country or in which districts a particular product has more sales rate. But most of these plans were strongly opposed by privacy advocates who believed that such information was considered to be entirely personal.
However, RFID applications in various domains are still expanding, and now, with the development of the concept of the Internet of Things, we see the presence of this technology in the IoT industry.