NFC and RFID Systems: What Are They and How Do We Use Them?
Andrew Solovev
Chief Technology Officer – Integra Sources | PhD in Physics and Mathematics | Turnkey IoT solutions | Electronics design | Embedded systems | Power electronics
RFID and NFC technologies are used in many different industries. Their most common applications are asset tracking and contactless payment, but they are used in other spheres as well.?
RFID & NFC Systems
RFID (radio-frequency identification) is a wireless communication technology that can uniquely identify objects with radio waves. RFID systems use readers and tags placed on items. Their work is similar to that of optical scanners and barcodes. The tag contains information about the item. When the reader sends an interrogating signal to the tag, it activates and sends back the ID information. The reader displays the data and can also transmit it to a database.
NFC (near field communication) is a similar wireless communication technology that evolved from radio-frequency identification. But unlike RFID devices, NFC systems are rather magnetic transmitters than radio transmitters. They use alternating magnetic fields and operate at the frequency of 13.56 MHz.?
Differences
Near field communication devices have a very limited operating range – only a few centimeters. Also, the tag must be in the line of sight of the reader to respond.
RFID systems have a longer operating range. Civil devices can reach about 3-5 m. Some systems can reach dozens of meters. Additionally, RFID readers do not need tags to be in their line of sight.
RFID systems are only capable of one-way communication. The tag sends the data to the reader but not vice versa. However, NFC systems are capable of two-way communication. Two devices can function as a reader and a tag by turns.
Near field communication is relatively slow. Its data transfer speed does not exceed 424 kbit/s. Also, NFC readers can only scan one tag at a time. Radio-frequency identification can transfer data faster and read multiple tags at a time.?
RFID tags can contain only simple ID data. NFC tags can store more information and support different data types.?
Applications of NFC and RFID Systems
The ability to read ID information from a short distance allows radio-frequency devices to be commonly used for the following tasks: access control, real time location systems, logistics and supply chains, inventory tracking and management, animal tracking, marketing, vehicle access, theft prevention, and race timing.
Although near field communication systems have a shorter range, they find various applications as well. Sometimes, both these technologies can perform very similar or identical tasks. NFC systems are used in contactless payments, data exchange, access control, healthcare, smart ticketing, manufacturing and logistics, marketing, and other spheres.
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These are the most common applications of RFID and NFC devices. Businesses also find unexpected ways to benefit from these technologies. Such systems are used for tracking paper documents and luggage at airports. In some casinos, chips have miniature tags to prevent thefts and track visitors’ behavior. Other tags allow people to track their pets or learn more information about products in supermarkets. The applications of NFC and RFID systems are very versatile.?
NFC and RFID Alternatives
As I mentioned above, NFC and RFID systems can be regarded as high-tech alternatives to barcodes when it comes to inventory tracking and management. The same goes for QR codes. These alternatives are cheaper but have a number of disadvantages. Barcodes and QR codes must be in the line of sight of the optical reader to work. Also, they deteriorate with time.
Another RFID and NFC alternative is to use wired ID chips for identifying items. But in this case, direct contact is required.
Sometimes, Wi-Fi, BLE, Zigbee, and Z-Wave can serve as alternatives to RFID and NFC systems in location tracking systems. These technologies have a longer operating range but require energy. Unlike them, passive RFID tags don’t require a power supply. Besides, creating infrastructure for such systems can be quite expensive.
Using Wi-Fi, BLE, Zigbee, and Z-Wave for the tasks typical for NFC and RFID is rather exotic. Still, in certain circumstances, it can be reasonable.?
Certifying RFID and NFC Devices
Since RFID and NFC systems use radio waves, they can cause electromagnetic interference. This is why new devices based on these technologies usually must comply with the FCC (for the US market) and the CE requirements (for the EU market). RFID and NFC-enabled systems may also require such certifications as UL (may be required by retailers), California Proposition 65, ATEX, IECEx, IP, IK, ARC, and more.
Note that the frequency ranges allowed to be used by short-range transmitters differ from country to country. For instance, in the US, ultra high frequency RFID systems are allowed to use 902-928 MHz. The same systems in Europe are only allowed to use 865-868 MHz.
The Cost of NFC and RFID Systems
When it comes to RFID or NFC development cost, it is defined by multiple factors. The most crucial of them is usually the size and complexity of the system. Another important thing is whether the team can use off-the-shelf components or needs to develop them from scratch. If the system is supposed to work in an extreme environment, the casing can get expensive too. And of course, regional prices vary a lot as well.
The following description is a very rough estimation of how much the device under development can cost. The price does not include NFC or RFID firmware and software development.
Simple devices that don’t use a computing system can cost about $4 each (if we use off-the-shelf components) or about $3 (if we design an original model).
If the device uses a computing system (a microprocessor or a microcontroller), an off-the-shelf alternative can cost about $26. An original device with a dynamic RFID/NFC tag will be cheaper – about $9.
If the system doesn’t have special requirements related to the microcontroller, it is reasonable to use a microcontroller with an integrated RFID/NFC interface. In this case, each device will cost about $17.
Read the original article on RFID and NFC systems on our blog to learn more details. There you can also read about some interesting projects that involve RFID and NFC technologies.