NFC or Near-Field Communications is a rapidly growing wireless, short-range technology. Approved as an ISO standard in 2003, NFC is a form of RFID technology that has a read range of up to a few centimeters. The ISO standards approved by the International Organization of Standardization (ISO 14443 and ISO 18000-3) exist on the HF or High-Frequency band on the Radio Frequency Spectrum.
Since its inception, NFC has grown in popularity due to widespread adoption in response to NFC’s fast connectivity and data transmission capabilities. Below are some little known facts about NFC as well as unique applications for the technology.
Facts
1. Types of NFC Devices
There are two main types of NFC devices: Passive communication NFC devices and active communication NFC devices. Passive devices have no power source and can only connect to active devices. Active devices have a power source and can send and receive data by switching between the normal active (transmitting) state and a passive (receiving) state. In a typical NFC system, there is an active NFC device, passive NFC device, and a host computer or application. Unlike a UHF RFID system that requires both a reader and a tag, active NFC devices can communicate with other active NFC devices by switching between the active state and the passive state. An example of this is using NFC devices or smartphones for the exchange of data.
2. Magnetic Coupling
NFC technology uses magnetic coupling to send and receive signals. When two NFC enabled devices are close enough (from touch to 10 cm), they create an electromagnetic field between them. That electromagnetic field allows the active NFC device to power up and communicate with the passive NFC device. The active NFC device then picks up on variations in signal levels specific to the passive device and reads those variations as a signal. A detector and decoder circuit in the active NFC device is then used to comprehend the passive NFC signal and extract the relevant information. The host computer or application can then understand the information and take any relevant next steps.
3. Modes of Operation
Three main modes of operation for NFC devices are:
Peer-to-peer mode – Active NFC devices exchange information by switching between passive and active states.
Read/write mode – Active NFC device reads or writes information from/on a passive NFC device.
Card emulation – An Active NFC device used for contactless payment.
4. Read Range
The optimal read range for NFC tags is between 1 cm and 10 cm due to the need to form a magnetic field.
5. Security Risks
Security risks exist when using NFC technology as a payment form. Since all the parts in an NFC system needs to be within 10 cm to enable the technology to transfer the data, eavesdropping with another NFC device is fairly difficult without being noticed, but can be done.
There are other, more complex ways that thieves are trying to steal NFC data through data corruption, interception devices, or just theft of the NFC device. While new ways are coming out to try and defeat NFC security, new security measures are being put in place.
6. Form Factor
The typical NFC tag has a relatively small form factor, but the size is dependent on the size of the antenna. Tags vary in sizes from a couple inches in length and width to only a few centimeters. NFC reader devices are usually smaller devices that mimic the size and shape of a typical smartphone.
7. Availability
NFC is currently available in most Android devices and in Apple iPhones versions 6 and up. While Android and other NFC enabled phones have an unlocked NFC device, Apple so far has only enabled the use of NFC on their devices for Apple Pay. There are also other NFC reader devices on the market that specialize only in NFC reading and writing.
Applications
NFC technology is typically used for payments and marketing applications today, but many other applications are slowly adopting NFC. Because programming is usually needed to bridge the gap between reading the tag and any action items associated, there are a few apps available to make some of these NFC uses come true. Below are a few examples of creative ways to use NFC tags.
NFC can provide a phone with the ability to change settings depending on what tag is tapped. Placing a passive NFC tag on a desk at work and tapping it with an active NFC smartphone can (with the help of the right app) turn Wi-Fi on, Bluetooth off, or turn the ringer volume down.
Other abilities include setting timers, calling specific contacts, saving battery power, or opening apps. To read more about these clever applications check out NXP’s 20 Creative Uses for NFC Technology and CNET’s Practical and Creative Ways to Use NFC.
From：http://blog.atlasrfidstore.com/
