NFC Near Field Communication is one of the latest wireless communication technologies. As a short-range wireless connectivity technology, NFC offers safe — yet simple and intuitive — communication between electronic devices. Users of NFC-enabled devices can simply point or touch their devices to other NFC-enabled elements in the environment to communicate with them, making application and data usage easy and convenient.

With NFC technology, communication occurs when an NFC-compatible device is brought within a few centimeters of another NFC device or an NFC tag. The big advantage of the short transmission range is that it inhibits eavesdropping on NFC-enabled transactions. NFC technology opens up exciting new usage scenarios for mobile devices.

Near Field And Far Field

he terms “far field” and “near field” describe the fields around an antenna or, more generally, any electromagnetic-radiation source .The names imply that two regions with a boundary between them exist around an antenna. Actually, as many as three regions and two boundaries exist. These boundaries are not fixed in space. Instead, the boundaries move closer to or farther from an antenna, depending on both the radiation frequency and the amount of error an application can tolerate. To talk about these quantities, we need a way to describe these regions and boundaries.

• Like ISO 14443 , NFC communicates via magnetic field induction , where two loop antennas are located within each other's near field , effectively forming an air-core transformer . It operates within the globally available and unlicensed radio frequency ISM band of 13.56 MHz , with a bandwidth of almost 2 MHz.
• Working distance with compact standard antennas: up to 20 cm .
• Supported data rates: 106, 212, or 424 kbit/s .
• There are two modes:

Passive Communication Mode: The Initiator device provides a carrier field and the target device answers by modulating existing field. In this mode, the Target device may draw its operating power from the Initiator-provided electromagnetic field, thus making the Target device a transponder.