We are surrounded by wireless networks. Some are very small and are called “tiny area networks”. One of the smallest of these is Near Field Communications or NFC.

Near Field Communications has a range of about one inch, so it is a proximity network. NFC uses many of the same standards and technologies developed for Radio Frequency Identification or RFID. The main difference is that RFID is one-way, NFC is two-way. NFC also uses much less power.

NFC has two popular modes of operation. One is “card emulation” which is used for things like contactless payment. This happens when you “tap and pay”. The other mode is “peer to peer” which is used for communications between two NFC devices. For example, this is used for transferring material between two smart phones in close proximity.

NFC uses two kinds of hardware. The NFC reader initializes and controls communication. It contains a small electromagnetic transceiver normally operating on 13.56 MHz. NFC readers interact with devices that contain NFC tags. There are many different kinds of tags, but basically they contain an antenna and a data transport protocol chip. These tags can be passive, and simply communicate by modifying the electromagnetic wave sent by the reader.

Near Field Communications Tags and Taps

NFC tags are so small and either need no power or very little. You can put them in almost anything. Just like the library puts RFID tags in its books to automate checkout.

The cost of microchip and antenna NFC tags will probably come down from 30-50 cents to under 10 cents this year. But this is  expensive compared to an RFID tag at five cents or the ink in a bar code at less than a penny. On the other hand, smart systems using two-way NFC could result in lower total operating costs than bar codes. So I think there is a big path ahead for Near Field Communications.