September 14, 2004

Wireless Gets Up Close

Wireless transmissions that travel only a few centimeters may be just the ticket for embedding cell phones with smart-card technology.

By Eric S. Brown

When comparing wireless transmission range, longer is almost always better. Yet the developers of a new technology called Near Field Communications, or NFC, boast not about how long a distance it works over, but how short.

With a range of just 10 centimeters, NFC can get by with a very small, low-cost radio transmitter that draws only a pittance of power. Its very feebleness of transmission helps to ensure security. Forget about a hacker snooping on your Wi-Fi session from a laptop outside the buildingwith NFC, even a colleague sitting next to you at a meeting may be too far away to sniff the signal. Yet if you do want to swap data and move your NFC device next to hers, the connection is immediate. What's more, you can take the same device down the hall and use it to buy a soda from a vending machine. These attributes were enough to convince Nokia, and as of August 30, Samsung, to announce that their next-generation cell phones will come equipped with NFC chips. Nokia's NFC-enabled handsets are promised by the end of the year.

For handset vendors, NFC represents a low-cost entry into the smart card market. Cell phone users could potentially use their phones as contactless smart cards for electronic turnstiles, event ticketing, and even checking out at the supermarket. The technology would also let users display images from a digital camera phone on a nearby TV, graze promotional offers from subway billboards, or swap contact information between devices. And with the help of Philips and Sony, the two consumer electronics giants that jointly developed the technology, the low-cost radio chips could appear in everything from TVs to PCs to digital cameras. The market research firm ABI Research predicts that by 2009, NFC-enabled products will account for half the cellular handset market.

Near Field Communications adheres to a standard ratified last year that specifies transfer speeds up to 424 kilobits per second operating at a frequency of 13.56 megahertz. (Early NFC devices will be limited to half that speed.) NFC offers a much shorter range than the radio frequency identification (RFID) technology on which the new standard is based: 10 centimeters instead of 2 to 5 meters. But like RFID, NFC transmits information via inductive electromagnetic coupling in the radio frequency portion of the spectrum.

The key difference is that NFC adds software that enables instant setup of peer-to-peer networking. As with P2P wireless communications between Bluetooth- or ZigBee-enabled devices, NFC devices automatically seek each other out and establish a communications link. (The popular Wi-Fi wireless networking technology is different, as it requires an access hub.) This P2P approach also differs from RFID networks, which are set up in a master/slave relationship in which passive chips are read by expensive, powered reader devices. NFC devices, on the other hand, can be set to either passive or active mode, so they can send identification data even when the device is turned off (passive mode), making it ideal for smart card applications. At the same time it is also capable of playing the active role, orchestrating communications with other active or passive RFID-based devices.

The key advantage of NFC (aside from its low cost) is the speed with which you can initiate a communications session. NFC has very fast and easy configuration and pairing, says Tariq Shahab, Philips Americas Contactless Identification Business Development Manager. By comparison, Bluetooth, which is also designed to exchange data between devices in close proximity, requires tedious setup procedures between communicating devices. To use Bluetooth with different devices, you have to go through a lot of configuration, but with NFC its just touch and go, Shahab says. Due to this instant connection capability, NFC is being pitched as a kind of virtual connector that can act as a lingua franca for setting up sessions using other, more powerful, wireless technologies such as Bluetooth and Wi-Fi. In other words, devices could first introduce themselves via NFC before moving to a faster, longer-range medium.