Near Field Communication
If you’ve checked out the hardware specifications for a high end smartphone
or digital camera lately, odds are that you’ve seen NFC listed on the specifications. But despite the time NFC has been around, it has not yet become the standard for all
digital devices. If you’re satisfied with an older phone, or can’t quite rationalize springing for the latest top of the line version, you may be wondering what all the ruckus is about. So here’s a sketch of what NFC is all about, how it works, and what you can use it for.
NFC is an acronym for “Near Field Communication” and, as the label implies, it implements short range communication between harmonious devices. This requires a minimum of one transmitting device, and another device to receive the signal. An array of devices may use the NFC standard and can be treated as either passive or active, depending on the way the device operates.
Active components have the ability to both send and receive data, and can also communicate with one another as well as interact with passive devices. Smartphones and cameras are by far the most prevalent implementation of active NFC devices, although public transport card readers along with touch payment terminals are also prime examples of the technology.
Passive NFC components encompass tags, and other small transmitters, that can transmit information to other NFC devices without needing a power source of their own. However, they do not really process any information obtained from other sources, and cannot connect to other passive devices. These are often seen in the form of interactive wall signs or advertisements.
How it works
Similar to Bluetooth and Wi-Fi, and all aspect of other wireless signals, NFC operates on the principle of transmitting information using radio waves. Near Field Communication is one more standard for wireless data transitions, which means that there are specifications which devices must adhere to in order to properly communicate with one another. The technology used in NFC is based upon older RFID (Radio-frequency identification) concepts, which use electromagnetic induction as a way to transmit information
This marks the one considerable difference from NFC and Bluetooth/WiFi, as it can be employed to bring about electric currents within passive devices as well as only send data. This allows for passive components to not require their own power supply, and instead can be powered by the electromagnetic field created by an active NFC device when it comes into range. Unfortunately, though, NFC technology does not create enough inductance to be used to charge cameras and smartphones, however QI charging is based upon the same principle.
In order to determine the kind of information is to be exchanged between components, the NFC standard currently has three distinct operation modes for devices to be compliant. Perhaps the most typical use is in smartphones with the peer-to-peer mode, which allows two NFC-enabled components to exchange
separate pieces of information between one another. In this mode both components switch between active, when sending and to passive states when receiving data.
On the other hand, read/write mode, one way data transmission, where the active component, possibly your smartphone, links up with another device as a way to read information from it. This is the approach used when you unite with an NFC advert tag.
The last operation mode is card emulation, where the NFC device can be employed like a smart or contactless credit card as a way to make payments or connect to public transport systems.
You might believe that NFC isn't even necessary, considering that Bluetooth has been more extensively available for several years. However, there are considerable important technological distinctions between them that gives NFC some significant advantages in certain circumstances.
The major case in favor of NFC is that it has much less power consumption than Bluetooth, even less than the newest Bluetooth 4.0 (aka Bluetooth low energy). This gives NFC an advantage for passive components, such as the advertising tags mentioned above, as they can operate without the major power source requirements.
However, this power saving does have a few major shortcomings. Most apparent is that the transmission range is much less than Bluetooth. While NFC has a range of about 10cm, only a few inches, Bluetooth can transmit data as far asquite10 meters or more from its base. Another drawback is that NFC is much slower than Bluetooth, transmitting data at a top speed of just 424 kbit/s, contrasted with 2.1 Mbit/s for Bluetooth 2.1 or approximately 1 Mbit/s with Bluetooth Low Energy.
Although NFC does have one distinct advantage of faster connectivity when it comes to speed, Because it uses inductive coupling, along with the absence of manual pairing, it only takes less than a tenth of a second to create a connection between a pair of devices, a speed which has only lately been equaled by Bluetooth 4.0.
Galaxy Nexus Google Wallet
Perhaps you have noticed that NFC with Android Beam, or S Beam on
Samsung’s Galaxy smartphones, actually uses Bluetooth or WiFi Direct for sharing information between components. These two technologies really only use NFC to quickly connect the two devices with each other. This combination of wireless standards provides for maximal wireless transfer speeds, but without the longer times to connect associated with Bluetooth.
A Future Standard
With the expansion of interactive advertising, contactless payment arrangements, and the establishment of services like Google Wallet, NFC is the wireless standard best positioned to make our smartphones a
feasible alternative to credit and transport cards.
Already, there are over 300,000 MasterCard PayPass merchant located in the United States but there is still some way to go before NFC acceptance rates are large enough for these technologies to become feasible on a mass scale. But when more budget and midrange smartphones start selling with NFC aboard, this could may just be the way that many of us pay for our goods and services in the future.
March 26, 2016