What is NFC?
NFC stands for Near Field Communication. It uses electromagnetic
radio fields to allow two compatible devices to exchange data. It's not a new
concept, and the Japanese have been using it extensively over the past decade.
Thanks to Google (Android), phone manufacturers, and other wireless tech
companies, it's starting to gain footing in the US market. This short range,
wireless standard is an enhanced version of RFID technology used in one way
communication devices, such as contactless bank cards, which allows two devices
in close proximity to talk to each other. Basically, put two NFC devices close
to each other, and they exchange information and commands immediately.
(NFC Logo Credit: NFC-Forum.org)
How Does it Work?
NFC
operates at 13.56 MHz at rates ranging from 106 kbit/s to 424 kbit/s. NFC technology
can be broken up into 3 categories: Signal Technologies, Tag
Types, and Modes of Operation. There are three different RFID Signal Technologies that exist to make NFC
devices talk to each other.
NFC-A uses Miller
encoding, also known as delay encoding, which registers 1s and 0s as a change
from 0 to 100% amplitude modulation and 100 to 0% percent modulation
respectively.
NFC-B similarly uses a change in
modulation percentage to register a 1 or a 0. In this case, amplitude
modulation is at 10 percent, meaning a 10 percent change from 90% for low,
to 100% for high, is used. As opposed to NFC-A, a
change from low to high represents a 0, while high to low represents a 1.
NFC-F is a passive contactless payment
system referring to FeliCa, short for Felicity Card. Commonly found in Japan, this encrypted signal is a faster
form of RFID transmission and is currently the most popular form used for a
variety of services such as subway tickets, credit card payments, and identification.
Tag Types. In addition to the signaling
technologies, there are four Tag Types. These refer to the speed and
compatibility between an NFC tag and an NFC reader. Some NFC tags only contain
a URL, for example, and don't take up much memory at all. This allows for cheap
production of NFC tags that can be placed on posters
or other things that will probably just e nd up getting thrown away when a promotion or advertisement is over. These would include Tag Types 1 and 2. Tag Type 3 has larger memory and faster speeds than 1 or 2, but
costs more to produce. Type 3 Tags are used with NFC-F. Type 4 Tags use NFC-A or B, and can be set as either rewritable or
read-only from the factory. They hold 32 Kbytes of memory and are the fastest
tags available. (Clear NFC Tag Courtesy of http://creativecommons.org/licenses/by-nc-sa/3.0/)
Modes of Operation. This is where it gets fun. There are two sets of
active/passive roles, or modes of operation. One is the transaction between readers/writers and an NFC card. Typically a transaction occurs
between an active device that sends signals out and receives information back,
and a passive device that simply sends the information and doesn't care about
anything else other than what it's told to reply with. For example, the
reader/writer here would be a smartphone and the passive device would be an NFC
tag. The beauty of NFC and smart phones is that the phone can also take on the
role of a card and act as a credit card for contactless payments. So the credit
card reader then becomes the reader/writer and the smartphone is the passive
device. To see my example of NFC working for me, jump to stay tuned for Part II - Example of its Power.
Finally,
the other mode of operation is initiator and target. NFC holds an advantage
over other technologies such as RFID for this reason. Using this mode, NFC can
create peer-to-peer sharing between phones. The phone making a connection or sending
the invitation would be the initiator and the phone receiving the data is the
target. Both phones can serve both roles and switch back and forth.
Breakdown of NFC Technology
What Are the
Benefits?
As with anything running on your
mobile device, power consumption is a top concern. Thankfully, the NFC initiator
(smartphone) uses less than 15 mA while reading, and much less than that while
in an idle, ready-to-read state. Plus, all NFC enabled Android handsets are
programmed to run the NFC radio only when the screen is on. So all in all,
power consumption is negligible. Many people believe that turning off this
option on an NFC enable phone will conserve battery life. Technically this is
true, but again it only polls when the screen is on and the power consumed is
so minimal, you'd hardly notice either way.
So what is the
benefit when compared to existing wireless protocols such as WiFi or Bluetooth?
Besides NFC using drastically less power, it establishes a connection instantly
(less than a 10th of a second). The ability to establish a data
connection without an IP address, without passwords, without pairing, without
even looking at the device - just a simple wave or tap on its target -
basically turns your phone into a
magic wand, automating every day repetitive tasks with a simple motion. And, to
me, it's just cool to pay for a soda by pulling out your phone, tapping the
reader at checkout, and walking away.
NFC serves as the backbone for current
and planned mobile wallet systems, but it can be used for much more than commerce.
Other uses include quickly tossing your schedules, maps, links, business cards,
images, and other information in one simple tap to another NFC device such as a
friend or business partner's phone. It can be used to bootstrap another
wireless connection such as connecting to a WiFi network or pairing a Bluetooth
connection. Social networking, keycards, the list can go on - we'll get to the
practicality soon in Part II - Example
of its Power, so sit tight. But in order to enjoy the benefits, you must have an NFC
enabled phone. Click here to
find a list of current NFC enabled phones.
If you have an
NFC phone and you're lucky enough to
have Google
Wallet support, be sure to download the app and get a free $10 wallet
credit upon installation that can be used for anything.
Now
that you're an expert in NFC technology, let's use it to make our lives easier! Next week, in Part II, I will show you how to set up an NFC enabled
Android phone (Samsung Galaxy Nexus) to automatically start playing music when
you get in your car. You may ask, "Is that really necessary?" No, not
really. Well,
you decide. Consider this: Many use WiFi at home, and then switch to 3G/4G when
they go out. Switching WiFi off when not in use helps
battery life. Many keep Bluetooth switched off for the same reason. So if
your routine is similar to mine, you would get in the car, turn off WiFi, turn
on Bluetooth, open the media player, choose an album, press play, and put the
phone away. Assume it takes you 10 seconds to do this. If you wish to have
music every time you drive, let's say minimum of twice daily (daily commute,
weekend activity), you would spend 20 seconds every day performing a mundane
task. That may not seem like much, but over the course of a year you wasted a minimum of
2 hours doing nothing but essentially turning on
and off a switch. The more manual tasks you let NFC tags handle, the more time
you save.
How Can I Get Started?
You'll need
some tags: I recommend Tag
Stand's Starter Kit. They also provide tags that can adhere to and work on metal
surfaces, and outdoor
rated. One thing to note is that if you're running Android 4.0.2 or lower,
you need to add a comment on your order requesting that they preformat your
tags, since there's a bug in < 4.0.3 that won't let the phone format tags.
If you're on 4.0.3 or higher, nothing to worry about; they'll work out of the
box.
You'll
also need a reader/writer: NFC
Task Launcher, or Tag
Writer. That's basically all you need to get started. The only limit to
what you can do with NFC is your imagination. Let's get some ideas flowing then,
shall we?
Ideas for Implementation
·
Make your phone quiet and peaceful for bed
time
·
Toggle GPS, radios, and launch apps
·
Unlock your front door
· Traditional keyboards too convenient for you?
How about the headache-inducing NFC keyboard?
· Control your whole house!
·
Spend a lot of time in the kitchen? Slap a tag
onto your stove or fridge to launch a pre-set timer for your pizza!
I'm far from the most creative
person in the world, so I'd love to hear some ideas from the engineers on CR4!
How do you think we could use NFC or NFC Tags to make our lives simpler or
automate repetitive, everyday tasks?
Sources:
Near Field Communication
Contactless Smart Card
NFC Forum
NFC Org
APC Inside NFC: how near field communication works
Charge Smart Blog What is 'NFC' Technology?
PCWorld 10 Ways to Boost Your Smartphone's Battery Life
Android Police Fun With NFC
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