NFC, Unlikely

The most recent rumor is that this mysterious square chip (occluded by an EMI can) is an NFC combo controller and antenna, based purely on its square dimensions.

The NFC "chip" ensquared in red

Given the primarily metal backside of the new iPhone, it's highly unlikely that NFC is in the cards for this generation. In fact, given the very little space at top and bottom dedicated to those glass RF windows, you can almost entirely rule it out.

NFC operates on the 13.56MHz ISM band, which has a relatively large wavelength, at 22.1 m. Making a traditional dipole antenna that radiates at all given the constraints of a smartphone package is thus a big challenge, considering that smartphones are maybe 5-inches tall at maximum, to say nothing of the supposed upcoming iPhone's longest linear dimension.

From the NFC Forum Analog Specification

As a result almost all NFC antennas are big inductors and work using a magnetic field coupled between a host and peer device. Since we're talking about an inductor, NFC antennas use as big of a coil of wire as possible with as many wires as possible tightly wound together, and thus often use as big of an unbroken 2D plane as they can get on the device. In the smartphone space, basically all NFC antennas to date are simply flat spirals on a PCB. Whether this gets hidden on top of the battery like what Samsung has done in recent devices, or printed on the back battery cover like earlier devices, the antenna is ultimately a big square or circle with as big and dense of a coil as possible.

Galaxy Nexus Battery and NFC Antenna Coils (Courtesy iFixit)

Getting a good inductor into the device is important because how much inductance your antenna has will determine maximum coupling distance and ease of alignment. It shouldn't need saying, but having a huge ground plane (the unibody metal back case) in the way of your NFC antenna will seriously degrade performance, thus only the top or bottom windows are logical places to put it.

It's this last point which makes us very skeptical about the top or bottom RF windows being used for a relatively small NFC loop – not because such a thing is impossible – but rather because of how terrible the resulting ease of alignment and maximum coupling distance would be. Most NFC implementations at present place the inductive coils as near to the center of the device as possible, partly because this is the most optimal way to maximize the area which can be dedicated to it, partly because it makes alignment natural. With an NFC antenna at the extreme top or bottom, alignment with non-iPhones (for example, payment tokens or reader tags) becomes a much more confusing task, and that doesn't seem like the Apple-like level of polish everyone is waiting for to drive NFC adoption.

There's also a healthy number of signaling pins in the flex cable leaving the mystery chip, some of which appear to be signaling for the front facing camera which is part of the assembly, others for earpiece, proximity, and ambient light sensor. In addition this assembly also is obviously the assembled display and touch stack. When you consider the inclusion of in-cell touch sensing which has been rumored for the upcoming iPhone, and the requirement for time multiplexing of both display driving and touch sensing signals (to mitigate interference and make this possible), it's more likely that the components under that heavily shielded (and grounded with a big spring finger) EMI can are the touch and display controller combo that need to work in conjunction for in-cell to be possible.

The inclusion of Passbook in iOS 6 is the most often-cited piece of evidence for Apple including NFC, which seems a bit paradoxical since Apple hasn't disclosed at all whether it would favor NFC or a Bluetooth LE (low-energy) or even QR code based payment token through that gateway.

Cellular Connectivity: LTE Expected WiFi, Battery & Conclusions


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  • Super56K - Friday, August 31, 2012 - link

    jwcalla, you're (selectively?) forgetting the obvious: Apple is a major player that sells a ton of gadgets, but maintains a small product portfolio. Whether you want to see them fail or succeed, it brings in everyone. Want to kill the hype machine? Do your part and not click these articles or talk about it with others. Can't do that? Well, that's hype for you. Reply
  • Super56K - Friday, August 31, 2012 - link

    You are a sad individual. 1(!) current Apple article is too many for you? Really? Reply
  • Torrijos - Tuesday, August 28, 2012 - link

    While they're always nice to get a good result in some benchmarks I doubt their usefulness right now, even with Apple pushing an easy to implement concurrency/distribution model with Grand Central Dispatch most apps aren't going to benefit directly from quad cores CPU without further optimization.

    The type of apps that push the phones to their limits right now are games, and in that area Apple keeps providing very good GPU (still unbeaten in the tablet market).

    It would be pretty interesting to know the kind of influence network performance has on real life usage...
    While some web-centric benchmarks show quad cores outperforming old CPU badly, would those benefits disappear when browsing in a slow area connection? At what effective bandwidth is the new CPU unable to provide better global performance?
    This could be tested by limiting your server upload bandwidth on the wifi, to simulated a non-optimal connection area.
  • versesuvius - Tuesday, August 28, 2012 - link

    No matter which theft of ideas, apple manages to turn into glossy status symbols, no one should buy any iSh.. anymore. iSh.. has turned into a symbol of stupidity and greed all over the world.

    Just as brandishing an Apple product would say something, now owning a non iSh... makes the same statement quite forcefully.

    Sh.. yourself none. Don't buy iSh..!
  • A5 - Tuesday, August 28, 2012 - link

    Oh man, you're so clever! You really convinced everyone with that amazing argument! Thanks! Reply
  • versesuvius - Tuesday, August 28, 2012 - link

    Thank you, very much! I know I am happy with no iSh.. polluting my environment. Your environment is up to you, which is painfully obvious anyway. Reply
  • swb311 - Tuesday, August 28, 2012 - link

    Who let you onto the internet? Reply
  • versesuvius - Tuesday, August 28, 2012 - link

    I assure you that I was here before you were born. I read Anand's first article(s) on a 5.6 kbps dial up modem. I know what I am talking about. Shed the iSh.. . It is that time of the day! Reply
  • KoolAidMan1 - Tuesday, August 28, 2012 - link

    I see, so you're old AND stupid. Fantastic :) Reply
  • versesuvius - Tuesday, August 28, 2012 - link

    Yeah, just like your parents.

    Youth is a gift that you obviously do not deserve. It is good to see that it is wasted on iSh..!

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