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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  • KoolAidMan1 - Tuesday, August 28, 2012 - link

    Unless you're a Linux using neckbeard (and I'd bet money that you aren't), then your entire post is trash.

    And if you are a Linux using neckbeard, sucks to be you
    Reply
  • Focher - Tuesday, August 28, 2012 - link

    Funny that each generation of iPhone is just an upgrade to all the previous generation iPhone owners. Of course, we wouldn't want math to get in the way of that assertion so let's just assume every iPhone owner will buy at least two of the next version. Some even more!

    Also interesting is your claim that the article is based on conjecture after two whole paragraphs of exactly that which you disdain. By the way, I would suggest you look up that word in a dictionary. Because an article that analyzes leaked pictures of the hardware and then makes predictions based on those items doesn't at all fit the definition of that word.
    Reply
  • inplainview - Wednesday, August 29, 2012 - link

    Obviously someone has given you the impression that your purchasing decisions matter to the masses. No one really cares what you will and will not buy. Reply
  • Super56K - Friday, August 31, 2012 - link

    I love these posts. It gives the vibe of someone standing on a street corner holding a 'THE WORLD IS ENDING' sign; giving the same spiel, over and over, to anyone who makes eye contact. Reply
  • solipsism - Tuesday, August 28, 2012 - link

    If by tweak, you mean completely redesigned, then yeah. Reply
  • ramnam - Monday, August 27, 2012 - link

    Would using a backplate made of the liquidmetal stuff mitigate concerns about it acting as a ground for the NFC field ? I understand Apple licensed the technology a while back Reply
  • jrswizzle - Tuesday, August 28, 2012 - link

    This is an on-again, off-again rumor I hope comes to pass. Though the head of the company who produces the liquid metal said it would be years before they'd be able to produce the stuff on the mass scale needed for a device like the iPhone to be made of it. Reply
  • swb311 - Tuesday, August 28, 2012 - link

    Several years away unfortunately Reply
  • jwcalla - Monday, August 27, 2012 - link

    If true it's a rather conservative update at a time when the competition is getting pretty fierce. You can't be too risk-averse in this business. Reply
  • jjj - Monday, August 27, 2012 - link

    there is a bigger screen there so battery life might not be any better.
    as for the SoC,they mgiht go for dual A9 (they certainly won't go quad) but that's so far behind the top phones that they really should do more.
    The iPhone is the new dumbphone but still quad Krait vs dual A9, is just lol.
    Reply

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