Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!

 



Forgot your password?
typodupeerror
×
Iphone Apple

Experts Explain iPhone 4 Antenna Problem 427

CWmike writes "Reports of call and data signal strength problems in the new iPhone 4 have a basis in fact, a hardware expert said Thursday. Later in the day, Apple acknowledged that holding the iPhone 4 may result in a diminished signal that could make it difficult to make and maintain calls or retain a data connection. 'Gripping any phone will result in some attenuation of its antenna performance with certain places being worse than others depending on the placement of the antennas. This is a fact of life for every wireless phone,' Apple said in a statement issued to several media outlets, including PC Magazine, which had run tests earlier Thursday. 'If you ever experience this on your iPhone 4, avoid gripping it in the lower left corner in a way that covers both sides of the black strip in the metal band, or simply use one of many available cases.' Scores of new iPhone owners confirmed the reception problem in a string of more than 360 messages posted to a thread on Apple's iPhone 4 support forum." A blog post from an antenna design company explains that the reception problems are probably the direct result of phone design adapting to FCC requirements.
This discussion has been archived. No new comments can be posted.

Experts Explain iPhone 4 Antenna Problem

Comments Filter:
  • by plover ( 150551 ) * on Friday June 25, 2010 @05:09PM (#32697270) Homepage Journal

    Next thing you know, holding a cell phone with the thumb and forefinger by the top right corner will become the fashionable way for any of the cognoscenti to hold their phones. Those of us who cradle them in the old fashioned way will be "not of the Body of Jobs", and mocked and ostracized.

    • by Anonymous Coward on Friday June 25, 2010 @05:13PM (#32697314)

      Sorry, but there is only one correct way [imageshack.us] to hold a phone

    • by Idbar ( 1034346 )
      You need to stop criticizing already! These are magical devices [youtube.com] and need to be properly held [moviesonline.ca].
    • Sorry, your vulcan grip has been obsoleted by the new iPhone grip.
    • Re:Cue the fanbois (Score:5, Interesting)

      by PolygamousRanchKid ( 1290638 ) on Friday June 25, 2010 @05:29PM (#32697498)

      Next thing you know, holding a cell phone with the thumb and forefinger by the top right corner will become the fashionable way for any of the cognoscenti to hold their phones.

      So how come this problem was not identified during the system test of the device? Were all the testers instructed to hold it that way? Or maybe they identified it, but did not have the courage to report it?

      • Re:Cue the fanbois (Score:5, Insightful)

        by LBArrettAnderson ( 655246 ) on Friday June 25, 2010 @05:46PM (#32697692)

        In a sane world there's no way that my theory can be right, but here it is:
         
        The lab tests were done at Apple HQ, where AT&T has a tower in order to keep Steve Jobs happy -- plenty of signal even with the defect. The field tests were done with the rubber disguises on, so it didn't affect them.

        • Re:Cue the fanbois (Score:5, Insightful)

          by StikyPad ( 445176 ) on Friday June 25, 2010 @06:04PM (#32697896) Homepage

          Grounding, or effectively grounding (by say, shorting two ends of a dipole) an antenna will *always* result in loss of signal, even when starting values are ideal. But regardless of how it was missed, the fact that it was missed at all means one thing: inadequate testing.

          • Re:Cue the fanbois (Score:5, Insightful)

            by Pojut ( 1027544 ) on Friday June 25, 2010 @06:18PM (#32698060) Homepage

            Grounding, or effectively grounding (by say, shorting two ends of a dipole) an antenna will *always* result in loss of signal, even when starting values are ideal.

            I think the bigger problem is that with all of Apple's "expertise with hardware", they would design something with this kind of flaw.

          • Re:Cue the fanbois (Score:5, Interesting)

            by Dahamma ( 304068 ) on Friday June 25, 2010 @07:51PM (#32698792)

            Luckily the human body is a pretty poor conductor, as long as you are not standing in the shower (which I believe would be a bad place to talk on the phone anyway).

            I can say from first hand testing that the initial quality of the signal has a lot to do with the attenuation caused by this issue - if you already have a good signal it doesn't seem to cause any problems.

            Anyway, as you said, the fact that this was missed is pretty amazingly bad testing, especially considering how Jobs actually described in the keynote that the reason the metal on the outer rim had a visible break was because it acted as an antenna. Wouldn't you think the *first* question one would ask as a tester (or an engineer!) is "hmm, these are not connected for a reason - I wonder what happens when I connect them with various common household objects, like, say - my HAND?"

          • Re:Cue the fanbois (Score:4, Insightful)

            by PPalmgren ( 1009823 ) on Friday June 25, 2010 @10:03PM (#32699552)

            I'm curious who they are employing to design this stuff. I learned about this crap in EE 102, my first year of college. Also, if they had anyone with long-term experience in the company, they'd remember what happened with early 90's cell phones with the retractable antenna.

            I honestly think that there's a case here of someone without knowledge in middle management overriding engineer's recommendations.

        • by symbolic ( 11752 ) on Friday June 25, 2010 @11:09PM (#32699880)

          I don't think this was missed at all. It's like any of the other "defects" that have showed up in Apple products. I'm tempted to believe that Apple knew quite well about this, but decided to go with it anyway because a) fixing it would involve removing some of the "sleek" factor and b) they knew that there would be such mass hysteria over acquiring the new product that it wouldn't matter - at first. It's all about taking calculated risks.

          That having been said, it's precisely this attitude that destroyed my fan loyalty several years ago- I simply got tired of being bent over by Apple's marketing prowess. I still buy an Apple product every now and then, but the days of drooling all over myself at the mere mention of a new Apple product are LONG gone.

          • by sqrt(2) ( 786011 ) on Saturday June 26, 2010 @03:15AM (#32700784) Journal

            I'm pretty sure that's why they designed the bumper accessories to be the way they are. They turned a product defect into a way to sell an overpriced accessory to fix their devices shortcomings - and it's working! The Jobsian management style never ceases to amaze me with its outcomes.

      • It may have been (Score:4, Interesting)

        by Sycraft-fu ( 314770 ) on Friday June 25, 2010 @05:49PM (#32697724)

        And it may have been dismissed. Apple is very much about form over all else. The most important thing to them is how something looks. Features and function get subverted to that end. They've had other devices with problems due to their designs. Time Capsules are an example. They have a bad habit of failing after a year and a half or so, way more than you'd expect. Reason is the internal power adapter. It puts too much heat in the small case and causes failures. The smart thing would have been to have it external, but that would ruin the look.

        So Apple may have known this was a problem and said "Fuck it, people can just hold it as not to touch the antennas. We don't want to hurt the looks."

        • Re: (Score:3, Interesting)

          I feel like you're only half right.

          Apple's belief has always been that function FOLLOWS form. The user interface guidelines that they publish dictate form because it results in better function from a user perspective.

          This still holds true for the iPhone 4; getting Facetime to work is function, getting it to work without a bunch of tedious setup is form. Because they required it to work without a bunch of tedious setup, we're only now seeing it in generation 4 of the phone; before pure function is allowed ou

      • Re:Cue the fanbois (Score:5, Interesting)

        by Anonymous Coward on Friday June 25, 2010 @05:58PM (#32697820)

        So how come this problem was not identified during the system test of the device?

        Because - you'll really love this - they put it in an iphone 3 case when they were supposed to be testing it so as to keep the super shiny design secret. Really. The product they were testing wasn't the product they were planning to launch. Bunch. Of. Cowboys.

      • Re: (Score:3, Interesting)

        by Lars T. ( 470328 )

        Next thing you know, holding a cell phone with the thumb and forefinger by the top right corner will become the fashionable way for any of the cognoscenti to hold their phones.

        So how come this problem was not identified during the system test of the device? Were all the testers instructed to hold it that way? Or maybe they identified it, but did not have the courage to report it?

        Or maybe it doesn't happen on all iPhones. http://www.engadget.com/2010/06/24/some-iphone-4-models-see-signals-drop-to-0-when-held-left-handed/ [engadget.com]

        One iPhone 4 demonstrated the issue everytime it was held in our left hand (...) Our second UK-purchased iPhone 4 was fine, showing none of these handling symptoms. (...) P.P.S. Since some of you are asking, our review unit showed none of these issues.

    • by Anonymous Coward

      They all want to flood the Net with their obligatory iPhone 'reviews' and 'reactions' claiming:

      "It's amazing!"

      "A must upgrade for all existing iPhone owning Hipster Douchebags!"

      "Magical!"

      "Teh best thing evah!!!"

      while the actual piece of crap iPhone 4 is:

      Ugly
      Defectively designed
      Runs an outdated OS

      No wonder Google kicked Apple and the iPhone into 3rd place in sales and Android is now selling at roughly 50-60 million phones a year.

    • Re: (Score:3, Funny)

      by Anonymous Coward

      Next thing you know, holding a cell phone with the thumb and forefinger by the top right corner will become the fashionable

      The japanese demonstrating proper handphone technique:
      http://photos-451.friendster.com/e1/photos/15/48/18428451/1_246234319l.jpg

    • Re:Cue the fanbois (Score:5, Insightful)

      by Hope Thelps ( 322083 ) on Friday June 25, 2010 @05:47PM (#32697696)

      It Just Works. As long as you hold it the way Steve Jobs instructs you to. Coming from the supposed experts on user interface this is a major let down. Users holding the phone the way that comes most naturally to them are not wrong - the product is wrong.

  • Cases (Score:5, Interesting)

    by Peach Rings ( 1782482 ) on Friday June 25, 2010 @05:11PM (#32697304) Homepage

    How will wrapping the phone in a case and then holding it the same way as before fix the problem?

    • Re:Cases (Score:5, Informative)

      by dingen ( 958134 ) on Friday June 25, 2010 @05:15PM (#32697332)

      Because the case is made out of rubber and runs around the phone, effectively isolating you from the antennas, avoiding the antennas to connect to each other through you.

      • form over function (Score:5, Insightful)

        by nobodyman ( 90587 ) on Friday June 25, 2010 @05:31PM (#32697516) Homepage

        Of course, apple could have easily designed the phone with with a some plastic along the side, but this would go against their aesthetic "vision". Anyone who has used an Apple mouse (*any* Apple mouse) knows that ergonomics takes a back-seat to physical appearance. Always.

        • by wfolta ( 603698 ) on Friday June 25, 2010 @06:29PM (#32698180)

          Never used a Magic Mouse, I see. They're incredible.

      • Re:Cases (Score:5, Interesting)

        by icebike ( 68054 ) on Friday June 25, 2010 @06:02PM (#32697862)

        Exactly.

        Its not that the antenna is at the bottom, its because it is external, and metal, and skin is conductive.

        This is a fundamental design flaw that I can't believe they let slip. Now they will probably have to offer discounts on "bumpers" to bring the phone back up to published specifications.

        Using external antennas that can be shorted by normal hand moisture! I'm not aware of any other phone that does this. Why was it necessary with a glass backed case? The antenna could have been at the bottom like prior iphones. [maccompanion.com]

        There is SO Much about this iPhone release (hardware and software) that has been problematic that I am starting to believe Apple's claims that the leak of the "lost" phone was indeed damaging to Apple. I think it forced their hand, and cornered them into releasing a phone that was not yet ready with software that still had a lot of problems.
        The fanboys will be here momentarily to mod this down. Sigh.

        • Re:Cases (Score:5, Interesting)

          by Gary W. Longsine ( 124661 ) on Friday June 25, 2010 @07:37PM (#32698692) Homepage Journal
          I was initially skeptical that this might be software related, but recent rumors have a plausible software theory. The new iOS 4 has a new algorithm for picking the tower and channel that the phone uses, when it can see more than one. It appears that this mechanism may have a defect which is triggered by attenuating the signal (such as by bridging the two antennae with salty skin). This appears to cause the phone to decide to attempt switching channels. The speculation is that the timing is off, and the phone sometimes reports "no signal" rather than deciding to switch or stay put.

          Death Grip hysteria may end Monday with iOS 4.01 [appleinsider.com]

          The issue described is plausible, and fits some of the observations.
          • Some folk can reproduce this problem, basically at will (one of the magazine review sites).
          • Other folk are unable to reproduce this problem, at all (another reviewer at the NYT).
          • At least some folk who can reproduce this issue are doing so in areas where reception was previously known to be marginal (including one of my developers at his house).
          • The problem may have been harder to diagnose during Apple's testing, due to pre-release testing taking place inside insulated cases, thus the problem would be triggered less often, and not in associate with anything special that the user would notice (holding the phone in a certain way). The frequency of dropped calls might have been within the "normal" range for the AT&T network, given the small sample size of a few hundred test users. (Apple's off site testing includes hundreds of people, but that's actually a pretty small sample size, compared to the 600,000 people using the phone today.)

          It will be interesting to see if a software patch emerges within a few days or even weeks, and cures this issue. If it does, I'll think back to several cell phones I had previously, which had problems that I could and did reproduce, and reported clearly to the vendors (both network and cell maker) and for which no patches were forthcoming, ever, during the life of the phone. Regular software updates for iPhone are a damn sight better than the old way, where the answer to any problem was "buy the new version of the phone you just bought a month ago".

          • Re:Cases (Score:4, Interesting)

            by icebike ( 68054 ) on Friday June 25, 2010 @07:54PM (#32698814)

            For this theory to be believable, the phone would have to be failing one other key feature of cell tower hopping, namely keeping track of the relative signal strength of multiple towers at all times.

            Attenuation would affect all towers in the same band roughly evenly. It might not affect different bands the same, and the phone might be dropping to EDGE of something like that.

            But I still don't see how this gets out of the lab and thru field testing.

      • Re:Cases (Score:5, Funny)

        by yakumo.unr ( 833476 ) on Friday June 25, 2010 @06:18PM (#32698066) Homepage

        So, what they're saying is, all phones suffer from this, apart from any phone that has the aerial behind an insulating layer, such as a plastic case.

        Off topic, we're the only phone with the external metalwork acting as the aerial, isn't that awesome.

        Don't forget all phones suffer this defect, so it's not a design defect, no really.

    • Re:Cases (Score:4, Informative)

      by Loomismeister ( 1589505 ) on Friday June 25, 2010 @05:15PM (#32697346)

      The skin connects the front and back antennas through electrical conductivity. If there is a case blocking the connection the problem doesn't happen.

    • by Linegod ( 9952 )

      RTFAs. You are not in direct contact.

    • Re:Cases (Score:4, Informative)

      by antibryce ( 124264 ) on Friday June 25, 2010 @05:17PM (#32697368)

      the problem comes about when your hand shorts the two metal bits together. Put a case on them and you won't short them.

    • Re:Cases (Score:5, Insightful)

      by wramsdel ( 463149 ) on Friday June 25, 2010 @05:21PM (#32697420)

      It'll insulate the metallic ring that's "part of the antenna system", which might mean "the antenna" or might mean "some other element that helps the antenna do its work" (i.e. a resonant grounding piece). Antennas are tuned, resonant, structures...think of a tuning fork that needs to oscillate at a certain frequency. Bridging the gap between the two exposed elements changes the electrical characteristics of it such that the antenna becomes detuned and reception is impaired. By applying a case, your hand can no longer come in contact with the ring, so the antenna isn't as severely detuned and the cell phone signal isn't as attenuated. I say "as severely" because there will always be some impact when your hand is in reasonable proximity to the device, but it won't be of the magnitude that direct contact would be.

    • by nwf ( 25607 )

      And the real question is why they made the bottom strip out of metal since it's not an antenna. Just make it out of plastic and conduction will be less of a problem.Your hand will still affect it, but perhaps not as much.

      • Re: (Score:3, Insightful)

        by PPalmgren ( 1009823 )

        Form over function has been Apple's M.O. when it comes to certain design choices with their devices, something like this shouldn't be surprising. Its also the reason a lot of people buy their devices.

        Apple sells Shiny, and this is a result.

      • Re:Cases (Score:4, Interesting)

        by dangitman ( 862676 ) on Friday June 25, 2010 @06:06PM (#32697928)

        And the real question is why they made the bottom strip out of metal since it's not an antenna.

        Perhaps because it *is* an antenna? It doesn't have just one antenna, but multiple antennae circling the phone, for Wi-Fi, GSM and Bluetooth.

    • Re:Cases (Score:5, Interesting)

      by cybereal ( 621599 ) on Friday June 25, 2010 @08:43PM (#32699144) Homepage

      The effect of attentuation drops off exponentially as you remove the attenuating obstruction from the antenna. However, there is reason to believe that there is a different problem besides attenuation affecting a very small number of handsets. Personally I suspect some kind of ground fault in the casing leading to a magnetic field interfering with the radio itself. This wouldn't demonstrate itself as the loss of a couple bars, it would be complete or nearly complete loss of signal.

      That said, I have an iPhone 4 and cannot reproduce any of the reported problems at all no matter what I do. I have to put my phone in what almost amounts to a faraday cage (a steel lock box) just to see any signal degradation. But a friend of mine has seen the problem occur with nothing but the tip of his finger placed over the antenna on the left side, specifically when touching the metal. The metal plates are not the antenna, the black lines are, so what this tells me is that there is some issue with grounding of the body in that phone. But until I can have him try his "magic finger" on my own iPhone, I wouldn't jump to any real conclusions. None of the reports so far have been remotely scientific. There are numerous variables and without any cross checking it's all guesses for now. Attenuation will definitely occur but it's usually not so dramatic as to go from five bars to "Searching..." like this friend of mine is seeing.

  • I suspect they placed the antenna there to minimize the amount of RF energy exposure to the brain but now you'll have to be careful about how you hold it.
  • Re: (Score:2, Funny)

    Comment removed based on user account deletion
    • by Hurricane78 ( 562437 ) <deleted&slashdot,org> on Friday June 25, 2010 @05:53PM (#32697762)

      Geeks generally don’t buy Apple products. They buy a Linux phone from an obscure company that is also barely usable as a phone, but at least completely hackable.
      Hipsters and valley girls buy Apple products. Oh, and those people that drive Priuses. ^^

      • Oh, I guess that's funny in a Slashdot sorta way, but I'm not the first person to notice that conventions of programmers, like Java One, or BSDCon or various hacker and security geek conferences are seas of glowing Apple logos, the past few years. I know that among the programmers I know, it's actually the best programmers (the ones that I would recruit for any project on any platform with any language) who are nearly all on Mac OS X. Maintenance programmers tend to stick with the platform they work on du
  • Another person (Score:3, Insightful)

    by geekoid ( 135745 ) <{moc.oohay} {ta} {dnaltropnidad}> on Friday June 25, 2010 @05:15PM (#32697344) Homepage Journal

    who would rather be part of a group then have a properly working device.

    Sad really.

  • Simply ... (Score:5, Funny)

    by randyzoch ( 689187 ) on Friday June 25, 2010 @05:18PM (#32697374)
    1) Stand on one leg, preferably facing the cell tower. 2) Use your other leg to form a crude counterpoise for the iPhone4's various antennas. Also, experiments in dry/low-humidity regions which lead to dry/chapped hands may also contribute to your success making and holding a call. What other company could get away with producing a product like this and succeed?
  • All of a sudden Apple offers a case for the iPhone themselves, in the form a rubber band that runs around the phone, which not only protects the phone when dropped, but also isolates the user from the antennas. This case is exactly the cure you need for the antenna-problem.

    Could it be possible that the rubber band was actually a part of the original design of this phone, but later made optional in order to rake in more cash? If so, I really think Apple should hand out free cases to people experiencing these

    • Re: (Score:2, Informative)

      by Anonymous Coward

      You forgot to mention it's a $29 rubber band.

      • by dingen ( 958134 )

        That's exactly the point I'm trying to make: was the rubber band perhaps part of the original iPhone 4 design, but made an option so it could be sold for 30 dollars a pop?

        If so, that would be a pretty terrible way to rake in a few extra dollars, because the phone is effectively crippled in its current, naked, form.

  • by MightyMartian ( 840721 ) on Friday June 25, 2010 @05:19PM (#32697400) Journal

    "For best results, levitate one inch from your ears."

    • Re: (Score:3, Funny)

      You're just jealous that your reality distortion field is so weak it can't even levitate a cellphone a mere inch away from you! ~

  • The iPhone 4 has two symmetrical slots in the stainless frame. If you short these slots, or cover them with your hand, the antenna performance will suffer (see this video I found on YouTube). There is no way around this, it's a design compromise that is forced by the requirements of the FCC, AT&T, Apple's marketing department and Apple's industrial designers, to name a few.

    Possible solutions include:
    • having another small slot so the two antennae aren't right next to each other and you'd have to s
    • Possible solutions include:
      o having another small slot so the two antennae aren't right next to each other and you'd have to short both slots.
      o Cover with a non-conductive coating
      o Put the antennae actually inside the phone.

      Getting an android.

    • by SuperKendall ( 25149 ) on Friday June 25, 2010 @05:42PM (#32697654)

      They already had the phone inside the case in previous generations, the external antenna does improve the signal. No need to throw the baby out with the bathwater. A light non-conductive coating would work perfectly well.

  • QA (Score:2, Funny)

    Thats what you get for making you engineers hide the product in public by dressing it in an iphone 3 case during QA. Oops!
  • by phonewebcam ( 446772 ) on Friday June 25, 2010 @05:31PM (#32697514) Homepage

    Worse reception than the iPhone3 - check.
    Still tied to the worst US carrier - check.

    But hey, facetime is so awesome it overcomes all this...

    Realtime video calls which exceed the definition of the human retina? - cheC&&^& >>>>>CARRIER LOST

  • by Chad Birch ( 1222564 ) on Friday June 25, 2010 @05:39PM (#32697608)
    Saw a great post on reddit earlier today [reddit.com] where a user goes through a bunch of Apple's own advertising to see how they've shown the phone being held.
  • by Namarrgon ( 105036 ) on Friday June 25, 2010 @05:41PM (#32697632) Homepage
    This guy is an expert in antenna design from Aalborg University, and predicted this [google.dk] two weeks ago.
  • FCC? (Score:4, Insightful)

    by guspasho ( 941623 ) on Friday June 25, 2010 @05:47PM (#32697698)

    A blog post from an antenna design company explains that the reception problems are probably the direct result of phone design adapting to FCC requirements.

    Because it has nothing to do with their decision to place the antennae on the exterior of the device.

  • by DeadCatX2 ( 950953 ) on Friday June 25, 2010 @05:53PM (#32697770) Journal

    ...then why is it that this is the first time so many people are experiencing this problem?

    • by dingen ( 958134 ) on Friday June 25, 2010 @06:54PM (#32698422)
      Because it's bullshit. No other phone has a conductive casing with the antennas attached to it. Now we know why.
    • Re: (Score:3, Interesting)

      by alvinrod ( 889928 )
      Funny thing is that it's not the first time. Some reproduced the issue with an old Nokia candy-bar style phone [youtube.com] and put a video of it up on youtube. I don't have the link handy, but some site pointed out a Nexus One discussion thread from several months ago that discussed a the same issue. Just for fun I just took my own phone out of my pocket and observed the different in signal strength when it's just sitting on my desk and when I hold it. It loses a bar, but I've never noticed before because I've never th
  • by SuperKendall ( 25149 ) on Friday June 25, 2010 @06:34PM (#32698232)

    I think the reason they may not have found this in testing, is because it seems that you have to have slightly sweaty hands to trigger the problem. Just after running through an airport I was able to replicate the speed drop, but sitting on the plane a little later I could not see a network speed drop no matter how tightly I gripped the edges.

    The tested mostly in winter, now it's summer - leading more people to have this problem.

  • One Antenna? (Score:3, Insightful)

    by PPH ( 736903 ) on Friday June 25, 2010 @06:36PM (#32698260)

    I've been working with s device that has four antenna patches, a system to monitor the received signal strength from each, the transmitted SWR, and based upon these inputs, select the best antenna to use. Its not a cell phone, per se, but it operates on GSM systems and cannot be installed in a controlled environment (much like not being able to predict how a user will grab a phone).

  • Love Glove it (Score:3, Insightful)

    by BlackHawk-666 ( 560896 ) on Friday June 25, 2010 @09:53PM (#32699498)

    Slip a condom on that iPhone before you use it; honestly people - safe sex begins with safe phone calls to arrange the booty call.

Think of it! With VLSI we can pack 100 ENIACs in 1 sq. cm.!

Working...