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Apple To Issue a 'Fix' For iPhone 4 Reception Perception

Lisandro and several other readers let us know that Apple has just released a statement addressing the signal issues a lot of users are having with their iPhone 4. They claim to have discovered the cause for the drop in bars, which is "both simple and surprising" — a wrong formula used to calculate how many bars are displayed for a given signal strength. "Upon investigation, we were stunned to find that the formula we use to calculate how many bars of signal strength to display is totally wrong. ... we sometimes display 4 bars when we should be displaying as few as 2 bars. Users observing a drop of several bars when they grip their iPhone in a certain way are most likely in an area with very weak signal strength, but they don’t know it because we are erroneously displaying 4 or 5 bars. Their big drop in bars is because their high bars were never real in the first place. ... We will issue a free software update within a few weeks that incorporates the corrected formula. Since this mistake has been present since the original iPhone, this software update will also be available for the iPhone 3GS and iPhone 3G." Wired notes that there is still a signal drop when the iPhone 4 is gripped in particular ways.

34 of 534 comments (clear)

  1. Formula change by jolyonr · · Score: 4, Funny

    if(bar_count3) barcount=3;

    --


    Please read my Canon EOS tech blog at http://www.everyothershot.com
    1. Re:Formula change by jolyonr · · Score: 4, Funny

      stupid slashdot html ruined that! That'll teach me not to use preview. if (bar_count LESS_THAN 3)....

      --


      Please read my Canon EOS tech blog at http://www.everyothershot.com
    2. Re:Formula change by matt4077 · · Score: 4, Informative

      It's actually the other way around, but never mind.

      Anyway, I'm not sure what to make of this. On one hand, this will certainly earn a fair amount of ridicule as it sounds like redefining reality to what Apple wants it to be. A fix to the Reality Distortion Field, so to say.

      OTOH, I've had some experience with sensors, and there's sometimes ambiguity to how the signals should be evaluated/presented. I'd guess that a logarithmic scale is a better fit for the relationship of absolute signal strength and perceived quality than a linear one. If they previously used a linear scale, this update might be appropriate.

      This doesn't change the fact that the signal strength changes with how you hold the phone. If the change manifests itself only in fewer bars, everything will be alright. If actual call quality or reliability is affected, this change won't do anything for that

    3. Re:Formula change by NotBornYesterday · · Score: 4, Funny

      Well, I guess we now know how AT&T got the idea that they have "more bars in more places" ...

      --
      I prefer rogues to imbeciles because they sometimes take a rest.
    4. Re:Formula change by msauve · · Score: 5, Informative

      With digital phones, it's not necessarily signal strength (cell phone parlance = RSSI, Received Signal Strength Indication) you want to display. You want to include some measure of the signal/noise ratio, since that is a better indicator of a phone's ability to communicate.

      And, in fact, that's what most cell phones do. For CDMA, it's usually some combination of Ec/I0 with signal strength, and for GSM it's some combo of reciprocal bit error rate combined with signal strength. Often time averaged and perhaps peak reading. So it's not just a simple "x dB RSSI = y bars" calculation. The combined metric is called SQE (Signal Quality Estimation).

      --
      "National Security is the chief cause of national insecurity." - Celine's First Law
    5. Re:Formula change by BobMcD · · Score: 4, Insightful

      Again about that AC activity that always supports the vendor in question, in any discussion.

      Man up and log in. It isn't really all that hard.

    6. Re:Formula change by omnichad · · Score: 4, Funny

      Apparently it's more iphones in more bars, if the missing prototype is any indication.

    7. Re:Formula change by yabos · · Score: 4, Insightful

      The "fix" will simply allow someone to realize their signal sucks to begin with. If they are showing 1 bar and the call drops then they expect that, but if they're erroneously showing 4-5 bars and the signal drops they think there's a huge problem. I think this "error" is not an error at all, and Apple really set this bar scale like that on purpose for marketing purposes. People always think more bars is better so they calibrate it to show 5 bars even if the signal sucks.

    8. Re:Formula change by shawn(at)fsu · · Score: 4, Insightful

      How did this go unnoticed so long? I mean 5 bars on the AT&T network and no one thought that was suspicious?

      --
      500 dollar reward for tip(s) leading to the arrest of the person(s) who stole my sig.
    9. Re:Formula change by DJRumpy · · Score: 5, Informative

      Yes and no. The issue had to do with the scale used. From AppleInsider:

      "Apple's iOS allots nearly 40 percent of reception levels to five bars, from -51 dB to -91 dB. But the distance from four bars to one bar of reception is much less, from -91 dB to -113 dB."

      Unless you live under a rock, or have never cracked open ANY cell phone manual, you would know that they all recommend avoiding the lower left side where the antenna is located. The problem with Apple's configuration is that they used 5 bars for -51 to -91 db, which in itself is fine, since any call with those signal strengths would be very stable.

      The problem has to do with dropping signal strength when you cover the antenna. Although you couldn't cause any phone to lose 63 db from grabbing it, getting a 20 db drop in signal strength isn't all that uncommon. If someone was in the weaker 5 bar range (say -90 db), which is still a decent signal, the phone would display 5 bars. When you covered the antenna, you could potentially get a 20 db drop, bringing you down to -110 db, which is a very poor signal. It gave the impression that someone went from 5 bars to no bars, or even no service (no service being very possible with -110 db).

      There are no standards defining what dB is represented by the number of bars. It is totally up to the hardware manufacturer. As to whether or not this was a mistake, who can say? The haters will claim it's a marketing ploy, the lovers will claim it's a fair way to rate the signal. I'll probably fall in between.

      What this fix will do is better represent the number of bars by signal strength in a more linear fashion, so that -90 might only be three or two bars, and covering the antenna would drop you to 1 or no bars. Although any phone might make a call at 1 bar, you should also expect that you might drop it with such a poor signal.

      Frankly, I think most of the posts in these and other forums are full of 'noise' from people who hate Apple, from Droid fans, to people who just dislike them for their closed systems. It's an ideal way for them to take shots by spreading FUD and making the issue appear far worse than it actually is. Unfortunately, it also makes it much more difficult for people to judge the scope of the problem, which in itself is a win for Droid from a marketing perspective. I do know that I haven't dropped a single call on the iP4 regardless of the bar display. I suspect most fall into the same category. Reviews of the phone also back up the same. Dropped calls have actually been reduced under the iP4, regardless of the number of bars displayed. Anandtech actually has a nice write up and some more thorough testing of signal strength. What they found is that the exposed antenna's do make the iPhone 4 more susceptible to interference, but not so much that it would affect people with decent signal strength. It actually performs better than a droid for signal loss when it's in a cover:

      http://www.anandtech.com/show/3794/the-iphone-4-review/2

      The Antenna is Improved
      From my day of testing, I've determined that the iPhone 4 performs much better than the 3GS in situations where signal is very low, at -113 dBm (1 bar). Previously, dropping this low all but guaranteed that calls would drop, fail to be placed, and data would no longer be transacted at all. I can honestly say that I've never held onto so many calls and data simultaneously on 1 bar at -113 dBm as I have with the iPhone 4, so it's readily apparent that the new baseband hardware is much more sensitive compared to what was in the 3GS. The difference is that reception is massively better on the iPhone 4 in actual use.

      With my bumper case on, I made it further into dead zones than ever before, and into marginal areas that would always drop calls without any problems at all. It's amazing really to experience the difference in sensitivity the iPhone 4 brings compared to the 3GS, and issues from holding the phone aside, reception is

  2. These aren't the bars you're looking for... by ender1598 · · Score: 5, Funny

    Just force hold it next to your ear like the rest of us!

    --
    There are 10 kinds of people in the world; those that understand binary and those that do not.
  3. Applies to all iPhones by Sockatume · · Score: 4, Informative

    This isn't a fix for the attenuation caused by touching part of the antenna, it's a fix for a longstanding software issue that makes it harder to manage. The issue's still there, and if you're seeing lower signal or slower speeds on your iPhone 4 than your previous iPhone, the patch won't fix that.

    --
    No kidding!!! What do you say at this point?
    1. Re:Applies to all iPhones by Texodore · · Score: 4, Informative

      This needs to get out. anandtech did a bang up job investigating how strong the signal is based on the bars you have and found it to be logarithmic and heavily weighted to having 5 bars. This is probably a software fix to make it more linear. It's not fixing the antenna issue or all the dropped calls you'll still get because of the grip of death.

  4. Breaking news by maxume · · Score: 4, Funny

    Goatse man works at Apple.

    I mean, they had to pull that out of somewhere.

    --
    Nerd rage is the funniest rage.
  5. bars by mark72005 · · Score: 5, Funny

    Well, AT&T does say "More bars in more places"

  6. Programming is so easy by DoofusOfDeath · · Score: 5, Funny

    that Marketing fixed the bug!

    short compute_bars(double signal_strengh_dB) {
      # Original approach. Not sufficiently diplomatic. -John from PR
      # return min(0, max(5, log(signal_strengh_dB));
     
      # Better approach. - John from PR.
      # Commenting this out. You're an idiot. Display only has 5 bars. -Dave from R&D.
      #return 11;
     
      # This makes me feel dirty. -Dave from R&D.
      # Wrong code. See correct fix at bottom of function. -Steve
      # return min(3, max(5, log(signal_strengh_dB));
     
      # Simple, elegant. You guys suck at programming. -Steve
      return reality_distortion_field( signal_strengh_dB );
    }

    1. Re:Programming is so easy by Rockoon · · Score: 4, Insightful

      I have inside information. This is the actual code after the fix:

      if (user.fanboy) marketing.damagecontrol.emit("you are holding it wrong");
      else if (user.dumberthanthat) marketing.damagecontrol.emit("there was never a reception problem. we just displayed the wrong number of bars");
      else if (user.inclassactionlawsuit) marketing.damagecontrol.emit("here is a coupon for $20 off our $30 rubber bumper, which cost us pennies to make");

      --
      "His name was James Damore."
  7. Anand Tech by ChipMonk · · Score: 5, Informative

    There's a serious analysis here, with some extra commentary by OS News here.

  8. Re:I wonder... by ZeroExistenZ · · Score: 5, Funny

    Does anyone get the impression they started looking for any excuse for their crap design and this was the best they could come up with?

    "We need to do something QUICK! The media is raging on this issue! Even the general media!!! Even ads are mocking us!"
    "We can design an isolation band to put on the phone, and market it as the next fashionable thing"
    "people would rage it's not free and would cost too much to ship out to everyone.. any other idea's?"
    "Recall! Redesign! WE HAVE NO CHOICE"
    "TOO EXPENSIVE! and we just fired our antenna guys."
    programmer: "I can write a tool to detect if they're lefties by usage stats..."
    "... listening."
    "And then adjust their reception display."
    "What do you need?!"
    "5 hookers, one masseuse, 2 days of coding and unlimited supply of skittles."
    "GIVE THIS MAN WHAT HE NEEDS! Get to work! Good job."

    --
    I think we can keep recursing like this until someone returns 1
  9. Nice way to pass the burden by ProppaT · · Score: 4, Insightful

    It's well known that the iPhone has never reported reception as it should. So what, they fix this software bug and it becomes apparent to everyone that their AT&T reception sucks. So, is Apple trying to place the blame on AT&Ts shoddy service instead of taking the blame for designing a defective antenna? This is ludicrous.

    It's sad, if it was any other manufacturer, people would return these defective phones in droves and there would be a massive recall. Because it's an iPhone people are willing to ignore these issues that should honestly result in a class action lawsuit to extend the return period from 30 days to 60 or 90 days with a free optional rubber bumper. This whole situation is absurd.

    --
    Wise men say, "Forgiveness is divine, but never pay full price for late pizza."
  10. It is just PR "managing" the bad press ... by janoc · · Score: 4, Interesting
    Software patch cannot fix signal attenuation from a hand. Why does this look like only an attempt to make the complaints and bad press go away by making the problem harder to notice? If you have no bars displayed, you wouldn't notice that you are losing signal from holding the phone, because you would be under the impression that the coverage is poor. And in an area with a strong signal you do not see the issue anyway, because the signal level is strong enough to saturate the meter even if your hand is over the antenna.

    It looks more like a clever way to disguise the problem and push the blame on the carrier by hiding behind poor coverage, nothing more.

    It reminds me of Sony (I think it was them) who "fixed" one of their overheating laptop series by having users download a "patch" that would turn off the power management in Windows and make the fans go non-stop. It certainly stopped the overheating, but at the price of shortened fan life and a very noisy machine ...

  11. Re:Joke by Chrisq · · Score: 5, Funny

    An iPhone walks into a bar... oh wait it was a guy walks into a bar and leaves his iPhone

    He probably had a similar problem to the iPhone when he left .... seeing two bars when there should only be one.

  12. Re:Not so perfect iPhone? by JohnBailey · · Score: 4, Funny

    So, instead of solving the problem, they just downgraded the problem??? Sorry iPhone fans, but it looks like your phone cannot event manage something so simple and base as signal strength!!!!!!

    Nonsense.. Apple has fixed the problem of the bars going down by recalculating the scale. This is perfectly acceptable. It's an elegant cost efficient and perfectly practical solution. I mean.. If a warning light is blinking, just take the bulb out. No more warning light, problem solved.. yes?

    --
    It is difficult to get a man to understand something when his job depends on not understanding it.
  13. Re:Do The Right Thing - A Steve Jobs Joint by not+already+in+use · · Score: 4, Insightful

    And if I see one single comment pimping the Android in this story, I'll have all you Android fans know that you have become what you hate.

    No, I haven't become what I hate. You don't see me supporting an abusive, shitty company so I can have a trendy, overpriced device. I don't slap Google stickers on my car and blindly claim my device is superior to all others.

    Why can't someone use a product they like for any reason at all? Is that not allowed anymore, or do we all have to care about the same things you care about and use the same phone that you use?

    I love the fact that you are being preemptively defensive. If anything, its indicative of the fact that many iPhone users are emotionally attached to their overrated device and have an allegiance to a terrible company.

    --
    Similes are like metaphors
  14. More accurate version.. by Dynamoo · · Score: 4, Funny

    Or a more accurate version.. “Upon investigation we discovered that we’d f—ked up the antenna design and were desperate to find a way out. So, ignoring the fact that the iPhone 4 actually drops calls and that covering the antenna with insulation such as a rubber bumper, tape or even nail varnish fixes the problem, we’ve come up with some guff about the displayed signal strength being wrong. So from now on, your iPhone 4 will only display 2 bars for signal strength no matter where you are, and if you have a problem with that I suggest you talk to your carrier. Hey, at least we didn’t have to shitcan our entire product line after only 42 days like Microsoft did with the KIN.. well, not yet”.

    --
    Never email donotemail@WeAreSpammers.com
  15. Re:Actual formula change by eln · · Score: 5, Insightful

    They are not solving the problem as reported, they are redefining the problem to something they can fix without a hardware recall.

    The problem as reported is that the signal strength weakens consistently when the phone is held in a certain way. This is clearly a hardware issue, but hardware issues are expensive to fix. So, Apple fixes a similar but ultimately unrelated problem via a much cheaper software patch and hopes their loyal fan base will just pay attention to the fact that *a* problem has been fixed, even if it isn't *the* problem everyone is complaining about.

    Unless Apple honestly believes this software patch will fix the actual reported problem, which I find very difficult to believe, they are acting in an unethical and customer-unfriendly manner in order to avoid the real solution, which would be to issue a recall of their flagship product and fix the hardware.

  16. Re:Actual formula change by Anonymous Coward · · Score: 4, Informative

    Apple use a Qualcomm chipset for their UMTS (3G) radio access. That chipset controls which sectors (base-stations) the handset is talking to. In UMTS (3G) the handset can be sending/receiving data to/from multiple sectors anyway (called soft-handoff). Thats why both Apple and HTC or RIM handsets tend to be a lot slower to re-select between cells than your average Nokia - who use their own chipset. Handling the radio connections is all done by the Quallcomm chipset part.

    The issue here is in how Apple's OS - running on the ARM processor which is not responsible for the radio link interprets the numbers that are passed to it about signal strength and quality into a set of bars on the screen.

    Typically 3G phones use a simlpe measure of RSCP or RSSI (two signal strength indicators in UMTS signalling). What Apple seems to be saying is that the way in which they determined what number of bars to display for a given RSSI value was wrong. This is really well explained in this article - http://www.anandtech.com/show/3794/the-iphone-4-review/2.

    There are other paramters that are important though to how your phone actually operates. It is perfectly possible to have a very high signal strength in a particular location but very low quality/throughput. This can be caused by things such as Pilot Pollution - where multiple base-stations are interfering with each other. In UMTS (3G) this normally occurs if there are more than 3 base stations above a threshold signal strength. This can cause other parameters such as EcIo (Basically Signal to Noise Ratio) to be low despite the signal strength being high.
     

  17. Anandtech may have an explanation... by JorDan+Clock · · Score: 5, Informative

    Anandtech posted a review of the iPhone 4 the other day and they have a break down of the signal strength in dBm compared to how many bars are displayed. The specific page is here.

    Basically it looks like there is a huge range for what is considered five bars, and a small range for the remaining four bars.

  18. RSimple solution - return it. by tomhudson · · Score: 5, Informative

    It's Defective by Design (TM)

    For once, Apple copied Microsoft.

    Check the consumer protection legislation in your area. It probably has something along the lines of products needing to be fit for the purpose for which they were purchased for a reasonable length of time, taking into account the price paid.

    There are two types of warranties: Legal and Conventional.

    Conventional Warranty (limit your rights): We warrant foo for 1 year (no warranty on batteries, screens, keyboards, accessories, etc).

    Legal Warranty: Fitness for purpose for which it was purchased, taking into account price paid, etc. In other words, you paid $3k for that big-screen tv and it croaked 1 day after your conventional 1-year warranty expired? You can still use the legal warranty via small claims court. They can't hide behind the limitations of the conventional warranty - the conventional warranty is in addition to the legal warranty (which makes extended warranties stupid purchases).

    1. Re:RSimple solution - return it. by BasilBrush · · Score: 4, Informative

      Check the consumer protection legislation in your area. It probably has something along the lines of products needing to be fit for the purpose for which they were purchased for a reasonable length of time, taking into account the price paid.

      You don't need to do anything more than read the statement. It reminds customers that they can return their purchase if they are not satisfied within 30 days of purchase for a full refund. All iPhone 4s were purchased a lot less than 30 days ago.

  19. Dropped calls thing is a myth by SuperKendall · · Score: 4, Informative

    If you are going to bring up the anandtech study, you may also want to mention that the article states when signal quality is low the iPhone 4 is much better at keeping calls alive:

    From my day of testing, I've determined that the iPhone 4 performs much better than the 3GS in situations where signal is very low, at -113 dBm (1 bar). Previously, dropping this low all but guaranteed that calls would drop, fail to be placed, and data would no longer be transacted at all. I can honestly say that I've never held onto so many calls and data simultaneously on 1 bar at -113 dBm as I have with the iPhone 4...In reality, reporting based on SNR makes a lot more sense, since I couldn't make calls drop driving around an entire day cupping the phone, despite being at -113 dBm (1 bar) most of the time.

    I've not had dropped call issues from the iPhone4. That's not to say you will never have a dropped call, this is after all AT&T we're talking about here. But I have had much better results in making and keeping calls compared to the older phone, so people who are holding off buying an iPhone worried about dropped calls are doing themselves a disservice.

    For me, tightly gripping has more of an impact on data speed than calls - and even then, it doesn't always affect data speed. But it's again a worthwhile upgrade, because the phone has better latency and so network use feels more responsive as per DaringFireball.

    --
    "There is more worth loving than we have strength to love." - Brian Jay Stanley
  20. Re:Actual formula change by BasilBrush · · Score: 4, Insightful

    The problem as reported is that the signal strength weakens consistently when the phone is held in a certain way. This is clearly a hardware issue

    All mobile phones will have signal strength weakened when you cover the antenna area with the hand. That's physics, not a design problem. Whether you notice the problem or not depends on how strong the signal from the base station is in the first place.

    The problem reported was the number of bars that this lost. e.g. from the article that was linked to from the first slashdot article on this issue:

    "Signal drops from 4-5 bars to 'searching for signal...' when I hold it in my palm or cover up the line on the lower left side of the phone," reported a user identified as "yoshjosh" on the thread. "I understand that cell signals may degrade when you cover up the antenna, but I have never seen anything this severe, and I'm not holding the phone differently than I think most people hold their phones. This is a real issue."

    Other phones might drop one bar when you cover the antenna with your hand. The iPhone with it's current software might drop 4 bars. That doesn't mean that the signal to the iPhone is dropping more than the other phone. Just that the algorithm used for the display is different.

    If Apple is switching to the algorithm that the US carrier suggests, then that is a perfectly reasonable move.

    Want to see the same issue with other phones?

    Nokia E71.
    http://www.youtube.com/watch?v=gi1gHDa7-X0

    HTC Droid.
    http://www.youtube.com/watch?v=eaDE941PzQk

    Blackberry.
    http://www.youtube.com/watch?v=eaDE941PzQk

  21. Your assumption is incorrect by SuperKendall · · Score: 4, Informative

    BESIDES it doesn't matter - a dropped call is a dropped call. If the iPhone 4 drops calls in areas where other phones (like the iPhone 3) worked perfectly, then the problem...

    The iPhone4 does not drop calls in areas where other phones work perfectly. Instead of relying on your vast Apple Hater Rage to inform your opinion, why not try reading a carefully done study instead:

    From my day of testing, I've determined that the iPhone 4 performs much better than the 3GS in situations where signal is very low, at -113 dBm (1 bar). Previously, dropping this low all but guaranteed that calls would drop, fail to be placed, and data would no longer be transacted at all. I can honestly say that I've never held onto so many calls and data simultaneously on 1 bar at -113 dBm as I have with the iPhone 4...In reality, reporting based on SNR makes a lot more sense, since I couldn't make calls drop driving around an entire day cupping the phone, despite being at -113 dBm (1 bar) most of the time.

    The reality is that the iPhone 4 is BETTER at making and receiving calls. This is my own experience, and of the other people I know who have the phone - and also borne out by actual testing.

    As Apple said, if people think there is a problem they can just return the phones, no questions asked. But I don't think Apple will see many takers.

    --
    "There is more worth loving than we have strength to love." - Brian Jay Stanley
  22. Unhappy campers - Please take Apple's advice. by calstraycat · · Score: 5, Insightful

    To all the folks unhappy with both the performance of the new iPhone and Apple's response, please heed the advise in this portion of the press release:

    "As a reminder, if you are not fully satisfied, you can return your undamaged iPhone to any Apple Retail Store or the online Apple Store within 30 days of purchase for a full refund."

    Seriously. Please.

    All this ridiculous, over-the-top, self-righteous indignation and emotional hand-wringing over a gadget not meeting your expectations is just pathetic.

    Apple has taken a stand on this issue. They say it works as designed and claim the reception is better than their previous model. You think they're full of shit? Great. Quit posting whiney, indignant messages on the internet and return the goddam thing.

    If the problem is half as bad as all the stories make it out to be, Apple will be flooded with returns and that will have a much greater effect that millions of lines of internet bitching.

    Disclosure: I'm a satisfied owner of several Apple products. I don't own an iPhone and have no plans to purchase one. My wife and I have free-with-subscription LG phones on Verizon. Oh, and guess what? If I hold the phone by the bottom, signal degrades. If I hold it that way in an area with poor cell coverage, service is lost entirely. You think if I submit my sob story to Slashdot, Gizmodo, CNET, CNN, etc. they will make it front page news?