Apple Says iPhone 4 Reception Mystery Is Solved! AT&T's Signal Was Never Really There!

iphone4 antenna

Never mind all of those quick fixes and videos about iPhone 4 reception dropping out when you hold the new phone a certain way. Never mind the fake Steve Jobs letters telling a customer to relax (or not).

In a newly released letter to customers, Apple — the real Apple — says it's figured out why some iPhone 4 users are experiencing lower bars in their reception when the phone is held a certain way:

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. Our formula, in many instances, mistakenly displays 2 more bars than it should for a given signal strength. For example, 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.

This is what many had thought to be the case, and it makes sense since despite the media clamor about iPhone 4 failings based on videos of the "death grip" effect, many other users couldn't replicate the problem at all. And other users reported that the iPhone 4 actually delivered better reception than previous editions of the phone. Apple itself notes this:

At the same time, we continue to read articles and receive hundreds of emails from users saying that iPhone 4 reception is better than the iPhone 3GS. They are delighted. This matches our own experience and testing. What can explain all of this?

So what's happening is this: The iPhone 4's radio frequency and digital signal processing electronics seem to be better than ever at snagging and holding onto a cell phone mast's transmissions when you're at the edge of a signal zone. This is good news, folks.

But when you cover the antenna with your hand, the usually small signal attenuation you cause (which is the case for every phone, as Jobs pointed out previously) is enough to cause the signal strength to drop below what the iPhone 4's amplification and error-correction systems can cope with, causing it to close the transmission and you to lose the call. Since the iOS4 programming is incorrectly over-exaggerating the signal strength on the screen, you then peep at your phone and see four bars dropping down to one or none, and the more passionate owner will shout "Bad Apple!"

When Apple's upcoming free patch is applied to correct its signal meter algorithm, nothing about the phone's radio performance or electronics will change ... it's just that you'll see a weak signal displayed on screen (as you will on any phone at the edge of a signal zone) and won't be surprised when a call drops. Some will still cry foul at this, saying Apple's merely "covering up" the problem. It really isn't. A modern smartphone is genuinely a complex mix of radio frequency circuitry, sophisticated digital hardware, and software—it's a system of systems. Errors like this are almost inevitable, and sometimes defeat a "common sense" (and sometimes incorrect) interpretation.

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  • edouardbrauer

    Maybe the signal was there, but the bandwith was used by some strange applications.... Any idea of how lawfull intercept can work on a Iphone / Ipad ?

  • Bill Bucolo

    My Sprint line was always clear and consistent using a regular cell phone, but AT&T's signal does come and go. With my original iPhone, one minute I could have 5 bars, get and receive calls, a minute later I'd get one bar or "No Service." It would happen indoors or outside. With the 3GS I drop far less calls but it still isn't perfect. In any case I'd still rather have the iPhone because of all the other things it does.

  • John Benham

    I agree with Bruce O, if you sell something as an innovative improvement you'd better make it right.

    Also, its not reassuring that they couldn't get the signal strength algorithm right, its normally just displayed as a logarithmic function of the pre-detection signal strength. Hardly takes rocket science to get that right, and something that certainly should have been picked up in design verification testing. Sounds like a lot of corners were cut.

  • Louann Oravec

    At & T suck, thats why we switched out local phone to a different company. You could not pay me to switch from Verizon to any other cell company. We have had nothing but outstanding service with Verizon. We have had service with Verizon since before they were Verizon.

  • Bruce O

    Fact is when you own any of the previous iphones, which I believe most
    of the new IP4 purchasers are previous owners, and Steve promotes the
    new antenna design as being innovative and implies that call quality
    issues will be solved by the new antenna and AT&T's improvements by
    end of June. Then we are into July and these users find in the same
    places they were able to hold their previous iphones normally now they
    constantly drop calls and lock up data transmission only to find out
    that nothing is improved, they have a fatally flawed antenna design
    and the only thing apple is admitting to is lying about the reported
    signal strength.... Gives a new light to the AT&T campaign, "more bars
    in more places"

    I really think even we, Apple fanboys, wont be able to get over
    this..... Imagine the marketing jabs... Verizons commercials against
    ATT were very clever and damaging.... Apple's brilliant marketing with
    Justin Long ridiculing Microsoft.... Now I guess retribution will be a
    bitch. Apple stock is already taking a major slide since IP4.

    I'm sure Steve has already crucified the previous antenna engineers
    for making him look like an asshat. It's also ironic to see the current cover of fast company.

  • Tyler Gray

    Re: the cover comment. You might want to check up on the definition of "irony." Apple sold 1.7 million iPhone 4s in three days and in the face of the whole antenna dust-up. It's their most successful product launch ever. Love them or hate them, not even a potential flaw in the basic design of their marquee product can stop this company. Besides, there have to be wounds (self-inflicted here, likely) for company to prove itself invincible, don't there? Follow the logic. Even if iPhone 4 sales slow now, the cover line of the current issue of Fast Company has never been more accurate.