Tech —

Apple says iPhone 4 algorithm is to blame, not antenna

Apple has issued a statement about the iPhone 4 signal dropping issue, saying …



Simultaneously, Apple says it has gotten hundreds of e-mails saying that the iPhone 4 reception is better than the 3GS—this proved to be true in many cases for us during our testing of the iPhone 4, even though we could reliably reproduce the signal dropping problem.

Apple's explanation is that the iPhone—including 3G and 3GS—has always displayed too many bars given a certain level of signal strength. The company plans to adopt AT&T's recommended formula instead as part of its software update and has gone back to re-test everything.


The bar issue can be a complicated one—we wrote a feature on the disconnect between bars and cell signal back in 2008 that still applies today—but it's important to note that there is no industry standard for how signal translates into the bar display. Manufacturers generally make up their own scale and assign signal values to each bar, taking into consideration noise or interference that may be occurring in your environment.

Apple's explanation that it always used too many bars—especially for users in low signal areas—sounds like the company wasn't doing enough to account for interference or the other variables that come with overall signal strength, resident Ars programmer and former GSM/RF Engineer Clint Ecker told us. At the same time, the explanation gives us some pause—why has this problem in bar calculation only come up now and not previously if it has been in practice for two years already? Furthermore, Apple's statement doesn't address the very real issue of handsets losing up to 24dB of signal strength from simple bridging two of the phone's antennas—which is either a serious hardware flaw or another error in how the phone detunes its antennas.

Apple didn't give enough information to really know what's going on, but we cautiously await this software update that will claim to fix everything.

Update: Readers have reminded us that Apple actually bumped up its bar display as part of the release of iPhone OS 2.1, casting further doubt on Apple's apparent stunned-ness at the situation. "Improved accuracy of the 3G signal strength display" was one of the main listed features when 2.1 came out in September of 2008.

You must to comment.

Channel Ars Technica