Anand Lal Shimpi reports for AnandTech, “When I set out to characterize and understand the iPhone 4’s antenna issue, I noticed that reports online varied wildly. Some claimed that they were always able to recreate a reception issue created by cupping the phone, yet others reported no change at all squeezing the phone tightly.”
“So, an entire day and more than a quarter tank of gas later, here are the results,” Lal Shimpi reports. “Holding the iPhone 4 without a case, in your left hand, crossing the black strip can result in a worst case drop of 24 dB in signal. As we’ll show in a second, how you hold the phone makes a huge difference across every smartphone – and we’ve tested thoroughly in 5 different positions.”
“Now, there are two vastly different possibilities for what happens to the bar visualization after you drop 24 dB. I happen to live less than one block from an AT&T UMTS tower (it’s across the street, literally), and have exceptionally strong signal in all of my house – it’s part of why I chose to live here, actually,” Lal Shimpi reports. “Signal is above -65 dBm in every single room, in most cases it’s at -51 dBm. When I incur that worst case drop of 24 dB from squeezing the phone, I fall down to -83 dBm, which is still visualized as 5 bars.”
Lal Shimpi reports, “However, in locales that have less signal, but where iOS still displays 5 bars, the drop of 24 dB is visualized much differently. For example, at another test location, signal without holding the phone is -89 dBm, which is still displayed as 5 bars. Cup the phone, and you’ll fall all the way to -113 dBm. All the bars dramatically disappear one after the other, people think they’ve dramatically lost all the signal, and you know the rest.”
“If you’re at 4 bars already, (which puts you on the low end of possible signal strengths), cupping the phone even more delicately is enough to push you the remaining 10 or so dB to cutoff. It doesn’t take much when you’re at 4 bars, which is why the visualization is flawed. Complicating matters is that signal is completely fine until down around 2 bars at -107 dBm,” Lal Shimpi reports. “If you add a bumper case to the iPhone 4, the signal strength drop from holding the device is on par if not better than other phones. In the exact same location, in the exact same orientation, I carefully measured my iPhone 3GS and Nexus One with the same AT&T microSIM in my newly made SIM adapter. After lots of testing, I decided on 5 different positions for holding the phone, and tested signal repeatedly. “
“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),” Lal Shimpi reports. “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.”
Lal Shimpi reports, “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 absolutely definitely improved. I felt like I was going places no iPhone had ever gone before. There’s no doubt in my mind this iPhone gets the best cellular reception yet, even though measured signal is lower than the 3GS.”
Lal Shimpi concludes, “The main downside to the iPhone 4 is the obvious lapse in Apple’s engineering judgment. The fact that Apple didn’t have the foresight to coat the stainless steel antenna band with even a fraction of an ounce worth of non-conductive material either tells us that Apple doesn’t care or that it simply doesn’t test thoroughly enough. The latter is a message we’ve seen a few times before with OS X issues, the iPhone 4 simply reinforces it. At the bare minimum Apple should give away its bumper case with every iPhone 4 sold. The best scenario is for Apple to coat the antenna and replace all existing phones with a revised model.The ideal situation is very costly for Apple but it is the right thing to do. Plus it’s not like Apple doesn’t have the resources to take care of its customers.”
Read much more in the full, very comprehensive (and not just about antennas) review – highly recommended as usual – here.
It’s a very good article but replacing all phones??? Because of this? When there is nothing really wrong with the phone? That’s just a retarded statement. Replacing 2 million phones because of this?
The best solution is to give every one that bought the iPhone 4 a rubber band so they can STFU
“That should be enough evidence for a judge to throw that new reception lawsuit out.”
Or the first run of iPhone4 owners should all be mailed bumpers at cost…. total cost..3 million dollars?
Future iPhone4s have the antenna coated, total cost 5 cents per phone?
Who cares about the number of bars!?!?!?
I don’t hear anyone saying that it drops calls more frequently than previous iPhones or other cell phones. That is the real metric that matters!
R2 wrote:
“”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.”
Yeah, exactly, WITH the bumper case on.
“The main downside to the iPhone 4 is the obvious lapse in Apple’s engineering judgment.”
The iPhone 4 had a chance to be world renowned for its excellent reception if Apple hadn’t fscked up. It would’ve been smooth sailing from here to iPhone 5 but instead we’ve got a big detour until Apple fixes this crap.”
What of this?
http://www.antennasys.com/antennasys-blog/2010/6/24/apple-iphone-4-antennas.html
By the way, I was in the Bentall Centre (London) Apple store yesterday and tried holding every display iPhone 4 they had, on 3 different carriers. Not one of them dropped a single bar, even with two hands covering all the black gaps in the steel band.
This sounds like it’s primarily a US problem frankly.
Protect your iPhone4 from the trolls’ AIDS-like symptoms of vitriol and alarmist rumors with a condom.
I disagree with the take. According to the much-recommended Anandtech review, the attenuation in the iPhone 4 from normal holding is ten times that of the 3GS and twice that of the Nexus One. The magnitude of it is large enough to cause a noticeable effect on a large (not majority) number of users.
To say that attenuation is to be expected from a cell phone is technically correct, but misleading because the effect is very pronounced in this phone compared to others. It’s like Toyota excusing their debacle by saying that recalls are an unavoidable part of the automobile industry. Would any of you accept that as an excuse?
Apple needs to provide more than a simple visual “fix” or their reputation for high quality products will be tarnished. A simple coating of the antennae would do, but I suspect it’s not going to happen (I hope I’m wrong) because it would imply that Apple is admitting that the current iPhone 4 is not a perfect piece of hardware.
To anyone who thinks the numbers shown in the Anandtech review are not significant, I’d like to hear why.