Power-control software blamed for iPhone 3G reception issues

The iPhone 3G's reception problems have been blamed on flaky power-control software.

(Credit: CNET)

A plausible scenario for the iPhone 3G reception problems has emerged: it's a power thing.

RoughlyDrafted reported Thursday that a source with AT&T blamed "faulty" power-control software inside the iPhone 3G for the dropped calls and poor reception that owners have been experiencing since the device was released in July. In short, the iPhone 3G demands too much power--more than is necessary--from a local cell tower to maintain a connection, and when multiple iPhones try to glom onto the same tower, the problem snowballs.

The iPhone OS 2.0.2 software update was designed to fix this power-control problem, according to RoughlyDrafted's source. However, the source believes that the problems will not go away entirely until all iPhone 3G owners--or quite a few--upgrade to the 2.0.2 software:

In a mixed environment where users are running 2.0, 2.0.1, and 2.0.2, the power control problems of 2.0 and 2.0.1 will affect the 2.0.2 users. It is not the network that is fault but the interaction of the bad power control algorithm in 2.0 and 2.0.1 software and the network that is at fault. The sooner everybody is running 2.0.2 software the better things will be.

This explanation makes a lot of sense viewed against the stories of CNET readers over the past month of iPhone 3G flakiness. It would explain why the problems were more pervasive in populated areas with lots of iPhone 3G early adopters, such as San Francisco, Chicago, and New York. It would explain why those who updated to the 2.0.2 software didn't see improvements across the board. And it would explain why the problems are being reported around the world, not just on AT&T's network.

So, this saga may soon be coming to an end. If you haven't already updated to the 2.0.2 software, do so today, for the sake of your fellow iPhone 3G owners. Hopefully that process, combined with an iPhone 2.1 software update to get rid of the other bugs in the release, will allow people to use their iPhone 3Gs as designed.

The unanswered question--assuming this account is accurate--is why the iPhone 3G shipped with balky power-control software, something that ostensibly could have been discovered in testing?

[sanenazok]

Get ready for ... 3-2-1 DENIAL by Apple. Their products are perfect, after all.

[ballmerisanape]

They released an update to fix it... that's hardly a denial.

[eyepoker]

The problem was porbably known and apple shipped it anyway. they ship with issues all the time in other products, like their firewall not performing like a firewall at all - which would be obvious yet early systems were shipped with non-functional firewalls anyway. Its extremely important to Apple to maintain the high perceptions they've created as it is vital to their brand. then, sit back and look at Apple's response to the 3G connectivity issue - which was to ignore it. Again, admitting to a problem is contrary to the Apple Brand where "things just work". I'm not suprised at all.

[Zimm2]

Nor am I by surprised by you making accusations with no facts to back them...

[ballmerisanape]

How is fixing the problem ignoring it?

[technewsjunkie]

Apple is coming to get you!
Run away, run away!


"important to Apple maintain high perceptions". Get this dude, their products really work great! Get over it.

You're clueless. Apple products DO "just work". That's been the phrase Mac users have used long before Microsoft stole that (slogan) too.

[No Man]

Makes sense. And it would have been very difficult to pick up during testing with only a handful of prototypes assaulting the tower. If I recall correctly, a similar problem occurred when the iPod Touch first came out and started bombarding university wifi servers with DHCP requests, resulting in them being banned from the network. Apple really needs to look into large/wide scale testing methods for their products. It would solve a lot of these problems before they occur. But, of course, that might result in more products being leaked to the press, and Apple wouldn't want to kill that "new product frenzy" that they've cultivated.

I think the DHCP problem was determined to be a Cisco router problem, not an iPhone issue.

[Zimm2]

Hmm... most of the net is reporting that the 3G problems are primarily a result of poor network implementation. My guess is that you have two firms that are operating on different assumptions. The problem may be software, but it is just as likely the problem lies in how networks handle situations presented by the iPhone.

It will be interesting to see how this problem is resolved and where the true problem lies.

[templetonrl]

I went to the Apple store today- the 4th time in a week- with a problem of email not being fetched automatically. They restored my phone 3 times and each time it did not recognize that the phone had been restored and asked if I wanted to continue the restore which the Genius did 3 times. Finally they took my Macbook, turned it upside down, removed the battery and held the power button in for 30 seconds. They then activated my iphone as a new phone rather then a restore. That worked but they were unable to sync my music and photos so they uninstalled iTunes and then reinstalled it, then re-synced my phone and now I have music and pictures but the email still will not work. When they handed my Macbook back to me, there was a large scratch on the top cover, from where they had turned in over to remove the battery. Found out then that the employee that did this was not a genius just a helpful employee, who did the damage. They were going to replace my Macbook until they found out it was a 2.2 previous generation not the current 2.4. I then offered to pay the difference between my Macbook and a new Macbook Pro but the manager decided to order a new case for my Macbook meaning I will be without it for a while. I still want to pay the difference and get an undamaged computer so I am hoping for a positive outcome. I asked about returning the iPhone and was informed that only ATT has a 30 day return policy not Apple who has a 14 day return policy on all equipment. Apple stated I could terminate my ATT contract but could not return iPhone as the 14 days were up. I thought Apple was customer oriented but I am sorely disappointed.

[sciontcya]

Lord, some folks just can't be satisfied...

[brian.lee]

Apple should just go back to the release schedule they use to have with the old PowerPC computes. twice a year I think it was and the odd update. Is there really a need to release so frequently other then to appease share holders and analysts, which in the end is resulting in fault products? In the end you are pissing off the customers and giving yourself a bad name. I would much rather wait for the perfect product than have a fault product in my hand. Especially since you can't force iPhone users to upgrade firmware.

[smilin:)]

Shenanigans.

If the iPhone is instigating a tower problem why are other non-iPhone devices on the same tower not experiencing problems?

People have reported problems with iPhones while holding another 3G device side by side.

[Douglas W. Goodall]

Now that is the right question. The first and only question I have seen that gets directly to the issue at hand and it casts grave doubt on the whole explanation given about the iPhone causing the cell tower to run out of transmit power. If the cell tower ran out of transmit power, all other 3G devices would fail as well. If the current explanation is bogus, that means we are back to wondering if the chipset is the problem, and whether the phone can be fixed with a software upgrade. One possible explanation might be that other vendor's devices switch back to edge more gracefully when the tower runs low on transmit power and drops the connection. This is the first I have ever heard of a "user equipment" telling the cell tower how loud to transmit. I can see it telling the tower to "speak louder", but not to "shout" to start with. If AT&T is serious about forcing a ubiquitous upgrade to 2.0.2, they should disable 2.0 and 2.0.1 phones from operating at all, except for 911 calls. Otherwise we may be suffering for a year or forever with this problem because some people don't upgrade when asked. It is also not convenient for some people to upgrade, such as my father who is disabled in a hospital where they don't have Internet, and his phone and notebook will have to be physically transported to another location for the update, which is a hassle. Anyway, that was a Great Question.

[gefitz]

Apple is not into testing. They are into PR.

If they are late for a release, EVERYONE knows.

If they hit that release date, but the product has bugs, only the fanatic Apple-guy or early adopters know...and that's a lot smaller segment of the purchasing pool.

PR says get the product out ASAP and on schedule...and since PR is the driving force behind Apple, PR wins every time.

[bonesbautista]

I'd believe most of it. I still have my backup Motorola Z9. My mom has a Motorola V3xx and she lives nowhere near me in an area 50 miles from the nearest 3G area. Both Motos are SEEM-edited to disable the AMR-HR vocoder (a moot point in a 3G area). An investor I'm working with owns a ATT Tilt.

For the past 4 weeks, we have experienced dropped calls, poor voice quality, call failures, feedback (echo) - for me, on both phones when I SIM swap. The ATTWS stores in my mom's area don't carry the iPhone 3G. The Motos were rock-solid until 8/1; my mom didn't have one dropped call until then - two weeks ago, seven dropped calls in one week (none to me, all to landlines) from a GSM/EDGE only area.

I call certain areas regularly. Some calls to certain areas are perfect, every single time. Some calls to other areas are hit and miss. Some calls to certain areas are terrible, every single time. I've reported call problems to ATTWS, their field techs have dismissed my gripes. I had 3 dropped calls to one number yesterday, two the day before - to another ATTWS number...

It's not just the iPhone.

[Rants&Raves]

This is a bunk explanation; what AT&T is essentially saying is that the power request from the cell phone is honored in all cases based on trust. That means that anyone can take out the whole 3G network by sending repeated power requests beyond the tower's capacity. Easy enough for a bad guy to do.

The phone may request power, but the software at the tower should respond with what it deems appropriate, not with what it is asked.

[pjhenry1216]

Or it just realizes its an iPhone sending the request and grants it. it may be based off trust, but of the sender, not of what's being asked for. it may give a higher authoritative level to an iPhone after all, iPhone is probably a pretty big cash cow for AT&T. it got them a huge portion of apple's loyal fan base.

[Douglas W. Goodall]

I agree completely with you. The tower should obey the third law and look after its own survival. The theory of Internet Robustness says take more than fifty percent of the responsibility for the communication working correctly, but it doesn't say obey bogus requests without question.

[superswiss]

This would make sense. My Treo 750 started to have 3G reception problems around July, along with my coworker's Treos and Samsung Blackjacks around my office in Oakland, CA downtown. I forgot the exact date when it started. But all of our phones started to drop down to EDGE frequently. It was very noticable, because the EDGE frequencies interfere with many speakers. You know it switches to EDGE when you have the phone sitting on your desk and all of a sudden the desk phone speaker starts buzzing. We had constant speaker buzzing around here. I then went on vacation for the first two weeks of August and since I'm back, the problem is gone. We have full and reliable 3G coverage again. AT&T continued to dismiss these issues, but there was obviously a problem with their network. I just think non-iPhone owners weren't as vocal about the problem, but I firmly believe it affected everyone, given that all my coworkers started to have issues in an area where there was a high concentration of cell phones during the day. I never had issues at home, but I had issues in many areas of San Francisco as well.

[ilias_14]

@Tom

It is quite possible that the issue manifests itself when the number of devices connected to a given node is larger than any economically feasible field test.

@Rants&Raves

For Asynchronous CDMA (such as UMTS-based AT&T 3G network) the tower is required to distribute signal power evenly, but that depends on each device's location, surroundings etc. Only the device can provide that information by measuring signal on its side and communicate it with the tower.

[pjhenry1216]

Not sure if it affects the rest of what you said, but if I recall correctly, the AT&T 3g network uses GSM, not CDMA.

[skrubol]

@pjhenry
3G GSM, or UMTS uses WCDMA as it's underlying transmission scheme. Old GSM use TDMA.
Verizon and Sprint use CDMA2000 (I believe that's up to date,) which is another specific implementation of CDMA, which is probably what you're thinking of with CDMA vs. GSM.

[ESilverSki]

It seems pretty clear why they couldn't cover this in testing. If the problem is due to a combination of connection hogging and the amount of iPhone users, it would have taken testing far beyond what any company is capable of. There are likely hundreds of thousands iPhones in metropolitan areas like that in New York. No company has the capability to do this kind of testing, not even Apple.

[mulciberus]

There are more unanswered questions than the writer posits. Just one: Are the extraordinary calls for power that the phone makes passive or active? If active, service should be better at, say, 3:30 am, when common sense dictates the network is experiencing less use. Yet service is just as flaky at that hour.

Also, does this explain the multiple failures to send using AT&T's own SMTP server, even when connecting via wifi? I don't really think so. (Though, to be fair, this may be one of those other problems meant to be addressed in the 2.1 update the writer mentions).

[panda8888]

If this is to be true, why would it only affect Iphone reception - the non-upgraded phones power control issues should effect any 3G phone - not just Iphones

[pjhenry1216]

If this is the case, its still not really Apple's fault. I'm assuming AT&T gave Apple spec tolerances. AT&T should be aware of how much power a tower is capable of. It should then be aware of what this would mean to an individual phone and manufacturing of said phone. If this weren't an AT&T exclusive, I would lay the blame more on Apple's feet, but AT&T had way too much to do with production for them not to share the blame on this one. They had a relationship with Apple and I can't imagine a scenario where they wouldn't have seen this issue.

[Beeks1]

Ok, for now, i accept the excuse for too many phones not upgrading to 2.02 to get a decent 3g signal...but what about turning off 3g for any reason...and then to turn it back on...you have to do a reboot for the iphone to recognize the signal!!!! and then its still crap.

[rtuinenburg]

I think we are all due for a credit of some sort, either it be from apple or at&t.

[abavetta]

Is this saying that iPhone uses overload the cell phone towers? Hard to believe. Seems like cell tower radiated power or EIRP should be independent of users.

[sidepocketbr]

I do not believe this. I had no problems at all UNTIL I upgraded to 2.0.2
I called AT&T and they said the 2.0.2 upgrade has revealed additional weaknesses in the iPhone's chip.
I can ONLY use my phone in 3G areas, with no calling at all in an Edge zone,. Even texting is bad in Edge--I have to send the text 5 or 6 times before it will go through. But in 3G everything is okay.