iPhone 3G Issues: The Plot Thickens

The iPhone 3G’s problems are a hot topic of discussion these days, with everyone trying to figure out who’s to blame. Is it the fault of the carrier? The software? Or the chips inside the device? While I have a feeling this is really a witches’ brew of all three, the explanations only add to the mystery.
Users are complaining of four basic problems. And notably, they are the same ones that handset makers and carriers in Europe and Asia had to deal with when they started to roll out 3G systems in those regions:

1- Speed of the 3G network is often not as fast as it should be.
2- Switching between the EDGE and 3G networks leads to broken web sessions.
3- For some, the switch between the networks leads to dropped calls.
4- Weak battery life.
A report on BusinessWeek.com today sheds more light on the issue, though there is still no official comment from Apple. According to the report, the problem is impacting 2-3 percent of iPhone traffic. BW cites an unnamed source who notes that considering 1 percent of AT&T calls get dropped, this is a problem, but not a catastrophe.

AT&T: Network Is Fine

AT&T, displaying a classic head-in-the-sand attitude, issued a statement that said, “Overall, the new iPhone is performing just great on our 3G network.” Right, and overall, the Yankees are on target to win the MLB World Series! If it’s performing so well, why are so many people complaining?

Ask anyone in San Francisco or New York and they will make your ears bleed with their tales of iPhone 3G woes. When we asked our readers about their experience, a majority said they were getting speeds only marginally better than the original iPhone. BW offers some clues as to what the problem might be:

Part of the role of the Infineon chip is to check whether there’s enough 3G bandwidth available in a given area. If 3G isn’t available or there isn’t enough bandwidth, the iPhone will be shifted to a slower network. One source says Apple programmed the Infineon chip to demand a more powerful 3G signal than the iPhone really requires. So if too many people try to make a call or go on the Internet in a given area, some of the devices will decide there’s insufficient power and switch to the slower network—even if there is enough 3G bandwidth available.

Apparently this is resulting in problems in areas of high iPhone density — aka San Francisco, Boston etc. — the very markets where Apple has both a strong retail presence and higher-than-average mind share.

Antenna & Weak Signals

Meanwhile, Swedish magazine Ny Teknik is citing unnamed experts that have come up with yet another theory:

… the most likely cause of the 3G problems is defective adjustments between the antenna and an amplifier that captures very weak signals from the antenna. This could lead to poor 3G connectivity and slower data speeds.

And when I tried to test their theory, it made sense. I currently have three 3G handsets — Nokia E71, Nokia N78 and Sony Ericsson U750a — all of which are optimized for the AT&T 3G network. The speeds on those phones are much faster. Similarly, if I pop a 3G SIM card into one of the USB modems, the speeds on AT&T network are quite fast.

Its the 3G Stupid

Finally there is our friend Mike Puchol, who explains how wireless networks work and outlines some of the problems associated with 3G technologies. In his view, the problem is shared bandwidth:

…key issue to remember is that the download rate is “per tower”, not per user. So, if two users using HSDPA are on the same tower, they will each get a maximum throughput of 3.6Mbps. Divide even further, and the more users you have the worse experience everyone gets.

His explanation also makes sense, and ties in with an earlier post of mine in which I looked at the backhaul problems facing U.S. 3G networks and asked whether or not they’d be able to withstand the iPhone 3G stress test.