Why iPhone 2.0.2 fixed problems for some users

Stephen Withers
Friday, 29 August 2008 02:22

Your IT - Mobility

When Apple released the 2.0.2 software for its iPhone 3G, a proportion of users found it improved connectivity and reduced the number of dropped calls. Others reported no difference. What's going on?

A new report explains that one of the changes in the 2.0.2 software altered the way the iPhone 3G demands signal power from the cell tower.

According to Roughly Drafted, a "source close to AT&T" reportedly claimed that a faulty power control algorithm caused iPhone 3Gs to request more power than was necessary.

If sufficient handsets in a given cell do this, the aggregate demand exceeds the available power and some handsets will drop calls as a result.

Similarly, high data rates require more transmission power. If handsets are already asking for more power than necessary, there is no headroom to deliver data at the higher speeds.

This is where things get interesting. Roughly Drafted's source said: "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."

So why does the updated software help some users and not others? Find out on page two.