Here is the origin of the iPhone 3G problems
Apple has released in recent days the Firmware 2.0.2 for iPhone with the traditional and concise description "troubleshooting" at the same time for the spokesman Apple has publicly stated that the latest Firmware improves communication on 3G networks. In any case, iPhone 3G users around the globe have not experienced significant improvements even after updating the smartphone to Firmware version 2.0.2. A detailed explanation of the whole situation and technical reasons appeared on the RoughlyDrafted Magazine website: the source was a person very close to the AT&T operator who in the United States was the only one to market iPhone, always.
While remaining completely anonymous, the source of RoughlyDrafted Magazine appears immediately well informed and above all aware of the operating technologies of the 3G networks, for the latter the management of the signal strength of fundamental importance both for the performance of the connected devices, in this case iPhone 3G, both for the operation of the network as a whole. In practice, the signal strength management system inside the iPhone requires the antenna to which it is connected to have more power than is actually needed. If the number of terminals connected to the same cell increases, the transmitter can deplete its transmission power. When this occurs, the user of the device subject to falls during calls.
Continuing in his technical explanation, the anonymous source well aware of the things of AT&T also explains why iPhone users complain of performance below expectations. Once again the problem lies in the management of the transmission power: the higher the data transfer speed, the higher the transmission power required to the cell. IPhone 3Gs require more power than needed and, when high performance is needed, saturation of available transmission power is soon reached.
Updating the Firmware 2.0.2 solves the problem of managing the transmission power required by the iPhone 3G but, to be effective, all iPhone 3Gs must be updated to the new software. This is why according to the anonymous expert in the field, AT&T even sent SMS messages to iPhone users to inform them of the existence of Firmware 2.0.2 recommending their installation.
It is immediately evident that the detailed explanation of the anonymous expert clarifies in one fell swoop the two fundamental problems complained of by many users of the new iPhone: the drop in the line and the calls, and finally the disappointing performance on the 3G network. A technical problem is still identified which does not originate directly from the operators' 3G network alone or even from the single iPhone 3G, but from the joint operation of both in the management of transmissions between the cell and the smartphone. This means that the explanation just seen also confirms the tests performed in Sweden on iPhone 3G antennas that have shown results quite comparable to Nokia and Sony Ericsson terminals: see this Macity article.