LTE accommodates data traffic on the network with a system other than the 3G. So at least at an early stage, many operators have chosen to handle the usual phone calls with a hybrid system between LTE and old systems (“CS Fall Back”). In practice, when you make or receive a phone call on their smartphone is brought to the LTE network to 2G or 3G, over calling the system automatically the phone over LTE. In future calls will be handled directly on LTE, via data traffic (a bit like when you make a call with Skype).
The availability of LTE Italian national territory was not immediate and won’t be complete for one simple reason: to be able to distribute the new network is necessary to install new antennas. The operators are working hard to build new ones and, where possible, to include them in the existing repeaters without additional environmental impacts.
In Italy the Government has finished the race in September 2011 for the frequency assignment for LTE in 800, 1800 and 2600 MHz. The operation did collect some State billion: Telecom Italy alone has invested more than 1.2 to scan frequencies. Starting from the beginning of the year have been made available in 800 MHz frequencies, the other will be added to allow for more and better coverage of the national territory. In recent months there has been controversy over whether the new system may interfere with the frequencies of digital cable, but the tests so far conducted the problem seems to be very limited and fixable with some special filters to be used on the affected television systems (there is a fund involving the operators to manage the intervention).
Due to the somewhat chaotic evolution of telecommunication systems over cellular networks around the world, there are no standard frequencies for data transmission over LTE. Each country has adopted its own rules and this complicates life especially those who make the devices, which must try to insert LTE systems compatible with as many frequencies as possible. This means that it is not said that a smart phone that receives over LTE in a given country to operate in another.