Basically imagine you are driving down a motorway making a call. You connect to the nearest mast but often also connect to 1, 2 maybe even 3 further away. Then when you lose signal on the closest mast, your call switches to the 2nd mast and so on.
Also. In cities etc the nearest mast is often at capacity so the phone and network needs to be aware of nearby masts. In this case the phone makes the call via a mast further away which is not at capacity.
In cities you often see an o2 mast ontop of one building. You then see an o2 mast on the building next door. It's not for coverage - it's to ensure capacity.
see my other reply, I do not think this is causing an issue personally. It's how the technology works.
If the phone only connected to one mast at a time. As you were driving, you would connect to your local mast and make a call. This signal would then be lost as you drove away from the mast... The phone would then go searching... and find the next mast. Not ideal at all. At virtually anytime the phones aware of the masts around it. Even if the phones not aware, the network has so much control also over routing its calls.
It's why the T-Mobile / Orange merger is a bit of a mess currently (although being sorted). You know with it you can use orange & t mobile signal...
Essentially as it stands switching between a T-mobile mast and an Orange mast requires a total loss of service as the switch is made. So if you are making a call on orange and then enter a t-mobile only area, the call is dropped as the signal switches to T-mobile. So it can appear that calls are dropping even when the signals good.
With the 4G rollout everything essentially being turned into a T-mobile mast. The orange masts will get upgraded. This will mean that there will no longer be two separate networks so the switchover will in time work seamlessly. Long way to go though.
You're almost always connected to a number of masts. Even your nearest mast often has 2, 3 or 4 transmitters for your network all pointing different directions - so you can be connected to multiple masts both on the same tower.
Edited by ukhardy07 (Mon 15-Jul-13 04:27:50)