Network coverage issues

A mobile phone call, like a trapeze
artist, gets passed from one trapeze
(antenna) to another. If there isn't
anyone on the receiving end,
the call - like the trapeze drops.

Because radio waves travel through open spaces, mobile phone connections can sometimes be interrupted even within a cell. Things such as bad weather, large buildings or other objects between the caller and the nearest radio tower or base station can affect mobile phone calls.

Another thing to be mindful of is the mobile phone carrier. The carrier is a company that provides the telecommunications service. Because each carrier will have their own base stations accountable to them, not all carriers will offer the same network coverage.

If you have used a mobile phone, you might have had your conversation cut short when your phone disconnected from the network for an instance. This is called a dropped call.

A dropped call usually occurs when you are moving between cells while on the call, and there are not enough antennas for your call in the area you are travelling through. Because your call can no longer be passed on from one antenna to another, it gets dropped.

There are four factors that affect the quality and completion of a mobile phone call:

Network architecture

This refers to where the antennas are located. If a mobile phone user was travelling to a remote area, there may not be enough antennas - or any antennas at all - for his or her call to be transferred to. For instance, when you drive through parts of Australia, there are places where there is no reception.

Topography

This refers to the landscape and architecture of the surroundings, such as trees and tall buildings. When the line of sight between your phone and the radio tower is broken, the mobile call can suffer. Objects and features such as hills, trees and tall buildings can affect a mobile call.

Capacity

This refers to the number of callers that are using the frequencies in one cell at any given time. If there are too many callers using one cell, there will not be enough voice channels to go around. When that happens, callers not getting through will hear a busy signal.

This is why many people can't get through on their mobile phones during crises, at major sporting events or festivals. Have you ever tried sending a text message or making a mobile call in the middle of a crowded city at midnight on New Year's Day? Chances are, you would have had to try several times before you got through, because everyone was trying to wish people a Happy New Year!

Power-to-tower failure

This is not very common, but sometimes radio towers can lose power, which in turn affects the mobile network and the mobile phones using it. Blackouts (power outages) and natural disasters like cyclones can affect your mobile call. So, just because your mobile phone has its own battery doesn't mean it doesn't need the electricity grid to be working!