How does mobile telephony work?

People want to be able to use their mobile phones anywhere. Now that mobile devices such as smartphones, tablet PCs and tablets offer more than just making calls, it has become quite usual to surf the internet, make video calls and download photos, music and videos.

Applications for video calls, internet surfing, social networks or downloads require greater power from the networks. In order to increase capacity, networks need to develop and expand.

 

Mobile networks

Mobile networks have a complex technical infrastructure, which is the design and responsibility of the mobile network operators. In Germany, four operators provide their own GSM and UMTS networks in addition to the new LTE networks under construction.
GSM and UMTS provide the standards for the technology used in more than 232 countries. Over five billion people worldwide use one of these two standards. In contrast to these networks, which employ different standards in America, Europe and Asia, the new LTE standard, introduced in 2010, is the first mobile technology that is globally standardized. 

Cell sites and base stations

The key to modern mobile telephony is its sophisticated technology. It guarantees both high transmission quality and constant coverage, made possible because of the cellular structure of the networks. They consist of many interconnected cell sites; each one served by a transceiver which both transmits and receives signals. This is what we know as a mobile phone base station.

Mobile phone base stations

Because calls are always made between the phone and the closest base station of the network operator, mobile phones can be used anywhere.
Each base station provides the radio cell with a signal. At the same time, it registers those mobile phones from its network that are operating within the area. This data enables each mobile phone to be located automatically anywhere in the world within seconds, so connections are fast.

Radio waves

The physics of mobile telephony is based on high-frequency electromagnetic radio waves. These are the medium of transportation, carrying information at the speed of light from the mobile phone to the closest base station. Speech and data are digitised, broken into small units and transformed into radio waves before they can be transmitted.

Transmission

The mobile phone base station receives radio signals from a mobile phone and transmits them via a cable or radio connection to a distant switching centre operated by the network. From there, calls are forwarded to the receiver and connections are made.
 

 

 

 

State: January 2012