How mobile communications work
Today, we take it for granted that we can make calls or send data anytime, anywhere. What technology makes this possible?
Electromagnetic fields – the foundation of mobile communications
Electromagnetic fields are a natural phenomenon; for example, even light is made up of them. An electromagnetic field travels in waves at the speed of light, carrying energy as it moves. Mobile telecommunications use electromagnetic fields to transmit voice and data.
Radio waves – Carrying information for radio, television, and mobile communications
Electromagnetic fields can be generated using technology. They also occur naturally wherever electricity flows – for example, in everyday devices like hairdryers, electric razors, or televisions. In mobile communications, these fields are intentionally created to transmit information.
When electromagnetic fields spread out, they are called radio waves. Technology distinguishes between them based on their frequency, field strength, and signal shape.
Base stations – The hubs of the mobile network
To make mobile calls from anywhere, we rely on a large number of mobile base stations. Each one has both a transmitter and a receiver.
When you make a call, your phone connects wirelessly to the nearest base station. The station’s receiving antenna picks up the signals and forwards them via cable or microwave link to the nearest mobile switching center. There, the call is transferred to the fixed network and routed to the required telephone line. If the called party is also using a mobile phone, the call is routed from the fixed network via a mobile switching center and the nearest base station to their mobile phone.
Radio cells - comprehensive coverage in urban and rural areas
Each base station can only handle a certain number of calls simultaneously and transmit a certain volume of data. It therefore serves a relatively limited area, known as a radio cell.
Radio cells vary in size depending on the anticipated number of users and the mobile communications frequencies used. Since most people make calls and use data in cities and towns, there are more base stations with smaller radio cells in these areas to provide optimal mobile coverage.
Small cells for more capacity
Mobile data usage is especially high in busy places like pedestrian zones, train stations, or public transit stops. That’s why we’re building more small cells in these locations – they fit seamlessly into existing infrastructure and strengthen the overall mobile network. They can be mounted on public phone booths, building walls, and street furniture such as advertising pillars.