We use our mobile devices for so many things today; to make calls, to send texts, emails and pictures, and for shopping, banking, sharing, listening, learning and downloading.
Our mobile devices use radio waves to do all of these things. We explain on this page how your mobile device works, why mobiles need base stations and what radio waves are.
How does your mobile device work?
When using your mobile device to go online, you can access content either through your mobile network or via a wireless (WiFi) access point. Your choice is communicated automatically to your mobile network using radio waves.
Your mobile device transmits your request to access certain content as radio waves, converting them into electrical signals through a network of base stations and cables to the core switching centre. This time, the switching centre acts as a gateway – either sending content directly to your device or enabling content to be sent from other content providers.
The web content is sent out from the switching centre as electrical signals to your nearest base station. This then transmits the signals to your mobile device. Your mobile receives the communication and converts it back into text, pictures, sound or video.
The short answer is they don’t. Mobile devices need the antennas that sit on top of masts to relay your communications. Masts simply act as a support structure holding the antennas in place. Placing antennas high up prevents signals from becoming weaker due to the presence of obstacles such as buildings or the local landscape (known as ‘attenuation’). This helps to ensure your mobile device works as quickly and efficiently as possible.
Radio waves explained
Electromagnetic fields are invisible and can be found all around us. They can occur naturally – for example, from the sun – and are also generated by our everyday use of electricity at home and at work.
Electromagnetic fields are not all the same. They are part of a spectrum and are divided into two main categories: ionising or non-ionising radiation, determined by the energy contained in them.
The diagram below shows different frequencies and divides them into ionising and non-ionising groups. As you can see, radio waves used by mobiles and their masts, as well as remote controls, radios and baby monitors, are classified as non-ionising.
The effects of exposure to these electromagnetic fields vary along differing parts of the spectrum. Ionising radiation can damage the structure of cells, while non-ionising radiation principally has a heating effect. Heating from non-ionising radiation can cause immediate harm if sufficiently intense (for example, the heat from an electric fire can cause burns), but it has not been shown to have longer-term ill effects.
To ensure people are protected, different regulations will apply depending on which frequency is being used.
Authorities including the World Health Organization (WHO) agree there is no evidence that convinces experts that exposure to electromagnetic fields produced by radio waves from mobile devices and base stations operated within guideline limits has any adverse health effects.
Electromagnetic fields in our daily lives
Most of our everyday electrical appliances produce electromagnetic fields while we use them: from refrigerators, hairdryers and toasters to computers, microwaves and wireless technology (such as WiFi, remote controls and mobile phones). These appliances generate or use frequencies that are categorised as non-ionising radiation.
Wireless technology is subject to international guidelines set by the International Commission on Non-Ionizing Radiation Protection (ICNIRP).
Many national governments have produced regulations in line with the ICNIRP guidelines, and introduced regular monitoring. In some countries, such as India, stricter regulations than the ICNIRP guidelines have been implemented.
vodafone_infographic_EMF_ST6_v7Size: 5 MB Download
How do radio wave frequencies differ?
Radio waves ‘vibrate’ at different frequencies, making them useful for different applications, and this spectrum of waves is divided into bandwidths for different uses.
The different frequencies that mobile networks use are auctioned off and bought by different mobile companies to provide the service that customers want.
Allocation of global radio frequencies and satellite orbits is coordinated by the International Telecommunications Union (ITU) – a United Nations specialist agency.
Radio spectrum can be used for different reasons and to enable different technologies, including mobile and wireless broadband communications, maritime services, aeronautical communications and navigation, television and sound broadcasting, radio navigation and satellite systems, emergency communications and disaster relief, intelligent transportation systems and climate change monitoring.
ITU’s Master International Frequency Register records the use of spectrum by radio communication stations worldwide to provide international recognition and protect against signal interference. The agency also develops the technical standards to ensure networks and technologies interconnect seamlessly.