Basics of radio - BfS

Mobile communication involves the use of high-frequency electromagnetic fields to wirelessly transmit voice and data over long distances. These fields propagate as waves at the speed of light, carrying energy and information. The evolution of mobile communications technology has progressed through several standards. The first fully digital mobile telephone networks used in Germany, operational since the early 1990s, are based on the GSM (Global System for Mobile Communications) standard, utilizing frequencies around 900 MHz and 1800 MHz. Subsequently, the third generation (3G) mobile networks operated via the UMTS (Universal Mobile Telecommunications System) standard from 2004 to 2021, using frequencies between 1920 and 2170 MHz. LTE (Long Term Evolution) technology succeeded UMTS, sometimes referred to as 3.9G, with LTE-Advanced meeting the criteria for true fourth-generation (4G) mobile communication systems. LTE has been available in Germany since 2010, with LTE-Advanced introduced in 2014. The latest advancement, 5G, has been available since 2020, enabling new applications such as autonomous vehicles, voice-activated assistants, and smart appliances by offering significantly higher data transmission speeds. Mobile terminals that use these technologies include traditional mobile phones, smartphones, routers, and tablet computers capable of establishing mobile radio connections. These devices generate the high-frequency electromagnetic fields necessary to communicate with mobile base stations. Concerns have been raised about exposure to these fields from base stations and user devices, which is the focus of radiation protection studies. The Bundesamt für Strahlenschutz (BfS) provides comprehensive information on these basic aspects of mobile communications, including the standards, technologies, and exposure considerations related to this ubiquitous wireless communication method.