Mobile radio networks are radio facilities via which subscribers can communicate with each other on a mobile basis, i.e., regardless of their location. Like other networks, mobile radio networks consist of transmitting, receiving and switching equipment.
Historically, the first mobile communications networks were island networks that covered only a regional area by radio. Switching was done manually, with a radio channel being made available to the subscribers for the duration of the call. Later, switching was automated, analog transmissionwas replaced by digital transmission, and cellular networks took the place of island networks. Frequencies were also upgraded. Whereas transmission was initially carried out at 30 MHz and 80 MHz, the frequency increased via 150 MHz to 440 MHz, then to over 900 MHz and finally to 1,900 MHz and 2,200 MHz, which ultimately also enabled the subscriber density to be increased. This rapid mobile network development is referred to as generations.
The different generations of mobile communications networks
Mobile networks are assigned to generations, each of which represents a specific state of the art. The 1st generation (1G) is assigned to the A network that went into operation in Germany in 1971. At that time, the 1st generation mobile communications network was the world's largest interconnected mobile communications network, although it was still hand-switched. The B network followed a year later, also with analog transmission like the A network, but with fully automatic switching. This was followed in 1985 by the C network, a fully automatic, cellular network that operated in the 450 MHz range.
This was followed in 1992 by the first GSM networks, which can be counted among the 2nd generation (2G) mobile communications networks, and as early as 1993 by the first DCS networks. With the establishment and expansion of voice services, short message services, data services and fax services, and the launch of the satellite-based Iridium system in September 1998, mobile communications opened up new areas of application for mobile communications. The mobile communications systems of the 3rd generation (3G) are essentially characterized by UMTS.
Mobile communications networks of the higher generations
Beyond 3G defined two further generations: 3.5G and 3.9G, the latter of which was merged into the 4th generation (4G). Both 3G and 4G mobile communications networks are based on the UMTS infrastructure and feature significantly higher data transmission rates. 3.5G uses High Speed Downlink Packet Access( HSDPA) and High Speed Uplink Packet Access( HSUPA) and achieves data rates of around 20 Mbit/s, and 4G uses Long Term Evolution( LTE) or Ultra Mobile Broadband( UMB) and achieves data rates of 100 Mbit/s. The 4th generation technologies are all about high speeds of 100 Mbit/s and above, mobility and always being connected to the network: "Always Connected". These technologies include Evolution Data Optimized( EVDO), Mobile-WiMAX, iBurst, Ultra Wideband( UWB) and Long Term Evolution (LTE).
The chronological order continues with the 5th generation (5G): Namely, with the evolution of LTE networks toward LTE-A and toward higher LTE releases. 5th generation (5G) mobile networks are about data rates that are 30 times to 100 times higher than Long Term Evolution (LTE), i.e., data rates of up to 10 Gbit/s.
Mobile communications and mobile telephony are characterized by radio transmission from a stationary or mobile transmitter to a mobile receiver, a mobile device. The transmitter is referred to as the base station, the receiver as the mobile station. Depending on the radio orientation, the transmission area is a regionally limited area of a few kilometers in size. The size of the transmission area is essentially defined by the mobile communications concept and is directly dependent on the transmission power. If the individual transmitting areas are arranged as delimited areas, they are referred to as cellular networks; the transmitting areas are called radio cells. This contrasts with the coverage of a transmission area by trunked radio.