B-Netz

The B - net was an analog mobile radio system to 1994 from 1972 in operation. It replaced the A- grid and was in turn replaced by the C network.

The B line was opened on 14 January by the intervention of the radio communication range Zeven. A significant revision of the mobile network was the ability Selbstwählverbindungen in both directions, from the telephone network to the cellular network and vice versa, to produce. That made a substantial progress compared to the A network that was accessible only through exchanges. The B - network worked until 1980 with 38 voice channels. By extension, to 75 voice channels in 1980 from the B network, the B/B2-Netz. This reached in 1986 with 158 base stations and 27,000 participants its highest development level and at the same time the maximum number of participants. On December 31, 1988, the B/B2-Netz had nationwide still 24 382 participants. To the west of Berlin there were still 1,078 participants. The B/B2-Netz was shut down on 31 December 1994.

A serious problem of B/B2-Netzes was that had to know the location of the mobile phone to connect to a mobile phone of the caller, that is, he had to know, in the catchment area ( about 27 km ) which base station was located the phone, and select a corresponding code. The Federal Republic of Germany was divided in to 150 zones (diameter up to 150 km). You knew, for example, that the subscriber moves in the Munich area, we chose first the code from Munich ( 089 ), then the digits " 05", then the local number. When changing the coverage area of ​​the talks, however, were interrupted and had to be rebuilt.

In the limited context of roaming was possible in the neighboring countries Austria, the Netherlands, Luxembourg.

The transmission between the base station and the mobile phone was analog and unencrypted; anyone who owned a radio with an appropriate reception area could overhear. For encryption, both participants had to use additional devices, which have been applied only in rare cases, such as discussions of important politicians.

As technical development, the C network was put into operation on 1 May 1985, which brought numerous advantages compared to B/B2-Netz.

Specifications

  • First 16,000 participants, according to an extension of the radio channels 27,000 participants were possible
  • The highlight of the network:
  • Voice channels:
  • Frequency ranges:
  • 4.6 MHz duplex spacing
  • Channel spacing: 20 kHz
  • Bandwidth per channel: 14 kHz
  • Modulation method: FM, 4 kHz frequency deviation
  • Transmitting power:
  • Limited roaming in the countries of Austria, the Netherlands and Luxembourg
Mobile telephony C-Netz
94942
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