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citizen band (CB)

The Citizen Band(CB) is a license-free, worldwide available ISM band in the range of 27 MHz, which is used for radiotelephony but also for radio mice, radio keyboards, baby monitors and for RFID.

The CB band is subject to legal regulations, which are monitored by the RegTP. These include the maximum permissible transmit power, the specified modulation methods, and the number of digitalchannels for telecopy( FAX) and packet radio. In addition, some radios are subject to registration and fees.

Channel frequencies in the CB band

Channel frequencies in the CB band

In Europe, the frequency range between 26.565 MHz and 27.405 MHz is reserved for CB radio. The channel sp acing is 10 kHz; thus, 80 channels are available. Amplitudemodulation( AM) and frequency modulation( FM) can be used as modulation. For amplitude modulation, the modulation code is A3E - which means: double sideband modulation, single channel, analog modulated with speech - and the permissible transmission power is 1 W; for frequency modulation, the modulation code is F3E - which means: frequency modulation, single channel, analog modulated with speech - and the transmission power is 4 W. The transmission can also be done as single sideband modulation( SSB/J3E) on some channels and also in the special mode Packet-Radio.

Since the 27 MHz band is available worldwide as a license-free frequency band, it supports two-way communications over short distances and radio transmissions in computer technology via Citizen Band Radio Services( CBRS).

Informations:
Englisch: citizen band - CB
Updated at: 28.02.2018
#Words: 229
Links: cell broadcast (SMS) (CB), integrated signal management (ISM), megahertz (MHz), radio frequency identification (RFID), power (P)
Translations: DE
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