baseband unit (BBU)

A baseband unit (BBU) is a component used in networks, on the Internet, in telephone networks and in radio base stations of mobile communications networks, among other things.

In radio base stations of mobile networks, the baseband unit is connected to the remote radio unit( RRU) or a remote radio head( RRH) via an optical fiber. The baseband unit communicates with the other radio modules via optical fiber and the Common Public Radio Interface( CPRI) physical interface.

Baseband Unit (BBU), photo: news.samsung.com

The baseband unit itself consists of a signal processor with which the voice signals to be transmitted are processed for radio transmission and the signals received from a mobile device. The baseband unit can also perform the switching functions of a mobile switching center. The RRU unit or remote radio head (RRH) connected to the baseband unit acts as a transceiver and provides the connection to the antenna.