A Remote Radio Unit (RRU), also known as a Remote Radio Head (RRH) is a transceiver deployed on base stations. A transceiver combines the functionality of both a transmitter and receiver in one unit. Due to its features, RRU is used as a transceiver in telecommunications.
Baseband refers to a communication channel that carries digital signals over a single frequency range. Unlike broadband, which uses multiple channels to transmit signals simultaneously, baseband utilizes the entire bandwidth for a single signal.