Difference between BBU and RRU

Hello, user_3872283.
The RRU technology divides a base station into two parts: a master unit (radio server) and a remote unit (RRU). The two parts are connected through optical fibers. The RRU interface is based on the open CPRI or IR interface and can be used to stably connect to devices of mainstream vendors. The RS can be installed in a proper position in the equipment room, and the RRU is installed at the antenna end. In this way, a part of the previous base station module is separated. By separating the RS from the RRU, the maintenance work can be simplified to the RS end. One RS can be connected to several RRUs, which saves space, reduces the setting cost, and improves networking efficiency. At the same time, the interface between the two is connected by using an optical fiber, which reduces loss.

Distributed base stations are widely used in 3G networks. Therefore, optical fibers are required between RRUs and BBUs. One BBU supports multiple RRUs. The BBU+RRU multi-channel solution is used for the BTS-BBU to provide indoor coverage for large stadiums.