Example integrated access systems, configuration methods, and baseband units are described. One example integrated access system includes a first baseband unit (BBU), a second BBU, a first data exchange unit, a first base station network management subsystem, a second base station network management subsystem, and a first pico remote radio unit (pRRU). The first BBU is connected to the first data exchange unit, the first BBU is connected to the first base station network management subsystem, the first BBU is connected to the second BBU, the second BBU is connected to the second base station network management subsystem, and the first pRRU is connected to the first data exchange unit.