A centralized controller determines n radio remote units (RRUs) in m RRUs, where a sum of first downlink reference signal received powers (RSRPs) of a same terminal, corresponding to the n RRUs, is greater than or equal to a first preset value, and a first downlink RSRP of one terminal corresponding to one is a received power that is estimated by the centralized controller, that is measured by the terminal, and that is of a reference signal (RS) from the RRU at a corresponding first RS transmit power. The centralized controller turns off an RRU that is in the m RRUs and that is different from the n RRUs, boosts a second RS transmit power corresponding to each of the n RRUs to a corresponding first RS transmit power, and enables each of the n RRUs to send an RS at the corresponding first RS transmit power.