A method controls the downlink beam in a radio communication system. The radio communication system has an antenna system with several antenna elements. The method involves a) examining a received uplink signal sent by a transmitter for the existence of phase correlations between parts of the uplink signal received from various antenna elements of the antenna system, and b) if a phase correlation is detected, assigning at least one source direction to the uplink signal and sending the downlink signal in the source direction. If a phase correlation is not detected, however, the downlink signal is sent in a non-directional manner in the form of several components produced using at least one diversity technique.