A base station measures the uplink load on an uplink channel and controls the transmit timing of one or more mobile terminals on the uplink channel based on the measurements of the uplink load. The transmit timing of the mobile terminals may be controlled by sending timing control signals to the mobile terminals over a downlink control channel. In one embodiment, the transmit timing of the uplink channel is slaved to the transmit timing on a downlink channel. In this case, the uplink timing may be controlled by adjusting the downlink transmit timing.