A heterogeneous radio access network (20) comprises a macro layer (22) including at least one macro base station (24) and a micro layer comprising at least one micro base station (26). In an example embodiment a base station node comprises a scheduler (40) and a communication interface (42). The scheduler (40) is configured to prepare a subframe for transmission over a radio interface by configuring the subframe to include a micro layer downlink control channel region in addition to a macro layer downlink control channel region. The communication interface (42) is configured to transmit at least the subframe over the radio interface.