There is proposed a mechanism for controlling and conducting a discovery procedure of small cells or secondary ceils located in a macro cell or primary cell. The discovery procedure is based on a discovery signal communicated via PDCH and based on a positioning reference signal (PRS). For configuring the signaling of the discovery signal, frequency domain multiplexing for splitting resources of the PRS in the frequency domain for increasing capacity, and/or usage of reserved communication resources for the signaling of the discovery signal are employed. Assistance information is provided to the UE for supporting the discovery of small cells.