The invention relates to a method for operating a first and a second communication system, having a first and a second predetermined frequency band (13, 17), respectively, to be used for communication between a user terminal (4) and a node (2) of a cellular network (1), wherein the first communication system (11) has at least two narrowband channels (14, 15), which are distributed with a mutual spacing (16) over the first frequency band (13), and wherein the second communication system (12) has a set (18) of channel resources (19), which are distributed contiguously over the second frequency band (17), wherein the first and the second frequency band (13, 17) overlap, and communication is performed only in those channel resources (19) that do not overlap with the narrowband channels (14, 15), and wherein Enhanced Physical Downlink Control Channel (EPDCCH) and Demodulation Reference Symbols (DM-RS) are employed instead of the Physical Downlink Control Channel (PDCCH) and regular Reference Symbols (RS) of the LTE system. The invention further relates to a node of a cellular network for communication with the user terminal.