Apparatus and method for communicating control data indicative of the capability of RF receiver equipment in wireless telecommunications devices. The control data is then used to allocate transmission resources to the telecommunications devices (including MTC-type terminals). Where a virtual carrier is established to carry data for a given MTC-type device, the position of the center frequency for that virtual carrier is assigned on the basis of both the capability of the RF receiver equipment of that terminal and the degree of traffic congestion on the frequency band at which the virtual carrier has been established.