There is provided a communication device and a base unit, and methods thereof, for determining control information. The communication device receives a control channel message associated with the communication device in a control region on a first carrier from a base unit. The communication device also determines a set of resources in a search space within the control region, attempts to decode the set of resources in the search space for the control channel message, and determines control information from the decoded control channel message. The base unit generates a control channel message comprising control information associated with the communication device, determines a set of resources in a search space within a control region, selects a subset of resources within the determined set of resources for transmitting the control channel message, and transmits the control channel message on the selected resources in the control region on a first carrier.