In a communication system comprising user equipment (UE) and a radio access network (RAN) comprising a plurality of cells is configured for receiving, by the UE, a radio resource control (RRC) information element (IE) indicating a high speed scenario (HST); and monitoring, by the UE in response to receiving the RRC IE indicating HST, a first number of frequency carriers that is reduced relative to a second number of frequency carriers monitored by the UE during a non-HST.