A UE receives a first configuration identifier for generating downlink PRSs or CSI-RSs. The first configuration identifier is an integer in a first range that includes a second range in which a scrambling identifier for generating a CSI-RS is. The UE receives modulation symbols on a set of resource elements allocated for carrying reference signals in an OFDM symbol in a slot in a radio frame. The UE generates a seed of a pseudo-random sequence for deriving the reference signals on the set of resource elements based on a wrapping result of a first output of a function using the first configuration identifier as a parameter and an offset. A second output of the function using a second configuration identifier as a parameter is the same as the first output. The second configuration identifier is in the second range and corresponding to the first configuration identifier.