1. A method for a user equipment (UE) operating in a wireless communication system, the method comprising:transmitting a random access preamble (RAP) on a physical random access channel (PRACH) resource in a radio frame;
calculating a random access-radio network temporary identifier (RA-RNTI) by considering a time-frequency resource associated with the PRACH resource and an index of a first radio frame of the PRACH resource;
monitoring a physical downlink control channel (PDCCH) identified by the calculated RA-RNTI for a random access response (RAR) reception during a RAR window; and
receiving the RAR in response to the RAP using the PDCCH identified by the calculated RA-RNTI,
wherein the calculating the RA-RNTI includes a modulo operation on the index of the first radio frame of the PRACH resource with a value related to a maximum RAR window size.