Method and device for receiving PTRS for cancelling phase noise in wireless communication system

A user equipment (UE) operating in a wireless communication system, the UE comprising:

• a transceiver configured to transmit and receive signals to and from a base station (BS);
• and
• a processor connected to the transceiver,
• wherein the processor is configured to:
• receive modulation and coding scheme (MCS) information for each of two or more codewords from the BS;
• determine a phase tracking reference signal (PTRS) antenna port that is mapped to a demodulation reference signal (DMRS) antenna port among a plurality of DMRS antenna ports for the two codewords based on the MCS information,
• wherein, when the two codewords have a different MCS, the processor determines that the PTRS antenna port is mapped to a DMRS antenna port with the lowest index among one or more DMRS antenna ports for a codeword with the highest MCS among the two codewords, and
• wherein, when the two codewords have the same MCS, the processor determines that the PTRS antenna port is mapped to a DMRS antenna port with the lowest index among one or more DMRS antenna ports for the two codewords;
• and
• receive a PTRS based on the determined PTRS antenna port.