Reference signal design for wireless communication systems

A method comprising:

• receiving downlink control information (DCI) that includes an indication of a set of downlink resources and an indication of a modulation coding scheme, the set of downlink resources corresponding to a plurality of resource block (RBs) associated with a physical downlink shared channel (PDSCH) transmission;
• determining a phase noise reference signal density associated with the PDSCH transmission, wherein the phase noise reference signal density is determined based at least on the indicated modulation coding scheme;
• and
• receiving the PDSCH transmission via the set of downlink resources, wherein the set of downlink resources comprises a first subset of the set of downlink resources that is used for reception of one or more phase noise reference signals, the first subset of the set of uplink resources is comprised in a subset of the plurality of RBs, and the subset of the plurality of RBs that comprise the first subset of the set of uplink resources is determined based on at least a WTRU-ID.

A wireless transmit receive unit (WTRU), comprising:

• a memory;
• and
• a processor configured to:
• receive an indication of a set of resources and an indication of a modulation coding scheme, the set of resources corresponding to a plurality of resource block (RBs);
• determine a phase noise reference signal density, wherein the phase noise reference signal density is determined based at least on the indicated modulation coding scheme;
• and
• determine a first subset of the set of resources, wherein the first subset of the set of resources are associated with one or more phase noise reference signals, wherein the first subset of the set of resources is comprised in a subset of the plurality of RBs, and the subset of the plurality of RBs that comprise the first subset of the set of resources is determined based on at least a WTRU-ID.