Method and apparatus for controlling RI report

A method, in a UE in an LTE cellular communication network, the method comprising:

• receiving RRC signaling indicative of a CSI report set, wherein RRC signaling and/or additional DCI signaling is further indicative of:
• (i) a restriction of a precoding codebook subset for each CSI process in the CSI report set;
• or
• (ii) a rank for each CSI process in the CSI report set;
• and
• determining a rank characteristic of CSI feedback in accordance with:
• (i) the restriction of precoding codebook subset for each CSI process in the CSI report set;
• or
• (ii) the rank for each CSI process in the CSI report set.

A base station in an LTE cellular communication network, the base station comprising:

• a processor configured to determine a report set comprising a plurality of CSI processes for a UE, wherein each CSI process is defined with one part of NZP RS resource for channel measurement and one part of IMR for interference measurement;
• and
• a transmitter configured to send RRC signaling indicative of the CSI report set to the UE,
• wherein the RRC signaling and/or additional DCI signaling is further indicative of restriction of:
• (i) a precoding codebook subset for each CSI process in the CSI report set;
• or
• (ii) a rank for each CSI process in the CSI report set.

A UE in an LTE communication network, the UE comprising:

• a receiver configured to receive RRC signaling indicative of a CSI report set, wherein the RRC signaling and/or additional DCI signaling is further indicative of:
• (i) a restriction of a precoding codebook subset for each CSI process in the CSI report set;
• or
• (ii) a rank for each CSI process in the CSI report set;
• and
• a processor configured to determine the rank characteristics of CSI feedback in accordance with:
• (i) the restriction of precoding codebook subset for each CSI process in the CSI report set;
• or
• (ii) the rank for each CSI process in the CSI report set.