Method for channel state information reporting in massive antenna system

At least one machine readable medium comprising a plurality of instructions that, when executed on a computing device, cause the computing device to carry out a method comprising:

• receiving, by a wireless transmit/receive unit (WTRU), a plurality of channel state information reference signal (CSI-RS) configurations;
• receiving, by the WTRU, information identifying a quasi-collocation (QCL) type for a subset of the plurality of CSI-RS configurations, wherein the subset of the plurality of CSI-RS configurations includes a first CSI-RS configuration and at least one second CSI-RS configuration, and wherein the first CSI-RS configuration corresponds to a first CSI-RS and the second CSI-RS configuration corresponds to a second CSI-RS;
• receiving, by the WTRU, an indication to use the first CSI-RS configuration for demodulation of a downlink (DL) data transmission;
• measuring, at the WTRU, a first set of QCL parameters associated with the identified QCL type by measuring at least the first CSI-RS and the second CSI-RS;
• measuring, at the WTRU, a second set of QCL parameters which are not in the first set of QCL parameters by measuring the first CSI-RS;
• and
• demodulating, at the WTRU, the DL data using the first and second sets of QCL parameters.

An apparatus, comprising:

• a processor;
• and
• memory storing a plurality of instructions that, when executed by the processor, cause the processor to:
• receive, by a wireless transmit/receive unit (WTRU), a plurality of channel state information reference signal (CSI-RS) configurations;
• receive, by the WTRU, information identifying a quasi-collocation (QCL) type for a subset of the plurality of CSI-RS configurations, wherein the subset of the plurality of CSI-RS configurations includes a first CSI-RS configuration and at least one second CSI-RS configuration, and wherein the first CSI-RS configuration corresponds to a first CSI-RS and the second CSI-RS configuration corresponds to a second CSI-RS;
• receive, by the WTRU, an indication to use the first CSI-RS configuration for demodulation of a downlink (DL) data transmission;
• measure, at the WTRU, a first set of QCL parameters associated with the identified QCL type by measuring at least the first CSI-RS and the second CSI-RS;
• measure, at the WTRU, a second set of QCL parameters which are not in the first set of QCL parameters by measuring the first CSI-RS;
• and
• demodulate, at the WTRU, the DL data using the first and second sets of QCL parameters.