Methods, Apparatuses, and Computer Software Products for Processing in MIMO System

A method, comprises:

• receiving codebook-based training information;
• selecting the best precoder in accordance with said codebook-based training information;
• sending precoding index reports to the base station, said precoding index reports including index of said best precoder;
• receiving beamformed channel state information reference signal from said base station;
• sending channel state information in accordance with said beamformed channel state information reference signal to said base station.

A first apparatus, comprises:

• at least one processor;
• and
• at least one non-transitory memory including computer program code,
• the at least one memory and the computer program code configured to, with the at least one processor, cause the first apparatus to perform operation of at least the following:
• send codebook based sweeping information to at least one user equipment;
• receive precoding index reports from said at least one user equipment;
• group said at least one user equipment into at least one groups, wherein the user equipments in the same group are covered by the same transmitting precoding;
• send beamformed channel state information reference signal in accordance with said at least one group;
• receive channel state information reports from user equipments of said at least one group, so as to transfer data to said at least one user equipment accordingly.

A second apparatus, comprises:

• at least one processor;
• and
• at least one non-transitory memory including computer program code,
• the at least one memory and the computer program code configured to, with the at least one processor, cause the second apparatus to perform operation of at least the following:
• receive codebook-based training information;
• select the best precoder in accordance with said codebook-based training information;
• send precoding index reports to said base station, said precoding index reports including index of said best precoder;
• receive beamformed channel state information reference signal from said base station;
• send channel state information in accordance with said beamformed channel state information reference signal to said base station.

A computer program product comprising a non-transitory computer-readable medium storing computer program code thereon which when executed by a device causes the device to perform at least:

• send codebook based sweeping information to at least one user equipment;
• receive Precoding Index reports from said at least one user equipment;
• group said at least one user equipment into at least one groups, wherein the user equipments in the same group are covered by the same transmitting precoding;
• send beamformed channel state information reference signal in accordance with said at least one group;
• receive channel state information reports from user equipments of said at least one group, so as to transfer data to said at least one user equipment accordingly.

A computer program product comprising a non-transitory computer-readable medium storing computer program code thereon which when executed by a device causes the device to perform at least:

• receive codebook-based training information;
• select the best precoder in accordance with said codebook-based training information;
• send precoding index reports to said base station, said precoding index reports including index of said best precoder;
• receive beamformed channel state information reference signal from said base station;
• send channel state information in accordance with said beamformed channel state information reference signal to said base station.