Method and apparatus for reduced feedback MIMO

A base station (BS) comprising:

• a processor configured to:
• generate a configuration signal to configure a user equipment (UE) for selecting a transmission scheme, a codebook setting, and a reporting mechanism;
• and
• a transceiver operably connected to the processor, the transceiver configured to:
• transmit, to the UE, the configuration signal;
• transmit, to the UE, data with open-loop diversity;
• and
• receive a report including a first precoding matrix indicator (PMI) i1 on an uplink channel;
• wherein the first PMI i1 is calculated from a codebook that includes two PMIs i1 and i2 and is determined based on the codebook setting,
• wherein the reporting mechanism indicates a reporting of at least first PMI i1, and
• wherein the first PMI i1 includes at least two codebook indices i1,1 and i1,2.

A method for operating a user equipment (UE), the method comprising:

• receiving, by the UE, a configuration signal for selecting a transmission scheme, a codebook setting, and a reporting mechanism;
• in response to receipt of the configuration signal for selecting the codebook setting and the reporting mechanism and identifying that the transmission scheme indicates an open-loop diversity operation, calculating, by the UE, a first precoding matrix indicator (PMI) i1 from a codebook that is determined based on the codebook setting and includes two PMIs i1 and i2;
• and
• reporting only the first PMI i1 from among the two PMIs by transmitting the first PMI i1 on an uplink channel,
• wherein the reporting mechanism indicates a reporting of at least first PMI i1, and
• wherein the first PMI i1 includes at least two codebook indices i1,1 and i1,2.