Method and apparatus to enable CSI reporting in wireless communication systems

A method performed by a base station in a communication system, the method comprising:

• transmitting, to a terminal, codebook configuration information for reporting of information associated with a precoding matrix indicator (PMI);
• and
• receiving, from the terminal, the information associated with the PMI for indicating a first amplitude coefficients pl(1) and second amplitude coefficients pl,i,m(2) identified based on the codebook configuration information,
• wherein, for each layer l=1, 2, . . . , v, each of two first amplitude coefficients pl(1) corresponds to each of a first group of coefficients and a second group of coefficients, and
• wherein a first group of coefficients includes a first subset of the second amplitude coefficients pl,i,m(2) with an index i=0, 1, . . . , L−1, and a second group of coefficients includes a second subset of the second amplitude coefficients pl,i,m(2) with an index i=L, L+1, . . . , 2L−1.

A terminal in a communication system, the terminal comprising:

• a transceiver;
• and
• a controller configured to:
• receive, from a base station, codebook configuration information for reporting of information associated with a precoding matrix indicator (PMI),
• identify first amplitude coefficients pl(1) and second amplitude coefficients pl,i,m(2) based on the codebook configuration information,
• transmit, to the base station, the information associated with the PMI for indicating) the first amplitude coefficients pl(1) and second amplitude coefficients pl,i,m(2),
• wherein, for each layer l=1, 2, . . . , v, each of two first amplitude coefficients pl(1) corresponds to each of a first group of coefficients and a second group of coefficients, and
• wherein the first group of coefficients includes a first subset of the second amplitude coefficients pl,i,m(2) with an index i=0, 1, . . . , L−1, and the second group of coefficients includes a second subset of the second amplitude coefficients pl,i,m(2) with an index i=L, L+1, . . . , 2L−1.

A base station in a communication system, the base station comprising:

• a transceiver;
• and
• a controller configured to:
• transmit, to a terminal, codebook configuration information for reporting of information associated with a precoding matrix indicator (PMI),
• receive, from the terminal, the information associated with the PMI for indicating a first amplitude coefficients pl(1) and second amplitude coefficients pl,i,m(2) identified based on the codebook configuration information,
• wherein, for each layer l=1, 2, . . . , v, each of two first amplitude coefficients pl(1) corresponds to each of a first group of coefficients and a second group of coefficients, and
• wherein a first group of coefficients includes a first subset of the second amplitude coefficients pl,i,m(2) with an index i=0, 1, . . . , L−1, and a second group of coefficients includes a second subset of the second amplitude coefficients pl,i,m(2) with an index i=L, L+1, . . . , 2L−1.