A method for transmitting channel state information, CSI, by a user equipment, UE, in a wireless communication system, comprising: receiving, from a base station, configuration information for a parameter set according to a rank value through a higher layer signaling, receiving (S20010) a channel state information reference signal, CSI-RS, from the base station through a multiple antenna port; and reporting (S20020) the CSI to the base station, wherein the CSI includes a precoding matrix indicator, PMI, for a linear combination based codebook, wherein the codebook is configured based on the parameter set which is i) a parameter set for rank 1 and rank 2 or ii) a parameter set for rank 3 and rank 4, wherein a number of first bits and a number (L) of first combining beams for each layer is related to the codebook based on the parameter set for rank 1 and rank 2, and a number of second bits and a number (L) of second combining beams for each layer is related to the codebook based on the parameter set for rank 3 and rank 4, wherein, based on the parameter set for rank 1 and rank 2: the number (L) of first combining beams is equal to four, and the number of first bits is equal to three and is respectively related to first amplitude coefficients and first phase coefficients related to the codebook, and wherein, based on the parameter set for rank 3 and rank 4: the number (L) of second combining beams being equal to two, and the number of second bits amounts to two and is respectively related to second amplitude coefficients and second phase coefficients related to the codebook. receiving, from a base station, configuration information for a parameter set according to a rank value through a higher layer signaling, receiving (S20010) a channel state information reference signal, CSI-RS, from the base station through a multiple antenna port; and reporting (S20020) the CSI to the base station, wherein the CSI includes a precoding matrix indicator, PMI, for a linear combination based codebook, wherein the codebook is configured based on the parameter set which is i) a parameter set for rank 1 and rank 2 or ii) a parameter set for rank 3 and rank 4, wherein a number of first bits and a number (L) of first combining beams for each layer is related to the codebook based on the parameter set for rank 1 and rank 2, and a number of second bits and a number (L) of second combining beams for each layer is related to the codebook based on the parameter set for rank 3 and rank 4, wherein, based on the parameter set for rank 1 and rank 2: the number (L) of first combining beams is equal to four, and the number of first bits is equal to three and is respectively related to first amplitude coefficients a number of first bits and a number (L) of first combining beams for each layer is related to the codebook based on the parameter set for rank 1 and rank 2, and a number of second bits and a number (L) of second combining beams for each layer is related to the codebook based on the parameter set for rank 3 and rank 4, wherein, based on the parameter set for rank 1 and rank 2: the number (L) of first combining beams is equal to four, and the number of first bits is equal to three and is respectively related to first amplitude coefficients the number (L) of first combining beams is equal to four, and the number of first bits is equal to three and is respectively related to first amplitude coefficients and first phase coefficients related to the codebook, and wherein, based on the parameter set for rank 3 and rank 4: the number (L) of second combining beams being equal to two, and the number of second bits amounts to two and is respectively related to second amplitude the number (L) of second combining beams being equal to two, and the number of second bits amounts to two and is respectively related to second amplitude coefficients and second phase coefficients related to the codebook. <EOS>