A method for acquiring channel information, comprising: mapping (101, 301), by a base station, first preset antennas in an antenna array to pilot signals, wherein the mapping comprises associating each of the first preset antennas to a physical resource unit and mapping information about each of the first preset antennas to the corresponding physical resource unit, and wherein the physical resource units carry the pilot signals; sending (102, 302), by the base station, the pilot signals and antenna configuration information to a terminal, wherein the antenna configuration information comprises pattern information of the first preset antennas and pattern information of second preset antennas; and receiving (103, 308), by the base station, channel state information of the second preset antennas that is fed back by the terminal; wherein the first preset antennas and the second preset antennas are in the same antenna array, and the first preset antennas are different from the second preset antennas characterized in that the channel state information of the second preset antennas, that is fed back by the terminal, is determined by: acquiring, by the terminal, a channel matrix corresponding to the first preset antennas from the pilot signals; acquiring, by the terminal, a position relationship between the first preset antennas and the second preset antennas from the antenna configuration information; and performing, by the terminal, an interpolation operation according to the channel matrix corresponding to the first preset antennas and the position relationship between the first preset antennas and the second preset antennas, to obtain the channel state information of the second preset antennas. mapping (101, 301), by a base station, first preset antennas in an antenna array to pilot signals, wherein the mapping comprises associating each of the first preset antennas to a physical resource unit and mapping information about each of the first preset antennas to the corresponding physical resource unit, and wherein the physical resource units carry the pilot signals; sending (102, 302), by the base station, the pilot signals and antenna configuration information to a terminal, wherein the antenna configuration information comprises pattern information of the first preset antennas and pattern information of second preset antennas; and receiving (103, 308), by the base station, channel state information of the second preset antennas that is fed back by the terminal; wherein the first preset antennas and the second preset antennas are in the same antenna array, and the first preset antennas are different from the second preset antennas characterized in that the channel state information of the second preset antennas, that is fed back by the terminal, is determined by: acquiring, by the terminal, a channel matrix corresponding to the first preset antennas from the pilot signals; acquiring, by the terminal, a position relationship between the first preset antennas and the second preset antennas from the antenna configuration information; and performing, by the terminal, an interpolation operation according to the channel matrix corresponding to the first preset antennas and the position relationship between the first preset antennas and the second preset antennas, to obtain the channel state information of the second preset antennas. acquiring, by the terminal, a channel matrix corresponding to the first preset antennas from the pilot signals; acquiring, by the terminal, a position relationship between the first preset antennas and the second preset antennas from the antenna configuration information; and performing, by the terminal, an interpolation operation according to the channel matrix corresponding to the first preset antennas and the position relationship between the first preset antennas and the second preset antennas, to obtain the channel state information of the second preset antennas.