A method of transmitting a signal using beamforming by a base station in a wireless communication system, the method comprising: determining to disable beam superposition based on a first trigger condition that a standard deviation of a first receive signal strength indicator, RSSI, or a first carrier to interference and noise ratio, CINR, for a combination of two or more beams reported by a mobile station exceeds a beam superposition release threshold, wherein the beam superposition release threshold indicates a threshold for a maximum standard deviation of a second RSSI or a second CINR for an individual superposed beam: selecting one or more beams from among a plurality of unitary beams corresponding to an array antenna of the base station based on information about a third RSSI or a third CINR measured by the mobile station for each of the one or more beams; performing a communication with the mobile station through the one or more beams; determining to enable the beam superposition based on a second trigger condition that a standard deviation of a fourth RSSI or a fourth CINR for the one or more beams reported by the mobile station exceeds a beam superposition allocation threshold, wherein the beam superposition allocation threshold indicates a threshold for a maximum standard deviation of a fifth RSSI or a fifth CINR for an individual unitary beam: determining a number of unitary beams to be superposed and selecting at least two beams to be superposed from among the plurality of unitary beams based on information about a sixth RSSI or a sixth CINR measured by the mobile station for a combination of the at least two beams; configuring the array antenna of the base station to form a superposed beam by superposing the at least two beams; and performing a communication with the mobile station through the superposed beam; wherein a maximum number of the at least two beams to be superposed is limited to a number of radio frequency, RF, paths of the base station. determining to disable beam superposition based on a first trigger condition that a standard deviation of a first receive signal strength indicator, RSSI, or a first carrier to interference and noise ratio, CINR, for a combination of two or more beams reported by a mobile station exceeds a beam superposition release threshold, wherein the beam superposition release threshold indicates a threshold for a maximum standard deviation of a second RSSI or a second CINR for an individual superposed beam: selecting one or more beams from among a plurality of unitary beams corresponding to an array antenna of the base station based on information about a third RSSI or a third CINR measured by the mobile station for each of the one or more beams; performing a communication with the mobile station through the one or more beams; selecting one or more beams from among a plurality of unitary beams corresponding to an array antenna of the base station based on information about a third RSSI or a third CINR measured by the mobile station for each of the one or more beams; performing a communication with the mobile station through the one or more beams; determining to enable the beam superposition based on a second trigger condition that a standard deviation of a fourth RSSI or a fourth CINR for the one or more beams reported by the mobile station exceeds a beam superposition allocation threshold, wherein the beam superposition allocation threshold indicates a threshold for a maximum standard deviation of a fifth RSSI or a fifth CINR for an individual unitary beam: determining a number of unitary beams to be superposed and selecting at least two beams to be superposed from among the plurality of unitary beams based on information about a sixth RSSI or a sixth CINR measured by the mobile station for a combination of the at least two beams; configuring the array antenna of the base station to form a superposed beam by superposing the at least two beams; and performing a communication with the mobile station through the superposed beam; determining a number of unitary beams to be superposed and selecting at least two beams to be superposed from among the plurality of unitary beams based on information about a sixth RSSI or a sixth CINR measured by the mobile station for a combination of the at least two beams; configuring the array antenna of the base station to form a superposed beam by superposing the at least two beams; and performing a communication with the mobile station through the superposed beam; wherein a maximum number of the at least two beams to be superposed is limited to a number of radio frequency, RF, paths of the base station.