Patent ID: 7940858

Claim:
An apparatus for calibration of a transmitter having a plurality of antennas, comprising: a modulation unit for modulating a downlink signal to calculate a reference signal; a digital Intermediate Frequency (IF) unit for converting the reference signal to an IF signal; an up-converting unit for converting the IF signal to a Radio Frequency (RF) signal; a down-converter for generating a received signal for each of a plurality of paths from the RF signal to be transmitted through each path, the plurality of paths respectively corresponding to the plurality of antennas; and a calibrator for calculating a correction value for each path and a delay value for each path by using the reference signal and the received signal for each path, wherein the digital IF unit uses the delay value for each path and the correction value for each path to calibrate a path delay between the paths of a next downlink signal and a phase characteristic between the paths of the next downlink signal.