A method and apparatus for calibrating an antenna array. The apparatus includes first and second couplers, a calibration transceiver, and a controller. The first coupler operably is connected to a first number of antennas. The second coupler is operably connected to a second number of antennas. The calibration transceiver is operably connected to the first and second couplers via a common path. The controller is configured to perform calibration on at least one or more transmit/receive paths for the second number of antennas based on at least one or more signals received from or transmitted to the first and second couplers via the common path by the calibration transceiver. The first and second numbers of antennas may each include only one antenna, or the first and second numbers of antennas may each be a group of multiple antennas.