Abstract: A method for calibrating an antenna system (1) including a antenna elements (3) connected to signal receiver units (4) at an RF signal input port thereof comprising, generating an RF calibration signal (62), applying the RF calibration signal to the RF signal input port of the signal receiver units without applying the calibration signal via the antenna elements (3). The response of the antenna system to the calibration signal is measured, and a signal correction is calculated according to the measured response. The signal correction is applied to the response of the antenna system to signals subsequently received at the signal receiver units via the antenna elements of the antenna system.