In this paper, we briefly introduce the LINC amplifier, and discuss its mismatch issues that reduce its linearity and degrade its performance. A calibration approach for the LINC amplifier is proposed for multi-carrier system applications such as OFDM systems. The technique estimates the LINC amplifier calibration coefficient from the LINC amplifier output signal envelope by using a min-minimum criterion. Computer simulations are carried out to validate the proposed LINC amplifier calibration approach. It is demonstrated that the calibration coefficient can be accurately determined, and the mismatch compensated, by the proposed approach, so that the LINC amplifier performance can be significantly improved.