Proposed is a new scheme of frequency-domain dynamic polarimetric calibration by designing a polarimetric active radar calibrator (PARC) with two rotatable antennas. The proposed scheme can eliminate clutter and the error due to a set of measurements in the traditional static calibration scheme. The calibration results in the proposed scheme are not affected by the initial angles of the PARC antennas. The calibration accuracy of the proposed method is better than the static calibration methods, for example, the target spinor calibration and the full polarimetric calibration technique. This result was verified by simulations under various conditions.