This paper designs a single rotatable dual-polarized antenna polarimetric active radar calibrator (PARC) and proposes a corresponding dynamic calibration polarimetric (DPC) method. The novel PARC simplifies the system equipment and optimises the antenna's pattern. By modulating the time-delay of the retransmitted signal of the PARC, the polarimetric radar is calibrated with the DPC method. The simulations verify that the single dual-polarized antenna DPC scheme possesses better calibration accuracy than the double-antenna DPC scheme. (5 pages)