New methodology for plasma polarimeters calibration is suggested, based on the complex amplitude ratio (CAR) measurements. This methodology reduces calibration to determination of three complex parameters of transfer matrix, characterizing polarization changes in optical system. Having obtained transfer matrix, full characteristic of the optic system could be obtained: eigenstates, phase shift and relative attenuation of the slow and fast wave. Polarization state of the sounding electromagnetic wave after the plasma is determined from the measured complex amplitude ratio by simple inversion of transfer matrix. Calibration procedure under discussion is simpler, more transparent and reliable than traditional procedures, using Stokes vector technique or angular parameters of polarization ellipse. (C) 2013 Elsevier B.V. All rights reserved.