PURPOSE: To minimize interference of polarized waves between received radio waves from each satellite by fixing an arm supporting a parabolic reflecting mirror at a turned angle at which a mean value of deviations in polarized planes between plural satellites at an installed district is minimized.

CONSTITUTION: A parabolic reflecting mirror 4 is adjusted roughly in the direction of a center C of CS satellites S1-S4 so that received radio waves from the satellites S1-S4 have almost the same electric field strength. This is confirmed by obtaining an optimum value through the turning of a turning arm 1 so that leakage of a received radio wave from, e.g. the satellite S3 is minimized through a different polarized wave to the satellite S2. Furthermore, the turning arm 1 is adjusted again to obtain a balance of the mean values of both the adjustment procedures and to set a turning angle so that the leakage of a received radio wave from the satellite S2 is minimized through a different polarized wave to the satellite S3. The adjustment above is implemented by turning the turning arm 1 so that a difference 31° of the polarized planes for each antenna installed district throughout Japan is eliminated.