<p>A signal processing section 3 is set up which provides an anti-phase component signal S extracted by an anti-phase component extracting section 2 with a transfer characteristic (H d + H x ) / (H d - H x ); an adder 4 adds the phase-inverted signal of the anti-phase component signal S provided with the transfer characteristic by the signal processing section 3 and an in-phase component signal M extracted by an in-phase component extracting section 1; and an adder 5 adds the anti-phase component signal S provided with the transfer characteristic by the signal processing section 3 and the in-phase component signal M extracted by the in-phase component extracting section 1.</p>