PURPOSE: To easily obtain good cross polarization discrimination by providing a power distributor, an amplifier, a variable phase shifter, a variable resistance attenuator, and a power synthesizer.

CONSTITUTION: A part of a signal outputted from the V polarization (vertical polarization) output terminal 8 or the H polarization (horizontal polarization) output terminal 9 of a group branching filter 5 is taken out by a distributor 2, and is amplified by a signal amplifier 25, and after the amplitude and the phase of it are adjusted by the variable phase shifter 4 and the variable resistance attenuator 3, it is synthesized with an H polarization output signal or a V polarization output signal from a group branch output terminal by the synthesizer 1. Accordingly, a cross polarization component in the signal can be canceled, and the good cross polarization discrimination can be obtained.