PURPOSE: To stably reproduce a received signal with high quality in the reception by the orthogonal modulation system by eliminating crosstalk due to phase distortion in a power amplifier stage or the like in a broadcast transmitter or the like in the orthogonal modulation system in which a carrier wave having an orthogonal relation to a video carrier wave is modulated by other information and the modulated signal is synthesized with the video carrier wave modulated by a video signal and the synthesized signal is transmitted.

CONSTITUTION: A detection control means 120 calculates a phase modulation component from a waveform of a video signal fetched by a waveform fetch means 119 and a waveform of an output signal of an orthogonal detection means 112 for the signal, a waveform processing means 121 applies waveform processing to the video signal according to the phase modulation component, a phase modulation means 122 applies phase-modulation to the carrier wave reproduced by the processed waveform and implements the orthogonal detection by using the carrier wave subjected to phase modulation.