An RF unit receives radio-frequency signals where a plurality of channels
are frequency-multiplexed. An A-D unit converts the radio-frequency
signals to digital signals. A processing unit processes the plurality of
channels contained in the digital signals which have been converted by
the A-D unit. The processing unit includes: a band-pass filter, having
bands corresponding respectively to the plurality of
frequency-multiplexed channels, which separates the digital signals into
the plurality of channels; and a demodulation unit which demodulates the
plurality of channels separated by the band-pass filter.