Satellite broadcasting receiving tuner which inhibits interference caused by satellite broadcast signals having one octave higher frequency band

A satellite broadcasting receiving tuner comprising:

• first and second demodulators to which satellite broadcasting signals of a plurality of channels arranged within a frequency band higher than 1 octave are inputted;
• and
• a local oscillator which oscillates at the same frequency of the frequency of a desired reception satellite broadcasting signal in said satellite broadcasting signals;
• wherein a phase of a local oscillation signal inputted from said local oscillator to said first demodulator and a phase of a local oscillation signal inputted from said local oscillator to said second demodulator are made different from each other by 90 degrees, and said first and second demodulators output baseband signals, respectively;
• said first demodulator comprising a fundamental wave mixer for generating a mixed wave of a fundamental wave of the local oscillation signal from said local oscillator and said satellite broadcasting signal;
• said second demodulator comprising a fundamental wave mixer for generating a mixed wave of the fundamental wave of the local oscillation signal from said local oscillator and said satellite broadcasting signal;
• a higher harmonic wave attenuator for passing the fundamental wave of the local oscillation signal from said local oscillator therethrough and for attenuating higher harmonic waves is disposed between said local oscillator and said first and second demodulator;
• and
• a local oscillation signal having the same frequency of the frequency of the desired reception satellite broadcasting signal is inputted into said first and second demodulators via said higher harmonic wave attenuator.