| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a digital broadcast receiving apparatus capable of receiving a modulation signal in which a carrier signal is suppressed such as a high definition television signal digitally modulated by the QAM (Quadrature Amplitude Modulation) or the like. <P>SOLUTION: The digital broadcast receiving apparatus adopts a double super-heterodyne system with first and second mixers 9, 13 as the basic building block. A first IF filter 11 employs a band pass filter with an in-band flatness and a low group delay deviation of a degree not deteriorating the demodulation characteristic as to the high definition television signal. A second IF filter adopts a SAW filter. The apparatus includes a third mixer 28 for applying frequency conversion to a second IF signal into a third IF signal, and the frequency of the converted third IF signal is selected to be lower than the frequency of the second IF signal. The apparatus includes a demodulator 33 for the high definition television signal to demodulate the high definition television signal included in the third IF signal. <P>COPYRIGHT: (C)2003,JPO |
