| 摘要 |
<p>An orthogonal amplitude demodulator (200) demodulates a modulated signal R which has been subjected to an orthogonal amplitude modulation. Oscillators (40i, 40q) generate an in-phase carrier signal RecSin having a rectangular waveform, a trapezoid waveform, or a waveform similar to them and an orthogonal carrier signal RecCos having a phase shifted by 1/4 cycle as compared to the in-phase carrier signal RecSin. A first and a second mixer (42i, 42q) mix the modulated signal R with the in-phase carrier signal RecSin and the orthogonal carrier signal RecCos. A first and a second integrator (44i, 44q) integrate the output signals (RI, RQ) of the first and the second mixers (42i, 42q) during a period corresponding to the cycle of the in-phase carrier signal and the orthogonal carrier signal. The first and the second A/D converter (48i, 48q) convert outputs of the first and the second integrator (44i, 44q) into digital values, respectively.</p> |
