| 摘要 |
<p>The invention provides an OFDM synchronization demodulation circuit which includes a receiving circuit for receiving an orthogonal modulated wave of an orthogonal frequency division multiplex (OFDM) modulated signal having an available symbol period and a guard period in waveform which coincides with a part of the available symbol period, an orthogonal axes demodulation circuit for demodulating an in-phase axis detection signal and an orthogonal axis detection signal through orthogonal detection for the OFDM modulated wave from the receiving circuit, a first delay circuit for delaying the in-phase axis detection signal by the available symbol period, a second delay circuit for delaying the orthogonal axis detection signal by the available symbol period, a correlation calculation circuit for calculating coefficients of the correlations of the in-phase axis detection signal and the orthogonal axis detection signal from the orthogonal demodulation circuit with the output of the first or the second delay circuits, a guard timing detection circuit for detecting a timing of the guard period in the demodulation outputs from the orthogonal demodulation circuit, and an OFDM signal demodulation circuit for demodulating the OFDM modulated signal by extracting the available symbol period signal only from the demodulated output of the orthogonal demodulation circuit using the timing signal. <IMAGE></p> |
