| 摘要 |
<P>PROBLEM TO BE SOLVED: To compensate the phase difference between orthogonal components occurring at analog circuits at transmission and reception sides. <P>SOLUTION: The orthogonal components are detected by an orthogonal demodulator 2 and the output S1 is converted to a digital signal S2 by an A/D converter 3. The frequency and phase offset are corrected by a phase rotation signal ON in a complex multiplier 5 for deriving demodulation output S5. An error signal E and a polarity signal D are generated for each component detected from the signal S5 by a determining device 7. Based on the signals E, D, the phase rotation signal ON and the antiphase signal ON' are generated by PD8, LPF9, NCO10. In the demodulator where the frequency and phase offset are corrected by the complex multiplier 5 based on the phase rotation signal ON, a phase compensator 4 is provided where the phase of the output of the signal S2 is compensated based on the correlation between the polarity signal of the signal S2 and a signal after the phase rotation based on the phase rotation signal ON' of the error signal E, and the occurrence of the phase difference is corrected between the orthogonal components at the orthogonal demodulator 2 and the analog section of the A/D conversion section 3. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
