| 摘要 |
PROBLEM TO BE SOLVED: To automatically remote the quadrature error of a quadrature demodulator. SOLUTION: An orthogonal error detector 17 estimates the orthogonal error just before a phase rotation while using error signals Ei and Eq outputted by an error detector 14, polarity signals Di and Dq and a phase signal Ang outputted by an NCO. A quadrature controller 15 estimates an error signal before the phase rotation from the error signals Ei and Eq after the phase rotation due to a complex multiplier 8 by performing complex multiplication to an orthogonal error signal Qd outputted by the orthogonal error detector 17. Since the quadrature controller 15 is located before the phase rotation, the orthogonal error is removed by this estimated error signal. |
