| 摘要 |
PROBLEM TO BE SOLVED: To stabilize distortion compensation and to improve the throughput of transmitting data controlling the phase of a demodulation signal to be a prescribed value to stabilize the operation of a loop from an initial stage and performing step following control through the use of the preamble of transmitting data so as to simplify the circuit constitution. SOLUTION: A detecting window is set to the preamble position of transmitting data to detect the phase difference of the demodulation signal 131I with respect to a common-mode signal 101 within the time when the window is opened. When the phase difference is within the prescribed value, a threshold value detecting part 31 judges effectiveness and supplies a phase control signal to a RAM part 32 for each transmission data slot. A RAM part 32 sets an offset value from a control part 34 to be a phase difference signal 141I to output to a phase controller 18 and sets the phase of the signal 131I from an orthogonal demodulator 16 to be a phase control cycle to repeat step control for each transmission slot until becoming smaller than a minimum phase difference. A loop is always kept to be closed to execute Cartesian loop linearizer control. |
