| 摘要 |
A radio data communication terminal that includes a phase rotator for correcting a narrow-band modulation system, an equalizer for correcting a transmission path distortion of the frame signal corrected in phase, and a calculating circuit for calculating the phase error by using a preamble in the frame signal, he phase error is used for the phase error correction in the phase rotating means. The terminal further includes a transmission path distortion estimator for estimating the transmission path distortion by using the preamble in the frame signal corrected in phase and calculating tap coefficients necessary for the equalizer. A setter is provided for setting the tap coefficients to the equalizer and a first delay circuit delays the frame signal. A selection circuit selects an input or output of the first delay circuit and outputs the selected one to the phase rotator so that the calculating circuit and the transmission path distortion estimator operate while using the same portion of the preamble. |
