| 摘要 |
PURPOSE:To reduce mean computing quantity as keeping performance and to attain low power consumption by providing a waveform distortion detector, an equalization selector which selects whether a selector should be used at every burst based on the detection of the detector, and an equalizer which compensates waveform distortion due to a delay wave at need. CONSTITUTION:The impulse response h(n) of a reception signal inputted to a distortion detector 14 on a line including the feature of a transmission/ reception filter can be estimated by taking cross-correlation with a reference signal 13 by the detector 14. It is converted to frequency characteristic by taking the sum of h (n) xexp (-jomegaX time difference between a first component and an n-th component, omega= angular frequency). Thereby, a notch is generated when fading with frequency selectivity occurs, however, distortion is compensated by selecting the equalizer 16 by assuming that the fading exists only when such value exceeds a threshold value. When no fading occurs, demodulation is performed by a demodulator 12 of common usage, and the mean computing quantity can be reduced, and the low power consumption can be attained. |
