| 摘要 |
PURPOSE:To make a drawing-in range broad while making convergence possible even in greater initial interference between codes, by comparing a demodulated waveform value of two series of a received polyphase and multivalue modulation with a prescribed value, and changing the characteristic of an equalizer through the discrimination of polyphase only when it is greater than the rescribed value. CONSTITUTION:The demodulated waveform of two series of polyphase and multivalue modulation is outputted with 2 series of signals by an input to an equalizer 3 from terminals 1, 2, and the output is branched into three and it is inputted to an evaluating value calculation circuit 4 and the evaluating value is inputted to a comparison circuit 8. where it is compared with a prescribed value inputted from a terminal 7, and when the input from a circuit 4 is greater, 1 is outputted to a discriminating circuit 5 and, when smaller, 0 is outputted. Further, only when the circuit 5 inputs 1, it decides that the received waveform is distributed in the range where the decision of the polyphase modulation is made accurate. The output is inputted to a correction circuit 6 according to the output of the equalizer 3. Next, the circuit 6 outputs a signal to change the characteristic of the equalizer 3, allowing to make adaptive the equalization of wider drawing-n range. |
