| 摘要 |
PROBLEM TO BE SOLVED: To provide improved demodulation characteristics by detecting the presence/absence of delay waves generated in a transmission line by observing the output of a correlation device for clock reproduction and selectively using a delay detector and an equalizer by the detected result. SOLUTION: A sampling processing part 1 samples reception signals y (t) from the transmission line and outputs a sample value sequence yn to an input butter 2. A delay amount estimation part 3 receives the sample value sequence outputted from the input butter 2, estimates a delay amount in the transmission line and outputs it to a selection control part 5. When the estimated delay amount is equal to or less than a changeover threshold value, the selection control part 5 selects the use of the delay detector 6 and the delay detector 6 obtains an estimated transmission symbol from the sample value sequence yn. On the other hand, when the estimated delay amount is larger than the changeover threshold value, the selection control part 5 selects the use of the equalizer 7 and the equalizer 7 obtains the estimation transmission symbol from the sample value sequence yn outputted from the input buffer 2. |
