| 摘要 |
PURPOSE:To secure the quick phase syhchronous lead-in of the regenerated carrier wave by giving the second partial response conversion to the demodulated output of the orthogonal partial response modulated wave and then comparing the converted demodulated output with the phase detection output. CONSTITUTION:The orthogonal partial response modulated wave applied to input terminal IN is sent to demodulator circuit DEM and carrier wave regenerator CRC, and the demodulated output given from circuit DEM is drawn out of output terminal OUT1 and OUT2. In this case, either one or both of these demodulated output is/ are applied to decision circuit DET to be given the second partial response conversion, and the this converted signal is compared with the detection output signal. After this, if a coincidence is obtained through the above comparison, it is decided that the regenerated carrier wave is led into the desirable phase. In case no coincidence is obtained, the lead-in phase of carvier wave regenerator CRC is shifted by 45 deg. or the second lead-in action is given. |
