| 摘要 |
PURPOSE:To perform the recovery of a carrier under a state where a hardware is simplified remarkably by mapping phase information on a memory corresponding to the spatial arrangement of a signal point, and extracting the phase information when a local oscillation frequency is deviated from a carrier frequency from the memory. CONSTITUTION:When deviation exists between the frequency of a carrier signal and that of the output signal of a voltage controlled oscillator 24, it is orthogonally detected at an orthogonal detection circuit 10. And the address area of the memory 32 accessed by a digital in-phase component value and a digital orthogonal component value outputted from analog-digital conversion circuits 30I and 30Q becomes the address area corresponding to either the half area of the spatial arrangement of the signal point from a synchronous incoming signal corresponding to a difference. Thus, the phase information read out from the area, that is, the phase information to eliminate the deviation is supplied to an oscillation controlled voltage generation circuit 50. In such a way, the oscillation controlled voltage of the circuit 50 is moved in a direction to reduce the deviation, and finally, the oscillation frequency becomes the carrier frequency. |
