| 摘要 |
PURPOSE:To obtain a proper demodulated signal by controlling a received modulated wave signal by a regenerative carrier signal outputted from a voltage controlled oscillator, and controlling the regenerative carrier signal by a carrier control signal outputted from a carrier control signal generation circuit. CONSTITUTION:P and Q channel data PD, QD are turned into absolute values by a first and a second absolute valuing means 10,11, and are outputted as P and Q absolute valued data PD1, PD2 to a first and a second arithmetic means 30,31, and simultaneously, they are supplied to a signal point discriminating means 12, and are outputted as the demodulated signal S6. Providing the data PD1, QD1 are P, Q respectively, the arithmetic means 30, 31 execute the arithmetic operation of Q+Q/4-P/2 and P+P/4-Q/2 respectively. One of arithmetic result data PD1a, QD1a supplied to a signal processing means 32 is selected in accordance with a phase area shown in the demodulated signal S6, and simultaneously, is turned inversely or normal, and is outputted as the carrier control signal S5a. |
