| 摘要 |
PURPOSE:To deliver the signal having good carrier wave reproducing characteristics with a simple constitution of circuit without using any complicated circuit, by using a phase modulator which is capable of the modulation of phase with a code signal of a low level. CONSTITUTION:A modulating part includes an Esaki diode pair circuit 3 using the outputs of an LPF2 and a phase shifter 8 for the input and a BPF4. The circuit 3 contains a transformer T for phase inversion of carrier wave, carrier wave driving resistors R1-R4, a code signal driving resistor R5, a load resistor R6 for output plus Esaki diodes ED1 and ED2. The code signal is applied to a common joint of the diodes ED1 and ED2 via a BPF4, and the carrier wave of adverse phase is applied across these diodes each. Thus the positive or negative pulse signal is delivered from the common joint. This signal is turned into another signal which is obtained by the phase deviated modulation carried out through the BPF4 to be applied to a phase wave detector 5 that uses the received signal G for the input. Then a VCO7 is controlled via a loop filter 6 to deliver the reproduced signal Q. |
