| 摘要 |
PURPOSE:To stabilize the oscillation frequency of a voltage controlled oscillator(VCO) by constituting the phase comparator(PC) of a first and a second multipliers, a first and a second phase shifters, and a subtractor. CONSTITUTION:A phase comparator(PC) 1 is constituted of a first and a second pi/2 phase shifters 4, 5, a first and a second multipliers 6, 7, and a subtractor 8. In this state, in the PC 1, an input signal, and the output signal of a voltage control oscillator(VCO) 3 are bisected respectively and thereafter, by bringing one signal of each of them to pi/2 phase shift and subtracting the multiplication signal of the output signal of the VCO 3 brought to pi/2 and the input signal which is not brought to phase shift from the multiplication signal of the input signal brought to pi/2 phase shift and the output signal of the VCO 3 which is not brought to phase shift, a phase error signal is obtained. In such a manner, the stability of an oscillation frequency of the VCO 3 is not deteriorated. |
