| 摘要 |
An oscillation circuit including first and second voltage-controlled oscillators (VC01, VC02) each having a resonance circuit including a pair of varactor diodes (61, 62, 71, 72), and first and second buffer amplifiers (BAMP1, BAMP2) for feeding-back high frequency signals generated from the first and second voltage-controlled oscillators (VC01, VC02) to the second and first voltage-controlled oscillators (VC02, VC01), respectively. A control voltage (Vc) is applied to the varactor diodes (61, 62, 71, 72) to generate output high frequency signals having a same frequency and a mutual phase difference of 90 degrees from the first and second voltage-controlled oscillators (VC01, VC02). By adjusting an amplitude of the control voltage (Vc), resonant points of the resonance circuits of the first and second voltage-controlled oscillators (VC01, VC02) are changed and the frequency of the output high frequency signals is changed, while phase noise can be sufficiently suppressed over a wide frequency range and a power consumption can be lowered. <IMAGE> |
