To secure high C/N and stability in frequency, to suppress a leakage of an unnecessary signal outside a band even when a frequency variable width gets wider and to achieve impedance matching at the same time.
A voltage controlled oscillator includes: a voltage controlled oscillation circuit 1, an oscillation frequency thereof being controlled by a control voltage signal; a PLL circuit 2 that generates a control voltage signal to be input to the voltage controlled oscillation circuit 1; a multiplier circuit 3 that multiplies an oscillation signal output from the voltage controlled oscillation circuit 1; and a band-pass filter and trap circuit 4 that sets a pass band for passing a signal with a predetermined multiplication number of multiplication signals output from the multiplier circuit 3 and a trap frequency to trap a frequency equal to the frequency of the oscillation signal input to the multiplier circuit 3. The control voltage signal is branched and input to an inter-stage coupling and trap circuit 15 to vary the pass band and the trap frequency of the inter-stage coupling and trap circuit 15 in synchronization with the control voltage signal, and also to adjust inter-stage coupling.
| WO/2008/148535 | TIME-TO-AMPLITUDE CONVERTER COMPONENT |
| JPH05243982 | METHOD AND DEVICE FOR SYNCHRONIZING SIGNAL |
| JP3744780 | Oscillator circuit |
| JPH06164445A | 1994-06-10 | |||
| JP2004343253A | 2004-12-02 | |||
| JPH09232915A | 1997-09-05 | |||
| JP2001274629A | 2001-10-05 | |||
| JP2004096470A | 2004-03-25 | |||
| JPH06326606A | 1994-11-25 |
Amada Masayuki
Yoshimasa Okada