Patent ID: 8248172

Claim:
A wideband oscillation circuit comprising: an oscillator that outputs an oscillation signal; a filter that receives and filters the oscillation signal output from the oscillator and outputs an injection locked signal; and an injection locked frequency divider that performs a free-run operation and outputs a divided signal of the oscillation signal while the oscillating operation thereof is being controlled by the injection locked signal, the division ratio of which varies in accordance with a control signal, wherein: the injection locked frequency divider is a ring oscillator type having a differential two-stage configuration, the filter controls the passing characteristic that causes the oscillation signal to pass with respect to time in accordance with a filter control signal locked with the divided signal to generate the injection locked signal, and the filter control signal uses an output signal in one of the stages of the ring oscillator type injection locked frequency divider to connect an output in the other stage of the ring oscillator type injection locked frequency divider in accordance with the injection locked signal.