Voltage controlled oscillator with enhanced sensitivity of change of oscillation frequency

Abstract

A voltage controlled oscillator comprises an oscillation transistor, a varactor diode, a resonance circuit which is coupled to the oscillation transistor, and a switching diode which changes over a resonance frequency of the resonance circuit, wherein the resonance circuit includes a first strip conductor which is served for grounding a cathode of the varactor diode in terms of direct current and a second strip conductor which is served for coupling a cathode of the varactor diode with the oscillation transistor, the switching diode is connected to the first strip conductor in parallel in terms of high frequency and has a cathode thereof grounded, and a control voltage which is served for changing a capacitive value of the varactor diode is applied to a connection point between the cathode of the varactor diode and the second strip conductor through a choke inductor.

Dependencies are inferred from the claim text.