Patent ID: 8324977

Claim:
An oscillator circuit comprising: a voltage controlled oscillator (VCO) core having an output terminal for providing an oscillatory output signal thereat and having a supply terminal for receiving a supply voltage from a voltage supply; a subsequent circuit coupled to the output terminal of the VCO core and having a supply terminal for receiving a supply voltage from the voltage supply; and a decoupling member arranged between the supply terminal of the VCO core and the supply terminal of the subsequent circuit for preventing high-frequency signals generated by the subsequent circuit at its supply terminal from entering the VCO core, wherein the decoupling member comprises a transmission line having a first terminal and a second terminal, a diode having a first terminal coupled to the second terminal of the transmission line and a second terminal coupled to the supply terminal of the VCO core, and a capacitor having a first terminal coupled to the first terminal of the transmission line, and a second terminal coupled to the second terminal of the transmission line; wherein the transmission line has a length of which is substantially one quarter of a wavelength associated with a second harmonic oscillation.