Patent ID: 8866558

Claim:
A voltage controlled oscillator (VCO) integrated with a semiconductor substrate, the VCO comprising: a pair of oscillator transistors each having a control terminal and an output terminal, wherein the oscillator transistors are cross-coupled to each other such that an output of each oscillator transistor is coupled to an input of the other oscillator transistor; and a resonant circuit connected between the control terminals of the pair of oscillator transistors, wherein the resonant circuit comprises: first and second varactors each having a first end thereof connected to a tuning voltage input and having a second end connected to the control terminal of a corresponding one of the oscillator transistors, and a dual-mode coplanar waveguide resonator, comprising: an electrically conductive common line extending lengthwise in a first direction and connected to a first supply voltage for the oscillator transistors; and at least first through fifth electrically conductive lines sequentially arranged lengthwise substantially in parallel with each other in a second direction which is substantially perpendicular to the electrically conductive common line, each of the first through fifth linear electrically conductive lines having a first end and a second end opposite the first end, wherein the electrically conductive common line and the first through fifth linear electrically conductive lines are all arranged at a first level with respect to the semiconductor substrate, wherein the first ends of the first through fifth electrically conductive lines are all connected to the electrically conductive common line, wherein the second ends of the second and fourth electrically conductive lines are each connected to the output terminal of a corresponding one of the oscillator transistors, and wherein the second ends of the first, third, and fifth electrically conductive lines are floating; wherein a length of each of the second and fourth electrically conductive lines is substantially less than ¼ of a wavelength at any oscillating frequency of the VCO.