These limitations have been overcome by the use of mm-wave oscillators and VCOs in a lumped-element circuit form in which a temperature compensating capacitor is located directly at the circuit elements (Gunn and/or varactor diode) to be compensated.
A schematic drawing and circuit layout of a temperature compensated Ka-band (26 to 40 GHz) VCO with two possible placements of a compensating capacitor [C.
A material parameter of primary interest for a compensating capacitor is the temperature coefficient of the capacitor's dielectric material.
Materials for a compensating capacitor for a lumped-element or printed-circuit mm-wave VCO or oscillator are shown in Table 1.
The compensating capacitor was fabricated from 10 mil thick copper clad Epsilom-10 ([Epsilon.
A lumped-element compensating capacitor fabricated from 5 mil thick metalized Kapton was used in parallel with the Gunn diode package.