New Design Approach for Wide-Band FET Voltage-Controlled Oscillators

A new, computer-assisted method, based on small-signal "S" parameters, is described for the systematic design of wide-band VCO's. The method has been applied to design 6-12-GHz and 12-18-GHz GaAs FET VCO's, and it has shown an excellent capability to predict the maximum obtainable tuning bandwidth. The tuning linearity of the VCO's has also been optimized Delta f/f <= +-0.4 percent over a 3-GHz bandwidth.