Abstract :
Circuit equations of the abrupt junction varactor doubler have been consolidated into one implicit equation in one unknown. For tuned input and output circuits, this equation reduces to a cubic equation that is solved explicitly as a function of available input power and circuit loading. Optimum loading conditions for maximum power output are functions of only a single composite parameter. For general terminating impedances at input and output frequencies, the consolidated equation is readily solved numerically using the tuned results as a starting point. As examples, doubler frequency responses, with single-and double-tuned load circuits, have been calculated. Surprisingly, double tuning is of Iimited value in enhancing the instantaneous bandwidth. In addition, for single-tuned load circuits, the frequency response as a function of bias voltage has been calculated, showing the potentiality of greater than 20-percent frequency tunability.
