Active and passive broadbanding of parametric amplifiers

A new theory for broadbanding single-tuned parametric amplifiers using both active and passive networks is discussed. The design criteria for broadbanding networks are evaluated from algebraic analysis, computer synthesis and experiment, and are found to be significantly different from those derived from previous analyses. Amplifier bandwidths for various types of broadbanding are calculated, and it is seen that, for amplifiers using typical varactor diodes, the bandwidth of an actively broadbanded amplifier (with a flat gain response) can be as much as 1.6 times that of a passively broadbanded amplifer. In addition, active broadbanding is found to offer a number of practical advantages, including increased gain stability.