A novel in-situ impedance probing method for multistage power amplifier analysis and design

A novel in-situ impedance probing method is described which provides a noninvasive means to determine in-situ impedances and nodal mismatch, compute precise gain budgets, assess stability, and compute active external and intrinsic device load lines within a multistage power amplifier, using a single linear simulation. Precise determination of important performance parameters and figures of merit can be efficiently calculated and used for design. The method can also be generally applied to any chain of networks which comprise a circuit. A 10W high voltage S-Band power amplifier was successfully designed, using this technique, to demonstrate its effectiveness.