X-parameters: The New Paradigm For Measurement, Modeling, And Design Of Nonlinear Rf And Microwave Components

摘要

For more than 40 years, S-parameters, or scattering parameters, have been among the most important of all the foundations of microwave theory and techniques.rnS-parameters are easy to measure at high frequencies with a vector network analyzer (VNA). A well-calibrated S-parameter measurement represents intrinsic properties of the DUT, independent of the VNA system used to characterize it. These DUT properties (gain, loss, reflection coefficient, etc.) are familiar, intuitive, and important. S-parameters are still commonly used for nonlinear devices such as transistors and amplifiers. The problem, often forgotten or taken for granted, is that S-parameters only describe properly the behavior of a nonlinear component in response to small signal stimuli for which the device can be approximated as a linear component at a fixed DC, or static, operating point.