ABSTRACT
The way nonlinear effects are modeled and characterized depends on the properties of the input signal. Signals having frequency components above a few hundred megahertz are generally regarded as radio frequency (RF) or microwave signals. The signals to be characterized in RF and microwave circuits are either correlated, in the case of communication and radar systems, or uncorrelated noise in the case of many imaging systems. Frequency domain characterization of RF and microwave circuits directly provides the types of performance parameters required in communication systems as well as many other applications of RF and microwave circuits. The development of the associated discrete model (ADM) of an element begins with a time discretization of the constitutive relation of the element. The final circuit combining the ADM of all of the elements is linear with resistors and current sources, as well as a few special elements such as voltage sources.
