Practical applications of nonlinear measurements

We contrast linear, VNA-based measurements, involving ratios of the magnitude and phase of individual frequency components, to measurements of nonlinear devices and circuits, where the relative phase between frequency components and the actual impedance in which a device is embedded are important. The architectures and calibration techniques for several types of instruments designed to satisfy these requirements are presented and compared. Examples of the use of these instruments for measurement and model development of nonlinear circuits are presented.