The influence of transistor nonlinearities on intrinsic noise

Transistor nonlinearities are examined to assess their effects on intrinsic noise properties. The noise sources in a nonlinear equivalent-circuit model are determined using low frequency spectrum analyzer and microwave noise figure meter data, while the other circuit elements are determined using bias-dependent scattering parameter measurements and analytic nonlinear parameter expressions. This model identifies the intrinsic noise mechanisms, and allows the investigation of their influence on extrinsic noise when the device is operated in either linear of the nonlinear regime. Using the example of AlGaN/GaN high electron mobility transistor, the model correctly predicts the near-carrier sideband amplitude and phase noise simultaneously.