Expanding definitions of gain by taking harmonic content into account

We expand the definitions of power gain, transducer gain, and available gain by taking harmonic content into account. Furthermore, we show that under special conditions, these expanded definitions of gain can be expressed in terms of nonlinear large-signal scattering parameters. Finally, we provide an example showing how these expanded forms of gain and nonlinear large-signal scattering parameters can provide us with valuable information regarding the behavior of nonlinear models.