The Spectrum Mode can be enabled if the setup includes a Spectrum Analyzer when using a scalar setup or a PNA-X with option S93090 when using a vectorial setup.
The Spectrum mode consists of measuring the spectrum traces for each power step. It can be useful if the need is to see the evolution of the DUT output signal spectrum in the function of the input power.
Multiple options are available to set the spectrum analyzer or the VNA and optimize the measurement speed and accuracy.