To measure the area under the curve in a power spectral analysis of dBvolts versus frequency, one can utilize the width at half height (FWHM) of the spectral peak. By representing the peak with a functional form such as Gaussian or Lorentzian, the relationship between FWHM and the area can be derived through analytical or semi-numerical methods. This approach assumes that the curve's shape is determined solely by the FWHM parameter. However, accuracy may be limited unless the spectrum closely aligns with the chosen analytical model. A more straightforward method is to numerically integrate the actual spectrum for precise results.
