spectral width

A measure of the spread of the Doppler spectrum and consequently is sensitive to the spread in the particle size spectra. A larger spectral width is indicative of the presence of a broader range of sizes of hydrometeors.

The wavelength interval over which the magnitude of all spectral components is equal to or greater than a specified fraction of the magnitude of the component having the maximum value. Note 1: In optical communications applications, the usual method of specifying spectral width is the full width at half maximum. This method may be difficult to apply when the spectrum has a complex shape. Another method of specifying spectral width is a special case of root-mean-square deviation where the independent variable is wavelength, λ, and f (λ) is a suitable radiometric quantity. Note 2: The relative spectral width, λ/λ, is frequently used where λ is obtained according to note 1, and λ is the center wavelength.