On the Accuracy of the Envelope Method for the Measurement of Doppler Spread

The accuracy achievable by the envelope method in the measurement of the Doppler spread of a dispersive channel or, more generally, of any scintillating source that can be modeled as a Gaussian process is evaluated. Specifically, the effects of additive independent noise, finite sample size, and numerical differentiation are discussed, and analytical expressions are given for the resulting errors.