JPL's Wireless Communication Reference Website Slide Show

Davenport & Root showed for E R(t)R(t + t)

where F[ a, b, c ; d] is the hypergeometric function

Using a second order series expansion of F[ a, b, c ; d]:

This approximation gives 3% error:

Envelope Autocorrelation

JPL's Wireless Communication Reference Website © Jean-Paul M.G. Linnartz, 1993, 1995.