Doppler spread associated with a Rayleigh or fast fading channel established
between a radio base station and a mobile radio station is estimated. In particular,
the Doppler spread is estimated through calculation of the autocorrelation function
of a sequence of complex channel estimates determined from a known sequence in
the received signal. More specifically, a sequence of complex channel estimates
obtained from the known sequence in a first sampling interval is complex conjugated
and then correlated with a sequence of complex channel estimates obtained from
the known reference in a second sampling interval which have been not been complex
conjugated. A zero crossing of the complex autocorrelation function is detected,
and the estimated Doppler spread is calculated using this zero crossing and a Bessel function.
