The invention discloses a time frequency overlap
signal parameter
estimation method under Alpha stable distribution
noise. The steps include: computing generalized fourth order circulation cumulants of the time frequency overlap
signal under Alpha stable distribution
noise and setting generalized fourth order circulation cumulant magnitude spectra beta-|GC<beta>(r, 40)| and beta-|GC<beta>(r, 42)| to zero in a small neighbourhood [0,
delta0] in which the
cycle frequency beta=0; detecting the highest spectrum lines P1 and P1* in beta-|GC<beta>(r, 40)| and beta-|GC<beta>(r, 42)| respectively according to a
discrete spectrum line detection method, then setting the amplitude value GCmax of the spectrum line in beta-|GC<beta>(r, 40)| and the amplitude value GCmax* of the spectrum line in beta-|GC<beta>(r, 42)| to zero in small neighbourhoods [P1-
delta0, P1+
delta0] and [P1*-delta0, P1*+delta0], and thus cycle frequencies corresponding to P1 and P1* being a carrier
wave velocity fc1 and a code element velocity fb1 of one of
signal components of the time frequency overlap signal; and under the conditions that the code element velocities and the carrier wave frequencies of the overlap signal components are different, detecting the code element velocities of other signal components of the time frequency overlap signal in sequence according to the
discrete spectrum line detection method, till the amplitude value GCk+1* of the (k+1)th spectrum line in beta-|GC<beta>(r, 42)| being smaller than GCmax* / 2, judging the number of mixed signals to be k at this time, and detecting the carrier wave frequencies of other signal components of the time frequency overlap signal in sequence according to the
discrete spectrum line detection method.