
90 Practical Biomedical Signal Analysis Using MATLAB
R
2002], is defined by the formula:
PLV
n,m
=
cosφ
n,m
(t)
2
+ sinφ
n,m
(t)
2
, (3.46)
where · denotes averaging over time. From the above formula one can find how
the relative phase is distributed over the unit circle. If the two signals are phase
synchronized, the relative phase will occupy a small portion of the circle, which
means high phase coherence.
Other measures of phase synchronization (PS) are based on the calculation of the
distribution of phases [Pereda et al., 2005]. In the so-called stroboscopic approach
the phase of one of the oscillators is observed at those instants where that of the