Abstract:
|
This correspondence studies the formulation of members of
the Cohen-Posch class of positive time-frequency energy distributions.
Minimization of cross-entropy measures with respect to different priors
and the case of no prior or maximum entropy were considered. It is
concluded that, in general, the information provided by the classical
marginal constraints is very limited, and thus, the final distribution
heavily depends on the prior distribution. To overcome this limitation,
joint time and frequency marginals are derived based on a "direction
invariance" criterion on the time-frequency plane that are directly related
to the fractional Fourier transform. |