We present a deconvolution technique to obtain the evolutionary spectrum (E
S) of nonstationary signals by deconvolving the blurring effects of the tim
e-frequency distribution (TFD) kernel from bilinear TFD's. The resulting sp
ectrum is non-negative and has desirable properties such as higher resoluti
on and higher concentration in time frequency. The new technique is computa
tionally more efficient compared with the recently proposed entropy-based d
econvolution technique, and, unlike the entropy method, it is not restricte
d to deconvolution of spectrograms with Gaussian windows. This makes the me
thod applicable to deconvolving many of the bilinear time-frequency distrib
utions.