  We compute Shannon capacity of nonlinear channels with regenerative elements.
Conditions are found under which capacity of such nonlinear channels is higher
than the Shannon capacity of the classical linear additive white Gaussian noise
channel. We develop a general scheme for designing the proposed channels and
apply it to the particular nonlinear sine-mapping. The upper bound for
regeneration efficiency is found and the asymptotic behavior of the capacity in
the saturation regime is derived.
