  This paper studies a scalar Gaussian wiretap channel where instead of an
average input power constraint, we consider a peak amplitude constraint on the
input. The goal is to obtain insights into the secrecy-capacity and the
structure of the secrecy-capacity-achieving distribution. Capitalizing on the
recent theoretical progress on the structure of the secrecy-capacity-achieving
distribution, this paper develops a numerical procedure, based on the gradient
ascent algorithm and a version of the Blahut-Arimoto algorithm, for computing
the secrecy-capacity and the secrecy-capacity-achieving input and output
distributions.
