  This paper considers an orthogonal frequency division multiplexing (OFDM)
point-to-point wireless communication system with simultaneous wireless
information and power transfer. We study a receiver which is able to harvest
energy from the desired signal, noise, and interference. In particular, we
consider a power splitting receiver which dynamically splits the received power
into two power streams for information decoding and energy harvesting. We
design power allocation algorithms maximizing the spectral efficiency
(bit/s/Hz) of data transmission. In particular, the algorithm design is
formulated as a nonconvex optimization problem which takes into account the
constraint on the minimum power delivered to the receiver. The problem is
solved by using convex optimization techniques and a one-dimensional search.
The optimal power allocation algorithm serves as a system benchmark scheme due
to its high complexity. To strike a balance between system performance and
computational complexity, we also propose two suboptimal algorithms which
require a low computational complexity. Simulation results demonstrate the
excellent performance of the proposed suboptimal algorithms.
