  This paper presents a device-to-device (D2D) user selection protocol wherein
multiple D2D pairs coexist with a cellular network. In the developed framework,
certain D2D users harvest energy and share the spectrum of the cellular users
by adopting a hybrid time switching and power splitting protocol. The D2D user
which harvests the maximum energy and achieves the desired target rate for the
cellular communication is selected to serve as a decode-and-forward (DF) relay
for the cellular user. The proposed work analyzes the impact of increase in the
number of D2D users on the performance of cellular user as well as derives an
upper bound on the time duration of energy harvesting within which best
possible rate for cellular user can be obtained. The performance of the
proposed protocol has been quantified by obtaining the closed form expressions
of outage probability.
