  The study of relays with the scope of energy-harvesting (EH) looks
interesting as a means of enabling sustainable, wireless communication without
the need to recharge or replace the battery driving the relays. However,
reliability of such communication systems becomes an important design challenge
when such relays scavenge energy from the information bearing RF signals
received from the source, using the technique of simultaneous wireless
information and power transfer (SWIPT). To this aim, this work studies
bidirectional communication in a decode-and-forward (DF) relay assisted
cooperative wireless network in presence of co-channel interference (CCI). In
order to quantify the reliability of the bidirectional communication systems, a
closed form expression for the outage probability of the system is derived for
both power splitting (PS) and time switching (TS) mode of operation of the
relay. Simulation results are used to validate the accuracy of our analytical
results and illustrate the dependence of the outage probability on various
system parameters, like PS factor, TS factor, and distance of the relay from
both the users. Results of performance comparison between PS relaying (PSR) and
TS relaying (TSR) schemes are also presented. Besides, simulation results are
also used to illustrate the spectral-efficiency and the energy-efficiency of
the proposed system. The results show that, both in terms of spectral
efficiency and the energy-efficiency, the two-way communication system in
presence of moderate CCI power, performs better than the similar system without
CCI. Additionally, it is also found that PSR is superior to TSR protocol in
terms of peak energy-efficiency.
