  This paper proposes a novel non-orthogonal multiple access (NOMA) assisted
cooperative spectrum sharing network, in which one of the full-duplex (FD)
secondary transmitters (STs) is chosen among many for forwarding the primary
transmitter's and its own information to primary receiver and secondary
receivers, respectively, using NOMA technique. To stimulate the ST to conduct
cooperative transmission and sustain its operations, the simultaneous wireless
information and power transfer (SWIPT) technique is utilized by the ST to
harvest the primary signal's energy. In order to evaluate the proposed system's
performance, the outage probability and system throughput for the primary and
secondary networks are derived in tight closed-form approximations. Further,
the sum rate optimization problem is formulated for the proposed cooperative
network and a rapid convergent iterative algorithm is proposed to obtain the
optimized power allocation coefficients. Numerical results show that FD, SWIPT,
and NOMA techniques greatly boost the performance of cooperative
spectrum-sharing network in terms of outage probability, system throughput, and
sum rate compared to that of half-duplex NOMA and the conventional orthogonal
multiple access-time division multiple access networks.
