  In this paper, we formulate two multi-objective optimization problems (MOOPs)
in orthogonal frequency-division multiple access (OFDMA)-based in-band
full-duplex (IBFD) wireless communications.~The aim of this study is to exploit
the performance trade-off between uplink and downlink where a wireless radio
simultaneously transmits and receives in the same frequency.~We consider
maximizing the system throughput as the first MOOP and minimizing the system
aggregate power consumption as the second MOOP between uplink and
downlink,~while taking into account the impact of self-interference~(SI)~and
quality of service provisioning.~We study the throughput and the transmit power
trade-off between uplink and downlink via solving these two problems.~Each MOOP
is a non-convex mixed integer non-linear programming~(MINLP)~which is generally
intractable. In order to circumvent this difficulty, a penalty function is
introduced to reformulate the problem into a mathematically tractable
form.~Subsequently,~each MOOP is transformed into a single-objective
optimization problem~(SOOP)~via the weighted Tchebycheff method which is
addressed by majorization-minimization~(MM)~approach. Simulation results
demonstrate an interesting trade-off between the considered competing
objectives.
