  Simultaneous reuse of spectral resources by uplink and downlink, denoted as
in-band full duplex (FD) communication, is promoted to double the spectral
efficiency when compared to its half-duplex (HD) counterpart. Interference
management, however, remains challenging in FD cellular networks, especially
when high disparity between uplink and downlink transmission powers exists. The
uplink performance can be particularly deteriorated when operating on channels
that are simultaneously occupied with downlink transmission. This paper
considers a cellular wireless system with partial spectrum overlap between the
downlink and uplink. The performance of the system becomes, therefore, a
function of the overlap fraction, as well as the power level of both the uplink
and downlink transmissions. The paper considers the problem of maximizing an
overall network utility to find the uplink/downlink transmission powers and the
spectrum overlap fraction between the uplink and downlink spectrum in each
cell, and proposes solving the problem using interior point method. Simulations
results confirm the vulnerability of the uplink performance to the FD
operation, and show the superiority of the proposed scheme over the FD and HD
schemes. The results further show that explicit uplink and downlink performance
should be considered for efficient design of cellular networks with overlapping
uplink/downlink resources.
