  Substantially increasing wireless traffic and extending serving coverage is
required with the advent of sixth-generation (6G) wireless communication
networks. Reconfigurable intelligent surface (RIS) is widely considered as a
promising technique which is capable of improving the system sum rate and
energy efficiency. Moreover, full-duplex (FD) multi-input-multi-output (MIMO)
transmission provides simultaneous transmit and received signals, which
theoretically provides twice of spectrum efficiency. However, the
self-interference (SI) in FD system is a challenging task requiring
high-overhead cancellation, which can be resolved by configuring appropriate
phase shifts of RIS. This paper has proposed an RIS-empowered full-duplex
interference cancellation (RFIC) scheme in order to alleviate the severe
interference in an RIS-FD system. We consider the interference minimization of
RIS-FD MIMO while guaranteeing quality-of-service (QoS) of whole system. The
closed-form solution of RIS phase shifts is theoretically derived with the
discussion of different numbers of RIS elements and receiving antennas.
Simulation results reveal that the proposed RFIC scheme outperforms existing
benchmarks with more than 50% of performance gain of sum rate.
