  The following paper models a secure full duplex (FD) integrated sensing and
communication (ISAC) scenario, where malicious eavesdroppers aim at
intercepting the downlink (DL) as well as the uplink (UL) information exchanged
between the dual functional radar and communication (DFRC) base station (BS)
and a set of communication users. The DFRC BS, on the other hand, aims at
illuminating radar beams at the eavesdroppers in order to sense their physical
parameters, while maintaining high UL/DL secrecy rates. Based on the proposed
model, we formulate a power efficient secure ISAC optimization framework
design, which is intended to guarantee both UL and DL secrecy rates
requirements, while illuminating radar beams towards eavesdroppers. The
framework exploits artificial noise (AN) generation at the DFRC BS, along with
UL/DL beamforming design and UL power allocation. We propose a beamforming
design solution to the secure ISAC optimization problem. Finally, we
corroborate our findings via simulation results and demonstrate the
feasibility, as well as the superiority of the proposed algorithm, under
different situations. We also reveal insightful trade-offs achieved by our
approach.
