  In this paper, we initiate the study of rate-splitting multiple access (RSMA)
for a mono-static integrated sensing and communication (ISAC) system, where the
dual-functional base station (BS) simultaneously communicates with multiple
users and detects multiple moving targets. We aim at optimizing the ISAC
waveform to jointly maximize the max-min fairness (MMF) rate of the
communication users and minimize the largest eigenvalue of the Cram\'er-Rao
bound (CRB) matrix for unbiased estimation. The CRB matrix considered in this
work is general as it involves the estimation of angular direction, complex
reflection coefficient, and Doppler frequency for multiple moving targets.
Simulation results demonstrate that RSMA maintains a larger communication and
sensing trade-off than conventional space-division multiple access (SDMA) and
it is capable of detecting multiple targets with a high detection accuracy. The
finding highlights the potential of RSMA as an effective and powerful strategy
for interference management in the general multi-user multi-target ISAC
systems.
