  Simultaneous localization and mapping (SLAM) provides user tracking and
environmental mapping capabilities, enabling communication systems to gain
situational awareness. Advanced communication networks with ultra-wideband,
multiple antennas, and a large number of connections present opportunities for
deep integration of sensing and communications. First, the development of
integrated sensing and communications (ISAC) is reviewed in this study, and the
differences between ISAC and traditional communication are revealed. Then,
efficient mechanisms for multi-domain collaborative SLAM are presented. In
particular, research opportunities and challenges for cross-sensing,
cross-user, cross-frequency, and cross-device SLAM mechanisms are proposed. In
addition, SLAM-aided communication strategies are explicitly discussed. We
prove that the multi-domain cooperative SLAM mechanisms based on hybrid sensing
and crowdsourcing can considerably improve the accuracy of localization and
mapping in complex multipath propagation environments through numerical
analysis. Furthermore, we conduct testbed experiments to show that the proposed
SLAM mechanisms can achieve decimeter-level localization and mapping accuracy
in practical scenarios, thereby proving the application prospect of
multi-domain collaborative SLAM in ISAC.
