  The millimeter-wave (mmWave) communication technology, which employs
large-scale antenna arrays, enables inherent sensing capabilities. Simultaneous
localization and mapping (SLAM) can utilize channel multipath angle estimates
to realize integrated sensing and communication design in 6G communication
systems. However, existing works have ignored the significant overhead required
by the mmWave beam management when implementing SLAM with angle estimates. This
study proposes a joint beam management and SLAM design that utilizes the strong
coupling between the radio map and channel multipath for simultaneous beam
management, localization, and mapping. In this approach, we first propose a
hierarchical sweeping and sensing service design. The path angles are estimated
in the hierarchical sweeping, enabling angle-based SLAM with the aid of an
inertial measurement unit (IMU) to realize sensing service. Then, feature-aided
tracking is proposed that utilizes prior angle information generated from the
radio map and IMU. Finally, a switching module is introduced to enable flexible
switching between hierarchical sweeping and feature-aided tracking. Simulations
show that the proposed joint design can achieve sub-meter level localization
and mapping accuracy (with an error < 0.5 m). Moreover, the beam management
overhead can be reduced by approximately 40% in different wireless
environments.
