Movable Access Points in Visible Light Communications: Opportunities, Challenges and Future Directions

Abstract

Visible light communication (VLC) is expected to be a key component of future wireless networks due to its abundant license-free spectrum, inherent high-level security, and the already deployed lighting infrastructure. VLC performance, however, depends on device orientation and the availability of an unobstructed line-of-sight (LoS) link, with transmitter semi-angle and receiver field-of-view (FoV) further affecting alignment, coverage, and reliability. Reconfigurable intelligent surfaces (RISs) can mitigate blockages, orientation issues, and mobility challenges, but their data rates remain far below those of direct LoS links. This article introduces the novel concept of movable access points (MAPs)-aided VLC systems, where dynamically repositioned APs provide new degrees of freedom to ensure LoS connectivity, and transmitter-receiver alignment while providing ultra-high data rates for mobile users. Simulation results show MAPs outperform RIS-aided, fixed-AP, and RIS-only VLC systems in dynamic environments. The article also outlines key challenges and future research directions, including integration with emerging wireless technologies.