Laser-Based Indoor Wireless Communication for Mobile Devices Aided by Stabiliser: Mobility and Outage Analysis

Light-fidelity (LiFi) is a networked optical wireless communication (OWC) solution to achieve multi-Gbps data rates for mobile optical communications. Unlike typical radio frequency (RF) wireless systems, the OWC channel is not isotropic, which means that the device orientation considerably affects the channel gain, especially for mobile users. In this study, a practical uplink LiFi scenario is analysed in which a number of mobile devices equipped with eye-safe laser-based transceivers transmit multi-Gbps data streams wirelessly to receivers on the ceiling. Ten models for five different types of user mobility with and without stabiliser have been developed on the basis of experimental measurements. Using the proposed models, the capability of stabilisers to mitigate the pointing error due to user mobility is investigated. It is shown that the device orientation may be modelled as Laplace, Gaussian, uniform distributions, or sinusoidal functions. Moreover, an orientation-based random waypoint (ORWP) mobility model is used to assess the performance of the LiFi system in terms of outage probability. The results show that using a stabiliser on mobile devices improves outage performance significantly, and it is feasible to reduce the number of uplink receivers while retaining the required outage performance.