Modelling of Multi-Tier Handover in LiFi Networks

This paper presents a two-tier LiFi network and analyses the cross-tier handover rate between the primary and secondary cells. Based on the semiangle at half illuminance of the primary and secondary cells, we propose coverage model for the secondary cells. Using stochastic geometry, closed-form expressions are derived for the cross-tier handover rate and sojourn time in terms of the received optical signal intensity, time-to-trigger and user mobility. The analytical models are validated with simulation results.