Access point assignment in hybrid LiFi and WiFi networks in consideration of LiFi channel blockage

Abstract

As a promising complement to the increasingly congested wireless fidelity (WiFi) system, light fidelity (LiFi) has recently drawn massive attention due to the wide and unregulated visible light spectrum. Also, the light waves cannot penetrate walls which enables interference avoidance between compartments. Meanwhile, LiFi access points (APs) have a much shorter range, relative to WiFi APs. A hybrid network can combine the high-speed transmission of LiFi and the ubiquitous coverage of WiFi. For such a network, access point assignment (APA) becomes challenging because of the completely overlaying coverage of different networks. In addition, LiFi is susceptible to channel blockage due to opaque obstacles, adding difficulties to the APA issue. In this paper, a novel APA method is proposed for hybrid LiFi and WiFi networks in consideration of LiFi channel blockage for the first time. By exploiting users' statistical information of channel blockage, the proposed method formulates the issue as an optimisation problem that maximises the system throughput over a period of time. Results show that the proposed method can improve throughput by up to 90% over the conventional load balancing method.