Resource and Mobility Management in Hybrid LiFi and WiFi Networks: A User-Centric Learning Approach

Hybrid light fidelity (LiFi) and wireless fidelity (WiFi) networks (HLWNets) are an emerging indoor wireless communication paradigm, which combines the complementary advantages of LiFi and WiFi. Meanwhile, load balancing (LB) becomes an essential and critical challenge, due to the nature of hybrid networks. The existing LB methods are mostly network-centric, relying on a central unit to make a solution for the users all at once. Consequently, the solution needs to be updated for all users at the same pace, regardless of their moving status. This would affect the network performance in two aspects: 1) a lower update frequency would compromise the connectivity of fast-moving users; 2) a higher update frequency would cause unnecessary handovers as well as hefty feedback costs for slow-moving users. Motivated by this, we investigate user-centric LB so that users can update their solutions at different paces. The research is developed upon our previous work on adaptive target-condition neural network (ATCNN), which carries out LB for individual users in quasi-static channels. In this paper, a deep neural network (DNN) model is designed to enable an adaptive update interval for each individual user. This new model is termed as mobility-supporting neural network (MSNN). Associating MSNN with ATCNN, a user-centric LB framework named mobility-supporting ATCNN (MS-ATCNN) is proposed to handle resource management and mobility management simultaneously. Results show that at the same level of average update interval, MS-ATCNN can achieve a network throughput up to 215% higher than conventional LB methods such as game theory (GT), especially for a larger number of users. In addition, MS-ATCNN costs an ultra-low inference time in sub-milliseconds, which is two to three orders of magnitude lower than the GT baseline.