Machine Learning Based Handover Management for LTE Networks with Coverage Holes
Machine learning, coverage holes, LTE, Handover.
Legacy strategies have been adapted to fulfill the increasing demand for wireless broadband internet access. One of them, the Hierarchical Cell Structure (HCS), that is already in use in LTE-A and it is considered for the 5G, consists in the deployment of several types small cells under the umbrella of macrocells, creating an overlaid coverages. Due to their low power and bellow-rooftop-level, sometimes indoor base stations, the small cells are severely affected by the surrounding obstacles, making the perceived Quality of Experience (QoE) of the users subject to fast variations, thus rendering ineffective the classical approaches to mobility management, that are unable to predict those severe fading situations (coverage holes). Considering the amount of available information on the network performance and the evolution of real-time processing capabilities, the enhancement of LTE functionalities such as the handover, by means of machine learning algorithms became possible. This work proposes and evaluates the performance of a machine learning based approach to handover in the presence of signal-blocking obstacles. Our machines learn from experience and they are, therefore, able to choose the eNB that will most likely offer the user the highest long term QoE after the handover procedure, even in severe propagation conditions. The performance evaluation shows that the proposed schemes substantially improves the user's QoE.