Hybrid modile femtocells: the mmWave solution for 5G Moving Networks

Abstract

Mobile connectivity is a vital requirement for peoples everyday life. Users would like to have unlimited access to information for anyone, anywhere, and anytime, especially in public means of transport where they spend a lot of time travelling. The connectivity to Internet becomes difficult for passengers because public transportation vehicles suffer from the low quality signal from the outside wireless network. One of the requirements of the 5G Network is to guarantee a high level of service to users wherever they are, both at home, office, or in public means of transport. Users on the move shall have the impression that the network infrastructure follows them", in situations where they suffer from poor coverage today. A first solution to improve the broadband connectivity is to deploy more eNodeBs close to buses or train routes, but it requires high investment for providers and a higher complexity in managing the increasing number of handover. The rapid growth in the deployment of LTE femtocells for indoor use and their benefits have led many authors to propose using them even in vehicles, implementing the so-called Moving Networks. This work shows that the use of pure LTE mobile femtocells exhibits relevant issues in terms of interference and consequently poor performance in a realistic use. In order to overcome these issues, we propose to adopt the millimeter Wave (mmWave) technology in the Moving Networks, creating the Hybrid Mobile Femtocells. The new technology will satisfy the 5G requirements of enhancing the capacity and coverage for the users on the move and to enable long battery life, due to the short range transmission between the user equipments and the access point. In the thesis we discuss the concerns arising from applying mmWave communications at 60 GHz inside vehicles. We provide a new throughput analysis in order to benchmark our proposal to the solutions presented in literature. Furthermore, we analyse the system performance in two different scenarios: a sub-urban setup and in an urban configuration where different kind of cells are deployed. The results obtained by Matlab simulations, show a noticeable improvement of the global system throughput by using Hybrid Mobile Femtocells.