RADIO RESOURCE BLOCK ASSIGNMENT FOR 4G-LTE FEMTOCELL NETWORKS IN MULTI-FLOOR BUILDINGS

The requirement of a mobile data rate and ubiquitous network access for an indoor environment has been increasing continuously. A long term evolution allows femtocell base stations as a potential solution which can improve not only indoor coverage but also data rates. However, one of major challenges is the increase of inter-cell interference caused by the neighboring femtocell base stations that share the same radio resource blocks. In this paper, we formulate the optimization problem as a linear programming on radio resource block assignment for 4G-long term evolution femtocell networks in multi-floor buildings. We separate the problem formulation into 2 phases. The first phase aims to assign a user to the optimal femtocell base station in order to maximize a received signal strength for a user in the service area. Then, in the second phase, the objective is to maximize the number of the radio resource blocks that is assigned to each femtocell base station from the first phase's solution. Moreover, the proposed technique can guarantee the quality of services in terms of signal to interference plus noise ratio and signal coverage. The experimental results illustrate that the proposed technique can achieve 100% service coverage throughout the service area. Furthermore, the proposed technique can reduce the inter-cell interference and improve maximum downlink throughput by up to 86.11%.