Mathematical analysis for maximization of cell capacity using partial frequency reuse in LTE network

Abstract

The huge increase of high bandwidth demanding applications like interactive gaming, video streaming etc. over wireless channel and exponential growth of average mobile user population raise need of higher spectral density and cell capacity. The 4th Generation (4G) wireless network standardized as Long Term Evolution (LTE) utilizes advantages Orthogonal Frequency Division Multiple Access (OFDMA), where each cell of the network uses same frequency band, i.e Frequency Reuse equal to `1'. This leads to very high inter-cell interference (ICI) for the users at the edges of the cell and results in drastic decrease in cell capacity. To overcome ICI, Partial Frequency Reuse (PFR) method is used. Our paper presents intense mathematical calculations for optimization of cell capacity considering higher number of users near cell center. The cell partitioning radius is the variable parameter considered for mathematical integration operation for optimization problem. Assuming initial stationary position of a user nearby base station we use optimization for percentage of bandwidth reassigned to the cell-center region from partial frequency reuse region. As presented in this paper the variable user position from the base station is considered later to evaluate the optimization problem completely for demonstration of tradeoff between cell capacity and cell partitioning radius. We have simulated the rigorous mathematical expressions using Matlab scripting.