Evaluation for Cell Density of Mobile Network in Traffic-intensive Areas

As user traffic of mobile network increases, network operators should guarantee the quality of service by capacity expansion such as installation of additional cells. However, since cells have been densely deployed in traffic-intensive areas, additional cell split may not be effective due to increased interference. Therefore, it is important to evaluate the cell density and pilot pollution status to estimate the effectiveness of cell expansion in terms of cost saving. In this paper, we propose the methodology for evaluating the cell density using the pilot pollution with the signal strength and quality of serving and neighbor cells. For signal quality analysis, we introduce the signal quality indicator independent of cell load and the method for deriving threshold. Finally, pilot pollution based on area-scale and cell-scale was evaluated for each mobile network operator using the in-filed measurement data collected in the Gangnam area of Seoul, South Korea. According to the analysis of this paper, the result of the pilot pollution ratio in the sample area is 75% to 78%, and the result based on each cell is 96% to 98%.