Cell Zooming for Green Mobile Networks with Vehicle-Mounted Radio Units

Many radio units (RUs) are densely deployed to compose small cells with high frequency bands in the Centralized Radio Access Network (C-RAN) architecture which prevails in the 5G mobile networks. More and more cells will be required in the era of beyond 5G and 6G to ensure wide coverage with high data rate. The concept of on-board cells, i.e. vehicle-mounted RUs, is a promising solution for future mobile networks because it enables dynamic and efficient network deployment to deal with the fluctuations in mobile traffic demand. Cell zooming has also been proposed to adaptively adjust the cell size according to fluctuating traffic load. However, it has not been considered to employ cell zooming for vehicle-mounted cells. The existing cell zooming schemes cannot be employed for vehicle-mounted cells because of their high mobility. Therefore, this paper proposes a cell zooming scheme for vehicle-mounted RUs. The goal of the proposed technique is to optimize the size of each cell according to the current distribution of RUs for reducing transmission power. It contributes for energy efficiency of mobile networks. The performance of the proposed approach was confirmed through computer simulations.