Simulation and Analysis of Simultaneous Water-Filling Allocation Based on Fractional Frequency Reuse for 19-Cell Network

In frequency allocation for 5G communications, the power of the signal and the interferences from other base stations are crucial factors of its quality, such as the network capacity and the signal to noise ratio. Reusing the channels is an excellent way to reduce the cost, but it also causes interferences. Therefore, optimising the methods of the allocation remains critical. This paper shows that the combination of Simultaneous Water-Filling and Fractional Frequency Reuse with specific reuse factors of Integer Frequency Reuse applied to the centre part of the cells performs compellingly. Besides, the reuse factor should be chosen carefully to avoid both interference and the separation of total power. The results demonstrate how Simultaneous Water-Filling works and how the reuse factor plays a role in preventing disturbances among multiple base stations. The result shows, in Fractional Frequency Reuse network, the method with Simultaneous Water-Filling is always better than that without it. Besides, the combined method works well when the reuse factor is low (being 1) or high (being 7), but not good when the reuse factor is medium (being 3).