Migration to 28 GHz frequency with higher order sectorization in urban macro cellular environment

The main objective of this paper is to determine the difference in network performance between 2.1 GHz and 28 GHz frequency of operation, with and without considering higher order sectorization. The simulations are performed using sAGA a MATLAB based 3D ray tracing tool, an extended 3GPP antenna model and 3D building data from urban/dense urban area of Helsinki city. Three network performance metrics i.e. received signal strength, SINR, and area spectral efficiency (capacity) is investigated. The obtained results indicate that due to good propagation condition at 2.1 GHz, the mean RX level is around 18 dB better at 2.1 GHz compared with 28 GHz, even after assuming high system gain at higher frequency. The SINR is moderately deteriorated at 28 GHz with 200 MHz bandwidth. The real gain of higher order sectorization and millimeter wave communications appears in terms of increase in overall area capacity. It was found that replacing the 3-sector sites with 6-sector sites at 2.1 GHz provides only about 84.72% capacity gain, whereas migrating to 28 GHz frequency band from 2.1 GHz and utilizing 200 MHz bandwidth offers around 556% of additional capacity. This relative capacity gain is further increased to 1289% by shifting the cellular network to higher frequency along with higher order sector sites i.e. 6-sector site.