Numerical approximation of millimeter-wave frequency sharing between cellular systems and fixed service systems

This paper presents numerical analysis and simulation results in order to study the impact of interference between fixed service (FS) systems and 5G cellular networks at 28 GHz, 38 GHz, and 60 GHz millimeter-wave (mmWave) bands. For this study, two different scenarios were considered, i.e., the aggregation of interference from small cells into an FS receiver from (i) base stations (BSs) to their associated user equipment (UE) (downlink); (ii) from UEs to their associated BSs (uplink). The simulation results determined how much interference rejection is required to protect the operation of the FS. This study is essential when using mmWave technologies in cellular networks, to determine whether the newly deployed cellular systems can co-exist with pre-deployed FS systems or not. This paper presents closed-form numerical approximation results with Taylor series approximation along with intensive simulation results. Finally, this paper confirmed that the numerical approximation results were precise, i.e., that here were only marginal differences to the intensive simulation results.