Interference characterization of local 5G/6G networks operating in locally licensed shared spectrum bands

This thesis reviews the resulting interference scenarios when Local 5G/6G networks operate in locally licensed frequency bands, where incumbent spectrum users exist. Local 5G/6G networks are cellular communication networks operating in geographically restricted areas, deployed by various stakeholders, including Mobile Network Operators, to serve different user groups with different needs. Representative interference scenarios that impact local 5G/6G network deployments are simulated using the SEAMCAT tool, which is used by regulators in Europe for spectrum sharing studies. The recent report from the Electronic Communications Committee of the European Conference of Postal and Telecommunications Administrations is used to validate the developed simulation models in the 3.8-4.2 GHz band. Sensitivity analysis is performed to quantify the impact of key parameters on the required separation distance between the victim system base station and the interfering system base station to meet the protection criteria of the victim system. The results show that separation distances in the order of 10 km are needed between local 5G/6G networks considering the downlink-to-uplink interference scenario and 100 km between local 5G/6G network and incumbent fixed service system with considered assumptions. Furthermore, under the considered assumptions, the required separation distance between two local 5G/6G networks can be significantly reduced when advanced directive antennas are used instead of basic peak gain antennas. For instance, in the downlink-to-downlink interference scenario, the required separation distance decreases from 5.70 km to 0.85 km for a protection criterion of 0 dB and from 7.60 km to 1.30 km for a protection criterion of -6 dB.