Interference Analysis for Coexistence of Terrestrial Networks With Satellite Services

The integration of millimeter wave and higher frequencies into 5G and 6G networks raises concerns about potential conflicts with existing satellite services that operate in the same or adjacent frequency bands. This paper analyzes the co-channel interference and out-of-band (OOB) leakage power from terrestrial networks to satellites, and offers design criteria for terrestrial networks to protect existing satellite services. Specifically, we establish the power spectral density of a multicarrier transmitted signal, enabling us to derive the in-band and OOB emission powers for arbitrary pulse shaping and interpolation filters employed in a terrestrial transmitter. We then establish the cumulative distribution function (CDF) of the aggregated interference from terrestrial networks to a satellite receiver using stochastic geometry tools. Based on this CDF, we derive closed-form expressions that impose limits on terrestrial node density and spectrum emission masks, ensuring a near-zero satellite outage probability. By defining an interference threshold based on satellite protection criteria, our analysis enables the identification of an optimal trade-off between terrestrial node density and transmit power, providing robust theoretical guidance for formulating regulations pertaining to terrestrial networks. Extensive simulations validate our analysis results, demonstrating as an example the feasibility of cellular coexistence with LEO satellites in the 47.2-50.2 GHz band. Our approach effectively controls both in-band interference from a terrestrial network to fixed satellite services and OOB interference to passive Earth exploration satellite services in the adjacent band, while satisfying the required satellite interference thresholds.