Sharing of Satellite Telecommunication Services in the 12.75–13.25 GHz Band for the Uplink

There is a great demand for mobility services in the Ku-band uplink; however, only 500 MHz is available for this type of service (14–14.5 GHz). With the additional allocation of a spectrum between 12.75 and 13.25 GHz, the satellite industry will be able to meet this need for additional capacity; however, the band must be harmonized because there are already assigned primary services that need to be protected against interference. This article presents the study and evaluation of the spectrum sharing and compatibility of the fixed (primary) satellite services allocated to the frequency band from 12.75 to 13.25 GHz with the mobile (secondary) satellite services to onboard aircraft and vessels (ETEM); Following resolution 172 of the WRC-23 (World Radiocommunication Conference 2023) agenda, both services communicate with GSO (Geostationary Satellite Orbit) space stations through an uplink. The methodology started with the investigation of the technical specifications and characteristics of each service for the case study of Colombia, which is in region 2; then, three interference scenarios between the mentioned satellite services were identified and selected; Subsequently, a study was made of the places (Colombian cities) where cases of interference between these services may occur. Finally, the parameters to evaluate the interference were established, and it was simulated in SEAMCAT® to collect the values of the parameters of interest and make an analysis of the results obtained. These allow concluding coexistence without interference if coordination distances of 50 km, or more are met between ETEM and FSS (Fixed Satellite Service) earth stations in the uplink. Another requirement is that the transmission bandwidths must be a maximum of 7 MHz.