The rise of large LEO constellations has led to several challenges, not only related to the increasing congestion of specific orbits. Indeed, this trend also has a profound impact on the management and regulation of the use of radio frequency spectrum, a scarce natural resource with finite capacity, whose risk of shortage notably grows. The critical role played by the satellite industry in the telecommunication sector and the rising need to better integrate space and terrestrial networks are demonstrated by the recent inclusion of non-terrestrial networks in standardisation documents, such as, for instance, the 3rd Generation Partnership Project (3GPP) Release 17, “5G for space: the NR NTN standard” published in March 2022, and further complemented with the ITU Working Party 4B´s developing standards for the satellite component of International Mobile Telecommunications (IMT) 2022.
Among other challenges, the problem of orbit and spectrum reservation without actual use, and the phenomena of spectrum warehousing and overfilling with so-called paper satellites are incrementally being considered within ITU. Resolution 49 to the Radio Regulations (RR) on administrative due diligence applies to satellite networks in the FSS, MSS, and BSS that are subject to ITU coordination procedure, and requires specific information (in the application of RR No. 11.48) to be submitted within 30 days after the end of the regulatory deadline (RR No. 11.44), and otherwise resulting in the suppression of the submission.
Focusing on the rising issue of spectrum speculation in the context of large constellations, the practice of the ITU-R Bureau (BR) on non-GSO satellite systems is reflected in the Rules of Procedure for RR No. 11.44C. The latter state that a frequency assignment to space stations in any non-GSO system has been brought into use (BIU) when one satellite with the capability of transmitting or receiving that frequency assignment is deployed and “maintained on one of the orbital plane(s) for a continuous period of 90 days”. During WRC-19, participants have agreed on a new regulatory procedure, under which non-GSO systems shall deploy 10% of their constellations within two years after the end of the regulatory period for bringing into use, 50% within five years, and complete the deployment within seven years (Resolution 35). Within the context of the WRC-23 agenda item 7, the ITU-R Working Party 4A will have to continue exploring new mechanisms for BIU frequency assignments to non-GSO constellations. The objective should be to prevent spectrum warehousing, while also considering operational requirements for the deployment of non-GSO systems and the functioning of the coordination procedure.