Abstrakt: |
Summary: In this work, the current power‐flux density limits in Article 21 of the ITU‐R Radio Regulations for non‐geostationary satellite orbit (GSO) systems operating in the 3.7‐4.2 GHz band are analyzed. These limits aim the protection of fixed service receivers, operating in the same frequency band, from the interference produced by non‐GSO satellite systems. The analysis was motivated by Resolution 157 of the World Radiocommunication Conference 2015, that recognized the need for a revision of Article 21 with a view to enabling non‐GSO systems to operate in these fixed‐satellite service frequency bands while ensuring that existing primary services are protected. In the analysis, 5 different circular Walker Delta type satellite constellation structures, adequately chosen, are considered, and the results show that the current power‐flux density (pfd) limits may impose undue constraints to non‐GSO systems operating in this band. Therefore, a methodology to investigate a more adequate pfd limiting mask is presented and used to generate an alternative mask. An evaluation of the proposed pfd mask shows that it does not impose unnecessary constraints to the non‐GSO satellite systems. This, along with other facts, indicates that the proposed pfd limits are, indeed, much more adequate than the current ones. [ABSTRACT FROM AUTHOR] |