Analysis of upgrade options for the structure of orbital grouping of the GLONASS system to ensure its competitiveness

A synthesis of possible options for upgrading the orbital grouping of the global navigation satellite system GLONASS was carried out based on the following modernization principles: an increase the number of spacecrafts, while maintaining the three-plane structure and changing the height and inclination of the orbits; increase the number of spacecrafts, while maintaining the parameters of the orbits; increasing the number of spacecrafts with the introduction of 3 additional planes to accommodate antipodal spacecraft in them (additional planes are located between the main ones). The characteristics of the navigation field of the variants of the synthesized orbital groupings were modeled: the basic orbital group of 24 spacecrafts with their uniform placement in 3 planes (GLONASS-24); from 27 spacecrafts with their uniform placement in 3 planes; from 30 spacecrafts with their uniform placement in 3 planes; from 30 spacecrafts based on GLONASS-24, where 2 antipodal spacecrafts are added to each plane; from 30 spacecrafts on the basis of GLONASS-24 with the organization of additional three planes, in which 2 spacecrafts are added each; from 30 spacecrafts uniformly placed in 6 planes; from 36 spacecrafts uniformly placed in 3 planes; from 36 spacecrafts based on GLONASS-24, in which 3 additional planes are added between the standard planes, in which 4 spacecrafts are added each; from 36 spacecrafts on the basis of GLONASS-24, where 4 spacecrafts are added to each regular plane; from 36 spacecrafts based on GLONASS-24, in which 2 antipodal spacecrafts were added to each regular plane, and 2 antipodal spacecrafts were added to 3 additional planes. Based on the analysis of the characteristics of the navigation field, preference was given to the six-plane orbital group of 30 spacecrafts, built on the basis of GLONASS-24 with the organization of three additional planes.