New in SC Modeler 4.1

1. Enhanced Shortest Path Search
Significant improvements have been made to the shortest path search in SC Modeler 4.1, enabling the creation of responsive animated simulations, dynamic routing visualization, and performance analysis of large-scale multi-layer satellite networks.
The table below displays the frame refresh time for animated simulations of dynamic routing between two ground stations situated at opposite points on Earth, one at 45°N and the other at 45°S. For constellations containing thousands of satellites, this time is primarily determined by satellite movement propagation and the shortest path search.
Frame Refresh Time - Satellite Network
Number of Satellites Orbital Structure ISL per Satellite Orbit Propagator Frame Refresh Time (sec)
5,000 Kinematically Regular ("Walker delta"), 100 orbital planes 4 Two-Body Keplerian with J2 Perturbations 0.08
10,000 Kinematically Regular ("Walker delta"), 100 orbital planes 4 Two-Body Keplerian with J2 Perturbations 0.24
4,868 Starlink, TLE-defined, 4,868 orbital planes Unrestricted, 500+ potential ISL per satellite (this network topology does not reflect the actual one and was chosen for application performance validation only) SGP4/SDP4 0.14
Notes:
  • PC Configuration: Laptop with an 11th generation Intel Core i7 processor, 2.80GHz, 16 GB RAM, integrated video card.
  • Routing policy: The total length of the path from the source node to the destination node.
  • Orbit altitude for the first two constellations: 485 km, inclination - 53.75°.
  • Uplink/Downlink field-of-view: Simple conic with a minimum ground elevation angle of 25°. Using instead a custom sensor defined by the Azimuth-Elevation mask resulted in a 5 to 15% increase in the Frame Refresh Time.
  • The Network Topology Tools were used to define the network topology for kinematically regular constellations.
  • The Starlink TLE dataset contained currently active and decayed satellites. Decayed satellites have been excluded from the path search.
  • The frame refresh rate was nearly identical for all three constellation visualization modes - 2D, 3D, and 3D OpenGL.
  • The Total Path Delay task was turned on and running during simulations, displaying the results in a dedicated area of the application window.
2. Ground-Based Relay Stations
SC Modeler 4.1 introduces the possibility to explore the use of ground-based relay stations that can forward data between satellites. This capability can either complement or replace intersatellite links within a satellite network.
The application allows for the addition of tens of thousands of ground relay stations to a satellite network.
Frame Refresh Time - Satellite Network with Ground Relays
Number of Relays Number of Satellites Orbital Structure ISL per Satellite Orbit Propagator Frame Refresh Time (sec)
5,150 5,000 Kinematically Regular ("Walker delta"), 100 orbital planes 4 Two-Body Keplerian with J2 Perturbations 0.11
5,150 4,868 Starlink, TLE-defined, 4,868 orbital planes - SGP4/SDP4 0.25
42,000 4,868 Starlink, TLE-defined, 4,868 orbital planes - SGP4/SDP4 0.34
Notes:
  • Ground relays were evenly distributed within North America, covering latitudes between 25°N and 60°N. Two ground stations (user terminals) were placed near the northwest and southeast corners of the area.
  • Only "representative" ground relays (less than 10% of the total) have been displayed. All satellites and satellite orbits (in 3D and 3D OpenGL modes) have been visualized.
  • The program conducted the shortest path search at each time step during simulation. Switching to a delayed search mode, which postpones path refresh until either the route becomes invalid or for a specified period of time, significantly decreases the average Frame Refresh Time.
3. Routing Settings Tool
The Routing Settings tool now offers the ability to define a balanced hierarchical search and choose between the Dijkstra algorithm, Breadth-First Search, and A* Search, depending on the selected routing policy.
4. Network Topology Tools Usability Improvements
5. TLE Update Utility
SC Modeler 4.1 includes the TLE Update Utility, which provides automatic updates of TLE database records.
Note: A Space Track (space-track.org) account is required to use this tool.
6. Route Explorer
7. Many other feature improvements and bug fixes