LEO Constellation Systems: Design, Analysis and Application

DURATION: THREE DAYS
COURSE NO.: 2030

This course brings you up to date on all the subtleties of a commercial space constellation design, and the impacts of constellation configuration on the spacecraft design. Mission requirements drive the constellation selection process, and they include payload needs and program financial constraints. Specifically, cost considerations associated with launch vehicle performance must be considered. Similarly, payload requirements typically drive both the spacecraft pointing and power requirements, directly affecting attitude control. These then impact the vehicle propulsion, thermal and TT&C performance. Implementation of the design choices to resolve these issues is directly affected by the unique considerations associated with the LEO orbit configuration selected. Methods for resolving these systems considerations are presented, based on current and projected commercial space technologies.

COURSE MATERIALS:
Include the text "Space Mission Analysis and Design" by James R. Wertz and Wiley J. Larson, plus extensive notes and reference materials.

This material is essential for spacecraft engineers, system engineers, program managers, and other professionals requiring a working knowledge of the potentials, limitations and considerations required to capitalize on this newest growth area of space utilization.

Fundamentals of orbit mechanics, with emphasis on the impacts on LEO constellation design. Methods for evaluation of constellations for mission considerations. Impact of various constellations for mission considerations. Impact of various constellations on spacecraft subsystems design attitude control, power, propulsion, TT&C, and thermal. Operational considerations unique to constellation establishment and operation.

1. Introduction and Review of Fundamentals.
   

   Basic definitions. Review of mathematical principles. Laws of Kepler and Newton. Coordinate systems.

2. Perfect and Perturbed Orbits.
   

   Disturbance sources, natural, induced, and combined. Disturbance effects. Orbit achievement. Injection errors.

3. Candidate Constellation Orbits.
   

   LEO, HEO, and GEO. Altitude and inclination effects. Constellation configurations. Walker patterns. Adams/Rider patterns. Mission trades.

4. Candidate Payloads and Implications.
   

   Requirements. Coverage and visibility. Systems impacts. Power and attitude control. Thermal control and operations.

5. Attitude Control Subsystems.
   

   Candidate configurations. Candidate sensors. Candidate actuators. System evaluation.

6. Operations.
   

   Payload operations. Bus maintenance. Command and telemetry processing. Orbit determination and maintenance.

7. Power Subsystems.
   

   Candidate technologies and configurations. Array pointing. Battery considerations. Orbit impacts. System evaluation.

8. Propulsion Subsystems.
   

   Requirements. Candidate technologies and configurations. Implementation considerations. Flight operations.

9. Thermal Control.
   

   Candidate technologies and configurations. Orbit impacts. System evaluation.

10. Tracking, Telemetry, and Control (TT&C).
    

    Requirements. RF configuration. Baseband configuration.