1. Different Coverage Patterns for a Single Satellite and Constellation of Satellites in Real Time with the STK Pedro A. Capó-Lugo Graduate Student Dr. Peter Bainum (HU) Dr. Peter Bainum (HU) Master’s Thesis Advisor Department of Mechanical Engineering Howard University

2. Introduction Define the Classical Orbital Elements and the Laws of Kepler and Newton. Define the Classical Orbital Elements and the Laws of Kepler and Newton. Introduction and simulation with the Satellite Tool Kit (STK) Software. Introduction and simulation with the Satellite Tool Kit (STK) Software. Show different coverage patterns and communication architectures with the use of the STK. Show different coverage patterns and communication architectures with the use of the STK.

3. Classical Orbital Elements Kepler’s Laws of Planetary Motion Newton’s Law of Motion c

5. Satellite Orbits Polar Orbit Low Earth Equatorial Orbit Geostationary Orbit Molniya Orbit

6. Single Satellite vs. Constellation One Power System One Power System One Attitude Control System One Attitude Control System One Telemetry System One Telemetry System Single Launch Vehicle Single Launch Vehicle Carry Larger and more complex instruments. Carry Larger and more complex instruments. Minimized Costs Minimized Costs Provide Better and Continuous Coverage over all or part of the Earth Provide Better and Continuous Coverage over all or part of the Earth High reliability if a satellite is lost High reliability if a satellite is lost More survivability More survivability Vary geometries or configuration. Vary geometries or configuration. Smaller and simpler satellites Smaller and simpler satellites High costs High costs

7. Communications Architecture Arrangement and configuration of different subsystems (antenna, receiver, transponder,etc.) communicating from the Earth to the Satellite. Arrangement and configuration of different subsystems (antenna, receiver, transponder,etc.) communicating from the Earth to the Satellite. Architecture depends on Three Basic and Important Objectives: Mission Objectives, Data Rates, Uplink and Downlink Architecture depends on Three Basic and Important Objectives: Mission Objectives, Data Rates, Uplink and Downlink Know the different subsystems to complete the communication requierments with the satellite. Know the different subsystems to complete the communication requierments with the satellite.

8. STK Software Used to simulate satellite orbits in real time. Used to simulate satellite orbits in real time. Synthesize the positioning of the ground antenna once the orbit has been defined. Synthesize the positioning of the ground antenna once the orbit has been defined. Used to establish communication time intervals with the satellite. Used to establish communication time intervals with the satellite. Have a three dimensional window to visualize the satellite orbit. Have a three dimensional window to visualize the satellite orbit.

9. Molniya Orbit Has a period of 12 hours. Has a period of 12 hours. Has an altitude of 40,000 km at apogee and an altitude of 500 km at perigee. Has an altitude of 40,000 km at apogee and an altitude of 500 km at perigee. Covers the north polar areas for a period of 8 hours. Covers the north polar areas for a period of 8 hours. Has an inclination angle of 63.14 degrees. Has an inclination angle of 63.14 degrees.

10. Iridium Constellation Has an altitude of 700 km. Has an altitude of 700 km. Has 6 orbital planes with 11 satellites per orbital plane. Has 6 orbital planes with 11 satellites per orbital plane. Used for phone satellite communication. Used for phone satellite communication. Can communicate to any place on the Earth. Can communicate to any place on the Earth.

11. Tetrahedron Configuration NASA GSFC Proposed Benchmark Configuration Has an altitude of 12 times the radius of the Earth at apogee. Has an altitude of 12 times the radius of the Earth at apogee. Has the same configuration at apogee. Has the same configuration at apogee. Generate multiple measurements of the magnetic field of the Earth. Generate multiple measurements of the magnetic field of the Earth.

12. Molniya Orbit

13. Iridium Constellation

14. Tetrahedron Configuration

16. Conclusion Knowledge of the Classical Orbital Elements. Knowledge of the Classical Orbital Elements. Understand how to design a communication architecture for a satellite or group of satellites. Understand how to design a communication architecture for a satellite or group of satellites. Know the difference between a constellation and a single satellite. Know the difference between a constellation and a single satellite. Simulations with the STK software are very accurate. Simulations with the STK software are very accurate.