US Naval Academy LABsats

1. US Naval Academy LABsats Bob Bruninga, WB4APR AIAA JHU/APL Educational Seminar 10 Nov 2006

2. USNA Satellites Bob Bruninga, WB4APR

3. Basic USNA’sat

4. SCIENCE USNA-0203 Digital Transponder Telemetry system has 1200/9600 baud available • STP Experimentscan interface to serial ports here • PCsat

5. The USNA Constellation

6. USNA PCSAT2 on ISS Launched Aug 2006, attached to ISS 1 Year of 3 Mbytes data per day Supported Packet and Voice Relay Returned Sept 2006

7. Our Satellites provide a low cost educational transponder supporting not only GPS position reporting but also remote WX stations and other data link experiments and other University and School Experiments. • The comm channels can potentially draw from over 30,000 experimenters for easy assessment of loading and scaling issues. • Not only the sensors and users exist, but the global Internet collection and distribution system also exists from PCSAT1 & 2.

8. SCIENCE USNA-0203 Space User Baseline PCSAT validates our links See www.ariss.net PCSAT2 User Plot 18 Apr 06 Vandegriff

9. SCIENCE USNA-0203 Global Internet Linked Ground Stations All downlinks available live on web via Participating internet linked Ground Stations www.ariss.netpcsat.aprs.org

10. Types of Labs • Antenna Labs: . . . . . . . . Link, Patterns, Gain, Beamwidth, SWR • Electrical Power sys: . . Solar Cells, batteries and Regulators • Transmitters: . . . . . . . . . TX power and antenna matching • Receivers: . . . . . . . . . . . Receiver sensitivity, selectivity and Bandwidth • Comms: . . . . . . . . . . . . . FSK, AFSK,PSK ; and TDMA and FDMA • Telemetry: . . . . . . . . . . . Signals, decoding, equations 5 channel A/D • Command / Control: . . . Using the 3 commandable ON/OFF circuits. • CPU and Experiments: . Aux serial port – processor, GPS, etc • GPS interface: . . . . . . . . Using a GPS input for position determination • Attitude Control: . . . . . . .Passive/active Magnetorquing & wheels. • Thermal Control: . . . . . . Absorbtivity, Emissivity, Conduction.

11. LABsat Examples

12. Ground Stations Laptop Ground Station for RAFT

13. Antenna Tests • Uses small 2.4 GHz camera/transmitters • First observe dipole link (1000’) • Place dipole at dish focus and measure gain • Swing dish to see Beamwidth

14. Antenna Tests Using GPS signals to plot antenna pattern of GPS Using PI network to match spacecraft antenna for best SWR

15. Antenna Tests RF LABsat model on rotor Dipole 1 Dipole 1 Rotator and S/A to plot pattern Antenna Phasing experiment

16. Transmitter Tests Power out Efficiency Temperature Spectrum and EMI

17. Receiver Tests

18. Demodulation - FSK • All Seven Student LABsats on the air • Sharing a single TDMA channel • Using FSK for demodulation

19. Demodulation - PSK Indoor LABsat RX LABsat configured as HF to UHF linear transponder PSK-31 Waterfall Spectrum display on Student’s workstation

20. KPC-3+ Telemetry System

21. KPC-3+ Telemetry System Solar Panel Lab Used for Data Logging

22. Satellite Power Systems Solar Panel IV curve Series/Shunt Regulators NiCd Charge/Discharge

23. Attitude Control Labs Thruster Firing

24. Passive Magnetic Stabilization

25. MagneTorquing Stabilization

26. Momentum Wheel Stabilization

27. Serial Data Telemetry

28. APRS Global Network This data is LIVE Google for “USNA Buoy” Select USNA-1 Google WB4APR-9

29. Our Satellites provide a low cost educational transponder supporting not only GPS position reporting but also remote WX stations and other data link experiments and other University and School Experiments. • The comm channels can potentially draw from over 30,000 experimenters for easy assessment of loading and scaling issues. • Not only the sensors and users exist, but the global Internet collection and distribution system also exists from PCSAT1 & 2.

30. Antenna Deployment

31. Typical ISS Passes

32. USNA Satellites Bob Bruninga, WB4APR