CINEMA PDR, UCB/SSL 1 August 22, 2008 CINEMA Communications & Ground Systems Manfred Bester

CINEMA PDR, UCB/SSL 2 August 22, 2008 Agenda −Concept of Operations −S-Band Communications −Ground Systems −Flight Software −Future Work

CINEMA PDR, UCB/SSL 3 August 22, 2008 Concept of Operations −Mission Orbit Spin Stabilized Spacecraft Baseline Orbit 650 km Circular at 72° Inclination −Pass Coverage Typically 4 Passes/day with 30 min Access Time Tracking via TLEs Downloaded from USSTRATCOM −Data Recovery Store-and-forward Scheme, Downlink at 1 Mbps Recoverable Science Data Volume 760 Mbits/day −Ground Segment MOC and Ground Station Located at UCB/SSL Look into Using Heritage Control System (ITOS)

CINEMA PDR, UCB/SSL 4 August 22, 2008 CINEMA Ground Track

CINEMA PDR, UCB/SSL 5 August 22, 2008 BGS 3m Eng TLM/CMD MHz BGS 11m Science TLM MHz CINEMA MOC at UCB/SSL Communications Concept

CINEMA PDR, UCB/SSL 6 August 22, 2008 S-Band Communications −Telecom Trades −Transceivers −Flight Antennas −Flight Software −Ground Software −Ground Stations −BGS 11m −BGS 3m −Link Budgets −STDN and WiFi Links −Spectrum Licensing

CINEMA PDR, UCB/SSL 7 August 22, 2008 STDN Telemetry Link Frequency2250 MHz ModulationBPSK Spacecraft Antenna Gain-6.0 dBic Spacecraft EIRP-3.0 dBW Range3000 km Path Loss169.1 dB Polarization and Pointing Losses1.0 dB Ground Station G/T (11-m Dish)26.0 dB/K Data Rate1000 kbps Bandwidth1000 kHz Coding Gain (Reed-Solomon)4.3 dB BER10 -6 Required Eb/No6.2 dB Predicted Eb/No19.6 dB Implementation Loss2.3 dB Link Margin11.1 dB S-Band Link Budgets Link Budgets for STDN and WiFi TLM Links WiFi Telemetry Link Frequency2425 MHz Modulation (Spread Spectrum)8FSK Spacecraft Antenna Gain1.0 dBic Spacecraft EIRP0.0 dBW Range3000 km Path Loss169.8 dB Polarization and Pointing Losses0.5 dB Ground Station G/T (3-m Dish)10.0 dB/K Data Rate86 kbps Bandwidth458.7 kHz Coding Gain (Rate-1/2 Convol.)5.7 dB BER10 -6 Required Eb/No4.2 dB Predicted Eb/No11.7 dB Implementation Loss2.0 dB Link Margin5.5 dB

CINEMA PDR, UCB/SSL 8 August 22, 2008 STDN S-Band Link −Transceiver Options:SpaceQuest, Emhiser −Heritage:CHIPSAT, Various Others −Spectrum Licensing:Need NTIA License −Trades Advantages:Can Use BGS “As Is” High Link Margin Low Risk Disadvantages:Onboard Software Changes Ground Software Changes SpaceQuest TX-2400 Transmitter

CINEMA PDR, UCB/SSL 9 August 22, 2008 WiFi S-Band Link −Transceiver Options:MicroHard −Heritage:GENESAT −Spectrum Licensing:Need Amateur Radio License −Trades Advantages:Reuse Existing Flight Hardware and Software Disadvantages:Need Additional Ground Station Unknown Impact of Local WiFi Interference MicroHard MHX-2440 Transceiver

CINEMA PDR, UCB/SSL 10 August 22, 2008 S-Band Prototype Antennas First Prototype Model −Linear Polarized Patch Antenna Overall Dimensions 70.2 x 70.2 mm 2 −RT/Duroid 6002 Material Ordered Thickness mm, Copper Cladding mm, ε r = 2.94 −Fabricate Antenna at SSL −Test with BGS 11-m Antenna in Far Field

CINEMA PDR, UCB/SSL 11 August 22, 2008 S-Band Flight Antennas Flight Models −Circular Polarized Patches: Need 4 −Typical Gain Pattern: Hemispherical with Taper −Performance Goals See Table Below Patch Antenna Performance Goals Parameterθ = 90°θ = 30°θ = 5° Efficiency> 80% Gain> 7 dBic> 0 dBic> -10 dBic Axial Ratio< 1 dB< 6 dB< 10 dB

CINEMA PDR, UCB/SSL 12 August 22, 2008 Ground Systems −Mission Operations −Command and Control System −Mission Planning Products −Ground Station −Science Data Processing

CINEMA PDR, UCB/SSL 13 August 22, 2008 Flight Software Functions TasksFunctions Command ProcessingReal-time Commands, Execution of Stored Table Commands Telemetry DownlinkInterleaving of Real-time and Playback Data Instrument ControlDeployments, High Voltages, Other Parameters Attitude ControlACS Modes Power ControlMonitoring of Power Subsystem, Control Switched Services Thermal ControlMonitor Temperatures Engineering Data RecordingRead-out and Record Sensor Data and Software Parameters Science Data AcquisitionRead-out and Store Science Data Memory ManagementManage Flash Memory Flight Software Functions

CINEMA PDR, UCB/SSL 14 August 22, 2008 Future Work −Communications Design Trades for Selection of Radios Ongoing S-Band Antenna Prototyping Ongoing −Ground Systems Ground Station Options Tied to Selection of Radios Command & Control Systems −Flight Software Received PharmaSat Code from ARC Need to Look into Modifying Code Develop Code to Interface to High-rate Transmitter Consider Other Options Look into CCSDS Compatibility