In-Orbit Test of A Satellite Communication Payload

1. In-Orbit Test of A Satellite Communication Payload Albert Lin, (310) 416-3648, albert.y.lin@boeing.com Shawn Struc, (310) 335-6335, shawn.m.struc@boeing.com Toni Spiteri, (310) 662-9576, toni.m.spiteri@boeing.com Boeing Space & Intelligence Systems El Segundo, CA

2. Communication Payload In-Orbit (PIOT) Test Objectives … • Verify payload and antenna subsystem health post launch • Tests are conducted in the on-station configuration to ensure payload hardware has not been degraded by exposure to launch, transfer orbit, deployments, and on-station environments • Trend PIOT measurements using factory system test as a baseline in either a pre-coordinated test longitude or spacecraft operational longitude • Perform on-orbit antenna far-field measurements to validate coverage performance and alignment, by comparing with factory test near field or modeled pattern data • Measure and validate phased array calibration baseline (satellite-dependent) • Prepare for handover to customer or End-To-End system validation

3. Mission Description … • Payload Initialization • Antenna Phased Array / Beacon Calibration • Antenna Mapping • Repeater and Telemetry and Command Test • Antenna Alignment Adjustment • Handover Configuration

4. Payload Architecture Scope • Analog “Bentpipe” Repeater Payloads • BSS/FSS repeaters • Spot beam repeaters • Digital Communication Payloads • Geo-mobile satellites • On-board digital processing and packet switching • Phased array antenna • Satellite Telemetry and Command RF subsystem • Command receivers and telemetry transmitters

5. Typical Communication PIOT Setup

6. PIOT Flow/Life Cycle

7. Test Design • Payload Configuration • Antenna Mapping • Communication Payload Tests • Array Calibration

8. Payload Configuration • Purpose • Command payload units on and confirm appropriate telemetry responses • Approach • Configure to trend factory data • Redundant • Demonstrate health of redundant hardware not used in nominal on-station configuration • Redundant testing performed prior to primary testing to minimize power cycling of units • Primary • Demonstrate performance of primary operational hardware prior to handover • Final Handover • Final configuration required for transition to next test phase or customer operation

9. Antenna Mapping • Purpose • Demonstrate functional integrity • Beam forming capability (for payload with array antenna) • Determine antenna subsystem alignments via spacecraft slews and RF measurements • Adjust antenna alignment if necessary • Approach • Slewing spacecraft • Measure at different spots on the ground • Beam Selection • Broad/Global Beam • Cut Example • Spot Beam • Cut Example

10. Typical Communication PIOT Tests • Purpose • Demonstrate health of all payload units via RF measurements • Approach • Use standard test types as factory to characterize performance for data trending • Passband flatness • Effective Isotopic Radiated power (EIRP) • Power control • Build in flexibilities and limitations into test flow • Account for environment such as weather and unexpected outside factors

11. Phased Array Calibration • Purpose • Iterative optimization demonstrates calibrated phased array antenna is within specified performance residual accuracy in phase and amplitude • Approach • Array calibration is performed and demonstrated on the ground during factory testing, but residual near-field testing errors remain • Diurnal testing performed during PIOT to confirm antenna performance stability over a 24-hour period

12. PIOT Preparation • Site Survey • Ground Antenna System Interface • Field of View Blockage • Frequency allocation/coordination • Antenna Hub Interface • RF and mechanical interface • Installation Considerations • Building permit for remote installation • IOT equipment location and cable routing • Ground Station Characterization • Instrument calibrations required for absolute power measurements • Verify ground station has sufficient measurement capability • Ground station performance on G/T, EIRP, uplink and downlink dynamic range, passband response

13. PIOT Preparation (cont) • Test hardware and software • Equipment can be assembled and verified prior to deploying to PIOT ground station to reduce test setup issues • Rehearsal • Payload commanding scripts and IOT procedures • Training • Coordination with other spacecraft subsystems required • Risk Mitigation Tests • Subsystem tests • Stand-alone test equipment • Network and communication links • Software simulations • Ground testing against spacecraft in factory

14. PIOT Logistics • Logistic Operation /Customer Interactions • Provide sufficient workspace • PIOT team requires adequate location for test measurements and analysis • Presentation space required for customer data reviews • Team Communication Plan • Schedule Flexibility • Dynamic schedule changes to accommodate customer needs and other mission subsystems as well as unexpected events such as weather • Alternative tests can be identified as a backup plan

15. Conclusion … • Payload IOT process has been proven over 17 years • Continue to improve and evolve for more complex payloads and to maintain high performance standard Preparation and rehearsal are the keys to success!