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The dielectric surfaces of a spacecraft exposed to the Earth's magnetospheric plasma and trapped electron environment build up differential voltages which can result in electrostatic discharges in surface materials. These discharges result in transient ground currents and radiated electromagnetic energy which can degrade the function of electronics units and thermal control surfaces. In addition, the Earth's trapped electron and proton radiation environment causes optical and mechanical damage to surface materials and degradation of active semiconductor device performance. This paper describes an approach to reducing the hazards of these phenomena by discussing the radiation hardness design of a specific communications satellite. The methods used to identify design weak points, test materials, and develop new materials are described. Specific implemented materials and design practices which have reduced the susceptibility of the spacecraft to surface charging and radiation damage effects are noted.

Trends in RF performance requirements for contemporary spacecraft are driving vehicle design to achieve extremely low RF emissions levels due to unintentional sources. This paper describes an approach to achieving very low spurious RF emissions in spacecraft by identifying, predicting and controlling emissions sources during architecture development. The approach incorporates detailed, tailored analysis and test methods used to verify performance compliance. Specific test results are discussed in the context of showing the effectiveness of this design approach in meeting tailored MIL-STD-461E radiated emissions limits.

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Designing the Dragon COTS (Commercial Orbital Transfer System) for EMI/EMC interface compliance to the International Space Station (ISS) is a complex task. It involves designing Dragon for self-compatibility, compatibility with the Falcon 9 Launch Vehicle, designing to the LEO Space radiation environment, as well as interface compatibility to the ISS mechanical, electrical and RF interfaces. This paper describes the Space Exploration Technologies tailored approach to achieve Dragon spacecraft self-compatibility, compatibility with the Eastern Launch Range RF requirements and interface compatibility to SSP 30237, 30238 and 30243, respectively, the ISS requirements for EMC emissions and susceptibility, and test methods for verification and overall ISS EMC compatibility. The detailed design analysis methods used to predict design performance are described, as well as the detailed tailored test methods used to verify functional performance and margins to the Falcon 9 LV, Eastern Launch Range RF requirements, and the ISS suite of EMC and survivability requirements.