Optimizing Radiation Test Fluence Requirements via Inverse Reliability Analysis: A Mission-Specific Approach

Standard radiation hardness assurance methodologies typically rely on generic, static test fluences (10^7 ions/cm^2) to screen for Destructive Single Event Effects (DSEE). While robust, this “one-size-fits-all” approach often results in costly over-testing. This paper proposes a paradigm shift in test planning, moving from directive-based compliance to a logical, mission-specific derivation of requirements. We present an analytical methodology and tool that demystifies test fluences by deriving them directly from top-level mission reliability and survivability goals. By combining inverse Poisson analysis with orbital event rate calculations, we determine the maximum permissible device cross-section limit for a specific orbit and duration. We then demonstrate how to translate this physical limit into a targeted test fluence that statistically guarantees mission survivability with a specified confidence level. This mathematically traceable path allows engineers to treat test fluence as a dynamic variable, often significantly reducing beam time planning requirements compared to standard directives. This approach is particularly valuable for the initial screening of COTS technologies, expanding the exploration space for candidate parts by validating them against the specific realities of their intended mission rather than generic standards.