Systems Simulation Engineer (Constellation Modeling & System Simulation)

About Elveo Elveo is what happens when two pioneers in direct-to-device (D2D) communications join forces. Elveo brings together a combined 20 years of expertise to close the coverage gap for more than 50 mobile network operators (MNOs) and major distribution partners operating in 60+ countries worldwide. That heritage and our technology powers what we call ‘elevated intelligence’ — a new approach that processes and adapts on orbit, delivering voice and data services straight to mobile users, IoT devices and machines across enterprise, government and humanitarian sectors worldwide. As a team, we’re on a mission to deliver powerful compute and connectivity directly to individuals and objects everywhere on Earth. Join us, and become part of a globally inclusive company that is transforming satellite communications from a niche service to an essential global infrastructure, and democratizing connectivity for billions worldwide. Ready to take the next step? Join us.   About the Role Elveo Mobile is building a global direct-to-device satellite constellation. We're looking for a Systems Simulation Engineer to join the team responsible for our core constellation simulation tool — the software that models orbital dynamics, link performance, and system-level behavior for our satellite network. The tool will also form the foundation for the operational System Resource Manager. You'll work alongside the current subject-matter experts to learn and extend the codebase, with the expectation that you'll grow into a primary role as the tool's capabilities expand alongside the constellation program. This is not a pure software role or a pure aerospace system engineering role — it sits at the intersection. What You'll Do - Contribute to the maintenance and extension of the constellation system simulation tool (Python/Rust hybrid architecture), working alongside the current team to keep it a reliable source of truth for mission and systems engineering decisions - Grow into a primary ownership role over time as you build depth on the codebase and the tool's capabilities are expanded to support an evolving constellation program - Implement and validate orbital mechanics models (Walker Delta constellation geometry, J2 perturbation effects, RAAN drift, propagation) and cross-check against STK/HPOP where applicable - Model and validate RF link budgets, antenna gain patterns, SINR/EIRP calculations, and beam/cell assignment logic for the satellite payload - Design and implement performance-critical simulation components in Rust, with Python front-ends/bindings for analysis and integration workflows - Support architecture trade studies (constellation configuration, coverage, capacity) by extending simulation capability to answer new engineering questions on demand - Build tooling and interfaces (APIs, CLI, or lightweight UI) that let other engineers — RF, ADCS, mission ops — run and interpret simulations without needing to touch the core codebase - Help document code, data models, and assumptions as you learn the tool, building institutional knowledge that supports the team's long-term ownership of the codebase - Contribute to system architecture and systems engineering activities beyond the simulation tool itself — supporting trade studies, requirements analysis, and technical decision-making for the constellation program - Participate in the development of the system resource manager, with responsibility for modeling and managing satellite power allocation, frequency assignment, Earth Fixed Cell (EFC) laydown, EFC-to-satellite assignment, and capacity planning - Collaborate directly with mission engineering, RF/payload, and launch teams to translate real system requirements into simulation features - Optimize for performance and scalability as constellation size and simulation complexity grow Required Qualifications - 2-5 years of professional software engineering experience, with strong proficiency in Python and Rust - Demonstrated experience building or maintaining simulation, modeling, or numerical computing tools (scientific computing, physics engines, or similar) - Solid working knowledge of orbital mechanics — Keplerian elements, perturbation effects (J2), constellation geometry (Walker Delta or similar), and propagation methods - Familiarity with satellite systems fundamentals: link budgets, antenna gain/beamforming basics, SINR/EIRP, and RF link performance drivers - Experience with performance profiling and optimization in Rust (memory management, concurrency, FFI/Python bindings via PyO3 or similar) - Strong software engineering fundamentals: version control, testing, CI/CD, and writing maintainable, well-documented code - Ability to ramp quickly on a complex, evolving codebase and take on increasing ownership over time Preferred Qualifications - Experience with STK or other orbital simulation/propagation tools - Knowledge of satellite communications systems (NTN, LTE/5G, TT&C/ground antenna systems, beam hopping, Earth Fixed Cell assignment, or similar) - Experience with graph-based or ML-driven optimization approaches (e.g., auction-based resource allocation, ...) applied to satellite resource management, spectrum/frequency assignment, or beam/cell assignment problems - Exposure to constellation deployment planning or mission operations - Experience working in a small/fast-moving space program environment ITAR Requirements To comply with U.S. Government export control regulations (ITAR), applicants must be one of the following: (i) a U.S. citizen or national, (ii) a lawful permanent resident (green card holder), (iii) a refugee under 8 U.S.C. § 1157, or (iv) an asylee under 8 U.S.C. § 1158. Individuals who do not meet these criteria must be eligible to obtain the necessary authorizations from the U.S. Department of State. Learn about ITAR here: https://www.pmddtc.state.gov Job Location Chantilly, VA