Principal RF Engineer at AST SpaceMobile in Dallas, TX

Job description

AST SpaceMobile and our global partners are building the first and only space-based cellular broadband network to be accessible by standard smartphones. Called SpaceMobile, this ultra-powerful network is being designed to provide connectivity at 4G/5G speeds everywhere on the planet – on land, at sea and in flight. Position Overview We are seeking a Principal RF Engineer to support the design, analysis, and optimization of advanced satellite-based communications systems. This role is responsible for developing RF performance models, link budgets, and coverage analyses to evaluate end-to-end network performance across space and ground segments. The Principal RF Engineer will work closely with cross-functional engineering teams to assess system performance, optimize network availability, and support the development of reliable, high-capacity communications solutions. Key Responsibilities Develop, maintain, and analyze uplink and downlink link budgets, including EIRP, G/T, path loss, atmospheric effects, antenna performance, fade margins, and system availability. Create RF performance models to evaluate end-to-end communications performance under various operational and environmental conditions. Analyze phased array antenna performance, including beamforming, scan loss, sidelobe behavior, coverage patterns, and beam isolation. Evaluate the effects of Doppler shifts, propagation delays, latency, and user device constraints on network performance and capacity. Collaborate with network, systems, and radio engineering teams to assess modulation, coding schemes, throughput, and overall service performance. Develop and maintain feeder link analyses using industry-standard propagation models to evaluate weather impacts and network availability. Assess and optimize fade mitigation techniques such as adaptive coding and modulation (ACM), power control strategies, and diversity solutions. Perform system availability, sensitivity, and trade-off analyses to support infrastructure planning and performance optimization. Analyze RF hardware impairments, including interference, phase noise, amplifier non-linearity, and other factors affecting system performance. Develop simulations, analytical tools, dashboards, and reports to support engineering studies and operational assessments. Establish performance requirements, validate design assumptions, and support verification activities throughout the development lifecycle. Support troubleshooting efforts by developing performance baselines and assisting in root cause investigations. Provide technical leadership and guidance on RF system analysis, architecture trade studies, and engineering best practices. Qualifications Education Bachelor’s degree in Electrical Engineering, Telecommunications Engineering, Aerospace Engineering, Physics, or a related technical field. Master’s degree in a relevant engineering discipline preferred. Relevant industry certifications or specialized training in RF engineering, wireless communications, or satellite communications are a plus. Experience Minimum 5 years of experience in RF systems engineering, satellite communications, wireless communications, or communications link analysis. Experience developing and maintaining communication system link budgets and RF performance models. Experience working with complex RF systems and multi-segment communications architectures. Demonstrated experience leading technical analyses, trade studies, and cross-functional engineering initiatives. Experience supporting communications infrastructure deployment, optimization, or operational performance assessments. Preferred Qualifications Experience with satellite communications, non-terrestrial networks (NTN), or advanced wireless communication systems. Familiarity with atmospheric propagation modeling and communications availability analysis methodologies. Knowledge of adaptive coding and modulation, power control systems, and diversity techniques. Experience with phased array anten