Principal Engineer - RAN (Satellite to Cellular Networks)

Job Description

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.

Summary:

Act as the end-to-end technical authority for the Radio Access Network within AST's Satellite & Cellular Networks Integration (SCNI) program. This role blends system-level architecture, Layer 1–3 troubleshooting, and deep RF protocol expertise. You'll lead validation from lab to field, drive performance alignment with Tier 1 operators and other global operators and ensure the radio interface is launch-ready for AST's direct-to-device satellite service.

This role serves as the face of AST for all RAN-related matters—acting as the E2E technical authority across internal teams and external stakeholders, both local and international.

Key Responsibilities:

• Architect and own RAN subsystem integration across satellite and terrestrial interfaces
• Drive simulations, E2E scenario design, vendor interoperability, and benchmark testing
• Execute RF analysis, cell parameter tuning, and interference resolution for multi-vendor RAN
• Lead deep-dive debugging across Layer 1 (PHY), Layer 2 (MAC/RLC), and Layer 3 (RRC/S1AP)
• Perform log-level analysis using UE tools (QXDM, TEMS, Accuver) and network-side logs
• Validate handovers, paging, call flows, and KPIs across satellite beam and terrestrial boundaries
• Collaborate with device OEMs, gateway teams, and satellite payload SMEs to align RF interface
• Contribute to lab setup, coverage modeling, and automation of testing pipelines

Preferred Background:

• 15–20+ years of telecom experience with deep technical ownership in RAN, RF, and Layer 3 protocols
• VoLTE and VoNR expert with hands-on optimization across NTN to TN (Satellite to Cellular) call flows as per 3GPP Release 17/18
• The RAN Principal Engineer must have deep expertise across LTE, 5G NR, VoLTE, and VoNR features, with hands-on experience in performance analysis using tools such as QXDM, Actix, and TEMS— owning the validation cycle end-to-end through to production-grade acceptance. Must be able to lead deep-dive debugging across Layer 1 (PHY), Layer 2 (MAC/RLC), and Layer 3 (RRC/S1AP).
• Proven delivery in Tier-1 operator environments
• Strong expertise in physical layer design, Layer 3 decoding, and protocol-level troubleshooting
• Experience with 5G SA/NSA, cloud-native architectures, and satellite NTN adaptations
• Hands-on with tools: TEMS, QXDM, Accuver, Keysight, Spirent, Anritsu, Wireshark
• Vendor management experience

Notable Achievements:

• Led commercial rollouts or lab-to-field transitions in Tier-1 networks
• Developed architecture or troubleshooting frameworks adopted across OEMs
• Filed patents or delivered innovative solutions in RF or Layer 3 domains

Soft Skills:

• High accountability and execution under pressure
• Cross-functional influence without formal authority
• Exceptional documentation, system modeling, and executive communication skills
• Independent and result-driven, able to deliver without direct supervision

AST SpaceMobile is an Equal Opportunity, at will Employer; employment is governed on the basis of merit, competence and qualifications and will not be influenced in any manner by race, color, religion, gender, national origin/ethnicity, veteran status, disability status, age, sexual orientation, gender identity, marital status, mental or physical disability or any other legally protected status.